* [PATCH V2 1/2] Bound violation handling preparation. @ 2015-12-18 13:44 Walfred Tedeschi 2015-12-18 13:44 ` [PATCH V2 2/2] Bound violation handling Walfred Tedeschi 0 siblings, 1 reply; 4+ messages in thread From: Walfred Tedeschi @ 2015-12-18 13:44 UTC (permalink / raw) To: palves, brobecker; +Cc: gdb-patches, Walfred Tedeschi In the place notifier was the inferior is still not stopped. Moved the observer to where the inferior is already signaled as stopped and evaluation can be done. 2015-12-15 Walfred Tedeschi <walfred.tedeschi@intel.com> * infrun.c (normal_stop): Change observers placement within the function. --- gdb/infrun.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/gdb/infrun.c b/gdb/infrun.c index f9bb411..2ed807c 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -8174,9 +8174,6 @@ normal_stop (void) instead of after. */ update_thread_list (); - if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal) - observer_notify_signal_received (inferior_thread ()->suspend.stop_signal); - /* As with the notification of thread events, we want to delay notifying the user that we've switched thread context until the inferior actually stops. @@ -8282,6 +8279,9 @@ normal_stop (void) do_cleanups (old_chain); } + if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal) + observer_notify_signal_received (inferior_thread ()->suspend.stop_signal); + /* Notify observers about the stop. This is where the interpreters print the stop event. */ if (!ptid_equal (inferior_ptid, null_ptid)) -- 2.1.4 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH V2 2/2] Bound violation handling. 2015-12-18 13:44 [PATCH V2 1/2] Bound violation handling preparation Walfred Tedeschi @ 2015-12-18 13:44 ` Walfred Tedeschi 0 siblings, 0 replies; 4+ messages in thread From: Walfred Tedeschi @ 2015-12-18 13:44 UTC (permalink / raw) To: palves, brobecker; +Cc: gdb-patches, Walfred Tedeschi With Intel Memory Protection Extensions it was introduced the concept of boundary violation. A boundary violations is presented to the inferior as a segmentation fault having as sigcode the value 3. This patch adds a handler for a boundary violation extending the information displayed when a bound violation is presented to the inferior. In the stop mode case the debugger will also display the kind of violation: "upper" or "lower", bounds and the address accessed. On no stop mode the information will still remain unchanged. Additional information about bound violations are not meaningful in that case user does not know the line in which violation occurred as well. When the segmentation fault handler is stop mode the out puts will be changed as exemplified below. The usual output of a segfault is: Program received signal SIGSEGV, Segmentation fault 0x0000000000400d7c in upper (p=0x603010, a=0x603030, b=0x603050, c=0x603070, d=0x603090, len=7) at i386-mpx-sigsegv.c:68 68 value = *(p + len); In case it is a bound violation it will be presented as: Program received signal SIGSEGV, Segmentation fault upper bound violation - bounds {lbound = 0x603010, ubound = 0x603023} accessing 0x60302f. 0x0000000000400d7c in upper (p=0x603010, a=0x603030, b=0x603050, c=0x603070, d=0x603090, len=7) at i386-mpx-sigsegv.c:68 68 value = *(p + len); In mi mode the output of a segfault is: *stopped,reason="signal-received",signal-name="SIGSEGV", signal-meaning="Segmentation fault", frame={addr="0x0000000000400d7c", func="upper",args=[{name="p", value="0x603010"},{name="a",value="0x603030"} ,{name="b",value="0x603050"}, {name="c",value="0x603070"}, {name="d",value="0x603090"},{name="len",value="7"}], file="i386-mpx-sigsegv.c",fullname="i386-mpx-sigsegv.c",line="68"}, thread-id="1",stopped-threads="all",core="6" in the case of a bound violation: *stopped,reason="signal-received",signal-name="SIGSEGV", signal-meaning="Segmentation fault", sigcode-meaning="upper bound violation", lower-bound="0x603010",upper-bound="0x603023",bound-access="0x60302f", frame={addr="0x0000000000400d7c",func="upper",args=[{name="p", value="0x603010"},{name="a",value="0x603030"},{name="b",value="0x603050"}, {name="c",value="0x603070"},{name="d",value="0x603090"}, {name="len",value="7"}],file="i386-mpx-sigsegv.c", fullname="i386-mpx-sigsegv.c",line="68"},thread-id="1", stopped-threads="all",core="6" Changelog: 2015-12-15 Walfred Tedeschi <walfred.tedeschi@intel.com> * amd64-linux-tdep.c (amd64_linux_init_abi_common): Add handler for bound violation. * gdbarch.sh (bound_violation_handler): New. * gdbarch.c: Regenerate. * gdbarch.h: Regenerate. * i386-linux-tdep.c (i386_mpx_bound_violation_handler): New. (i386_linux_init_abi): Use i386_mpx_bound_violation_handler. * i386-linux-tdep.h (i386_mpx_bound_violation_handler) New. * i386-tdep.c (i386_mpx_enabled): Add as external. * i386-tdep.c (i386_mpx_enabled): Add as external. * infrun.c (handle_segmentation_faults): New function. (print_signal_received_reason): Use handle_segmentation_faults. (normal_stop): Change order of observer in order to have the inferior stopped for evaluation. testsuite/gdb.arch * i386-mpx-sigsegv.c: New. * i386-mpx-sigsegv.exp: New. * i386-mpx-simple_segv.c: New. * i386-mpx-simple_segv.exp: New. --- gdb/amd64-linux-tdep.c | 3 + gdb/gdbarch.c | 32 ++++++ gdb/gdbarch.h | 11 ++ gdb/gdbarch.sh | 6 ++ gdb/i386-linux-tdep.c | 46 +++++++++ gdb/i386-linux-tdep.h | 5 + gdb/i386-tdep.c | 4 +- gdb/i386-tdep.h | 2 + gdb/infrun.c | 34 +++++++ gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c | 120 ++++++++++++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp | 86 ++++++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c | 66 ++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp | 129 ++++++++++++++++++++++++ 13 files changed, 541 insertions(+), 3 deletions(-) create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c index bde751f..954855b 100644 --- a/gdb/amd64-linux-tdep.c +++ b/gdb/amd64-linux-tdep.c @@ -1840,6 +1840,9 @@ amd64_linux_init_abi_common(struct gdbarch_info info, struct gdbarch *gdbarch) set_gdbarch_process_record_signal (gdbarch, amd64_linux_record_signal); set_gdbarch_get_siginfo_type (gdbarch, x86_get_siginfo_type_with_fields); + set_gdbarch_bound_violation_handler(gdbarch, + i386_mpx_bound_violation_handler); + } static void diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c index f04eef9..42eb4db 100644 --- a/gdb/gdbarch.c +++ b/gdb/gdbarch.c @@ -189,6 +189,7 @@ struct gdbarch int num_pseudo_regs; gdbarch_ax_pseudo_register_collect_ftype *ax_pseudo_register_collect; gdbarch_ax_pseudo_register_push_stack_ftype *ax_pseudo_register_push_stack; + gdbarch_bound_violation_handler_ftype *bound_violation_handler; int sp_regnum; int pc_regnum; int ps_regnum; @@ -531,6 +532,7 @@ verify_gdbarch (struct gdbarch *gdbarch) /* Skip verify of num_pseudo_regs, invalid_p == 0 */ /* Skip verify of ax_pseudo_register_collect, has predicate. */ /* Skip verify of ax_pseudo_register_push_stack, has predicate. */ + /* Skip verify of bound_violation_handler, has predicate. */ /* Skip verify of sp_regnum, invalid_p == 0 */ /* Skip verify of pc_regnum, invalid_p == 0 */ /* Skip verify of ps_regnum, invalid_p == 0 */ @@ -773,6 +775,12 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file) "gdbarch_dump: bits_big_endian = %s\n", plongest (gdbarch->bits_big_endian)); fprintf_unfiltered (file, + "gdbarch_dump: gdbarch_bound_violation_handler_p() = %d\n", + gdbarch_bound_violation_handler_p (gdbarch)); + fprintf_unfiltered (file, + "gdbarch_dump: bound_violation_handler = <%s>\n", + host_address_to_string (gdbarch->bound_violation_handler)); + fprintf_unfiltered (file, "gdbarch_dump: breakpoint_from_pc = <%s>\n", host_address_to_string (gdbarch->breakpoint_from_pc)); fprintf_unfiltered (file, @@ -1986,6 +1994,30 @@ set_gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, } int +gdbarch_bound_violation_handler_p (struct gdbarch *gdbarch) +{ + gdb_assert (gdbarch != NULL); + return gdbarch->bound_violation_handler != NULL; +} + +void +gdbarch_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out *uiout) +{ + gdb_assert (gdbarch != NULL); + gdb_assert (gdbarch->bound_violation_handler != NULL); + if (gdbarch_debug >= 2) + fprintf_unfiltered (gdb_stdlog, "gdbarch_bound_violation_handler called\n"); + gdbarch->bound_violation_handler (gdbarch, uiout); +} + +void +set_gdbarch_bound_violation_handler (struct gdbarch *gdbarch, + gdbarch_bound_violation_handler_ftype bound_violation_handler) +{ + gdbarch->bound_violation_handler = bound_violation_handler; +} + +int gdbarch_sp_regnum (struct gdbarch *gdbarch) { gdb_assert (gdbarch != NULL); diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h index b9b2290..f1436d8 100644 --- a/gdb/gdbarch.h +++ b/gdb/gdbarch.h @@ -63,6 +63,7 @@ struct ravenscar_arch_ops; struct elf_internal_linux_prpsinfo; struct mem_range; struct syscalls_info; +struct ui_out; #include "regcache.h" @@ -299,6 +300,16 @@ typedef int (gdbarch_ax_pseudo_register_push_stack_ftype) (struct gdbarch *gdbar extern int gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, struct agent_expr *ax, int reg); extern void set_gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, gdbarch_ax_pseudo_register_push_stack_ftype *ax_pseudo_register_push_stack); +/* Function called when a segmentation fault signal is received by the inferior, + having sigcode = 3 (SIG_CODE_BOUNDARY_FAULT). + UIOUT is the output stream where the handler will place information. */ + +extern int gdbarch_bound_violation_handler_p (struct gdbarch *gdbarch); + +typedef void (gdbarch_bound_violation_handler_ftype) (struct gdbarch *gdbarch, struct ui_out *uiout); +extern void gdbarch_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out *uiout); +extern void set_gdbarch_bound_violation_handler (struct gdbarch *gdbarch, gdbarch_bound_violation_handler_ftype *bound_violation_handler); + /* GDB's standard (or well known) register numbers. These can map onto a real register or a pseudo (computed) register or not be defined at all (-1). diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh index 236ce41..f36f0e0 100755 --- a/gdb/gdbarch.sh +++ b/gdb/gdbarch.sh @@ -446,6 +446,11 @@ M:int:ax_pseudo_register_collect:struct agent_expr *ax, int reg:ax, reg # Return -1 if something goes wrong, 0 otherwise. M:int:ax_pseudo_register_push_stack:struct agent_expr *ax, int reg:ax, reg +# Function called when a segmentation fault signal is received by the inferior, +# having sigcode = 3 (SIG_CODE_BOUNDARY_FAULT). +# UIOUT is the output stream where the handler will place information. +M:void:bound_violation_handler:struct ui_out *uiout:uiout + # GDB's standard (or well known) register numbers. These can map onto # a real register or a pseudo (computed) register or not be defined at # all (-1). @@ -1247,6 +1252,7 @@ struct ravenscar_arch_ops; struct elf_internal_linux_prpsinfo; struct mem_range; struct syscalls_info; +struct ui_out; #include "regcache.h" diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c index 766f193..998f38c 100644 --- a/gdb/i386-linux-tdep.c +++ b/gdb/i386-linux-tdep.c @@ -30,6 +30,7 @@ #include "i386-tdep.h" #include "i386-linux-tdep.h" #include "linux-tdep.h" +#include "utils.h" #include "glibc-tdep.h" #include "solib-svr4.h" #include "symtab.h" @@ -384,6 +385,48 @@ i386_canonicalize_syscall (int syscall) return gdb_sys_no_syscall; } +void +i386_mpx_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out *uiout) +{ + CORE_ADDR lower_bound, upper_bound, access; + int is_upper; + + if (!i386_mpx_enabled ()) + return; + TRY + { + lower_bound + = parse_and_eval_long ("$_siginfo._sifields._sigfault._addr_bnd._lower"); + upper_bound + = parse_and_eval_long ("$_siginfo._sifields._sigfault._addr_bnd._upper"); + access + = parse_and_eval_long ("$_siginfo._sifields._sigfault.si_addr"); + } + CATCH (exception, RETURN_MASK_ALL) + { + return; + } + END_CATCH + + is_upper = (access > upper_bound ? 1 : 0); + + ui_out_text (uiout, "\n"); + if (is_upper) + ui_out_field_string (uiout, "sigcode-meaning", "upper bound violation"); + else + ui_out_field_string (uiout, "sigcode-meaning", "lower bound violation"); + + ui_out_text (uiout, " - bounds {lbound = "); + ui_out_field_fmt (uiout,"lower-bound", "%s", paddress (gdbarch, lower_bound)); + ui_out_text (uiout, ", ubound = "); + ui_out_field_fmt (uiout,"upper-bound", "%s", paddress (gdbarch, upper_bound)); + ui_out_text (uiout, "}"); + ui_out_text (uiout, " accessing "); + ui_out_field_fmt (uiout,"bound-access", "%s", paddress (gdbarch, access)); + + return; +} + /* Parse the arguments of current system call instruction and record the values of the registers and memory that will be changed into "record_arch_list". This instruction is "int 0x80" (Linux @@ -1002,6 +1045,9 @@ i386_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) i386_linux_get_syscall_number); set_gdbarch_get_siginfo_type (gdbarch, x86_get_siginfo_type_with_fields); + set_gdbarch_bound_violation_handler(gdbarch, + i386_mpx_bound_violation_handler); + } /* Provide a prototype to silence -Wmissing-prototypes. */ diff --git a/gdb/i386-linux-tdep.h b/gdb/i386-linux-tdep.h index f42bf7a..78efa76 100644 --- a/gdb/i386-linux-tdep.h +++ b/gdb/i386-linux-tdep.h @@ -37,6 +37,11 @@ /* Get XSAVE extended state xcr0 from core dump. */ extern uint64_t i386_linux_core_read_xcr0 (bfd *abfd); +/* Handles and displays information related to the MPX bound violation + to the user. */ +void +i386_mpx_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out *uiout); + /* Linux target description. */ extern struct target_desc *tdesc_i386_linux; extern struct target_desc *tdesc_i386_mmx_linux; diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c index ebb21fc..60be128 100644 --- a/gdb/i386-tdep.c +++ b/gdb/i386-tdep.c @@ -8651,9 +8651,7 @@ i386_mpx_bd_base (void) return ret & MPX_BASE_MASK; } -/* Check if the current target is MPX enabled. */ - -static int +int i386_mpx_enabled (void) { const struct gdbarch_tdep *tdep = gdbarch_tdep (get_current_arch ()); diff --git a/gdb/i386-tdep.h b/gdb/i386-tdep.h index 95288ba..cd272b3 100644 --- a/gdb/i386-tdep.h +++ b/gdb/i386-tdep.h @@ -420,6 +420,8 @@ extern int i386_process_record (struct gdbarch *gdbarch, struct regcache *regcache, CORE_ADDR addr); extern const struct target_desc *i386_target_description (uint64_t xcr0); +/* Verify if target is MPX enabled. */ +extern int i386_mpx_enabled (void); \f /* Functions and variables exported from i386bsd-tdep.c. */ diff --git a/gdb/infrun.c b/gdb/infrun.c index 2ed807c..8c80303 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -7893,6 +7893,36 @@ print_exited_reason (struct ui_out *uiout, int exitstatus) } } +/* Value of the sigcode in case of a boundary fault. */ + +#define SIG_CODE_BONDARY_FAULT 3 + +/* Verifies if a received segmentation fault is a boundary fault. + In the case it is it calls the architecture dependent function + to handle the boundary fault. */ + +static void +handle_segmentation_faults (struct ui_out *uiout) +{ + long sig_code = 0; + struct regcache *regcache = get_current_regcache (); + struct gdbarch *gdbarch = get_regcache_arch (regcache); + + TRY + { + sig_code = parse_and_eval_long ("$_siginfo.si_code\n"); + } + CATCH (exception, RETURN_MASK_ALL) + { + return; + } + END_CATCH + + if (sig_code == SIG_CODE_BONDARY_FAULT + && gdbarch_bound_violation_handler_p (gdbarch)) + gdbarch_bound_violation_handler (gdbarch, uiout); +} + void print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal) { @@ -7922,6 +7952,10 @@ print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal) annotate_signal_string (); ui_out_field_string (uiout, "signal-meaning", gdb_signal_to_string (siggnal)); + + if (siggnal == GDB_SIGNAL_SEGV) + handle_segmentation_faults (uiout); + annotate_signal_string_end (); } ui_out_text (uiout, ".\n"); diff --git a/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c new file mode 100644 index 0000000..7500352 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c @@ -0,0 +1,120 @@ +/* Copyright (C) 2015 Free Software Foundation, Inc. + + Contributed by Intel Corp. <walfred.tedeschi@intel.com> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "x86-cpuid.h" +#include <stdio.h> + +#define OUR_SIZE 5 + +int gx[OUR_SIZE]; +int ga[OUR_SIZE]; +int gb[OUR_SIZE]; +int gc[OUR_SIZE]; +int gd[OUR_SIZE]; + +unsigned int +have_mpx (void) +{ + unsigned int eax, ebx, ecx, edx; + + if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx)) + return 0; + + if ((ecx & bit_OSXSAVE) == bit_OSXSAVE) + { + if (__get_cpuid_max (0, NULL) < 7) + return 0; + + __cpuid_count (7, 0, eax, ebx, ecx, edx); + + if ((ebx & bit_MPX) == bit_MPX) + return 1; + else + return 0; + } + return 0; +} + +int +bp1 (int value) +{ + return 1; +} + +int +bp2 (int value) +{ + return 1; +} + +void +upper (int * p, int * a, int * b, int * c, int * d, int len) +{ + int value; + value = *(p + len); + value = *(a + len); + value = *(b + len); + value = *(c + len); + value = *(d + len); +} + +void +lower (int * p, int * a, int * b, int * c, int * d, int len) +{ + int value; + value = *(p - len); + value = *(a - len); + value = *(b - len); + value = *(c - len); + bp2 (value); + value = *(d - len); +} + +int +main (void) +{ + if (have_mpx ()) + { + int sx[OUR_SIZE]; + int sa[OUR_SIZE]; + int sb[OUR_SIZE]; + int sc[OUR_SIZE]; + int sd[OUR_SIZE]; + int *x, *a, *b, *c, *d; + + x = calloc (OUR_SIZE, sizeof (int)); + a = calloc (OUR_SIZE, sizeof (int)); + b = calloc (OUR_SIZE, sizeof (int)); + c = calloc (OUR_SIZE, sizeof (int)); + d = calloc (OUR_SIZE, sizeof (int)); + + upper (x, a, b, c, d, OUR_SIZE + 2); + upper (sx, sa, sb, sc, sd, OUR_SIZE + 2); + upper (gx, ga, gb, gc, gd, OUR_SIZE + 2); + lower (x, a, b, c, d, 1); + lower (sx, sa, sb, sc, sd, 1); + bp1 (*x); + lower (gx, ga, gb, gc, gd, 1); + + free (x); + free (a); + free (b); + free (c); + free (d); + } + return 0; +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp new file mode 100644 index 0000000..2de6b4a --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp @@ -0,0 +1,86 @@ +# Copyright (C) 2015 Free Software Foundation, Inc. +# +# Contributed by Intel Corp. <walfred.tedeschi@intel.com> +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + + +if { ![istarget i?86-*-*] && ![istarget x86_64-*-* ] } { + verbose "Skipping x86 MPX tests." + return +} + +standard_testfile + +set comp_flags "-mmpx -fcheck-pointer-bounds -I${srcdir}/../nat/" + +if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} \ + [list debug nowarnings additional_flags=${comp_flags}]] } { + return -1 +} + +if ![runto_main] { + untested "could not run to main" + return -1 +} + +gdb_test_multiple "print have_mpx ()" "have mpx" { + -re ".. = 1\r\n$gdb_prompt " { + pass "check whether processor supports MPX" + } + -re ".. = 0\r\n$gdb_prompt " { + verbose "processor does not support MPX; skipping MPX tests" + return + } +} + +set segv_lower_bound ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nlower bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +set segv_upper_bound ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +for {set i 0} {$i < 15} {incr i} { + set message "MPX signal segv Upper: ${i}" + gdb_test_multiple "continue" "$message ${i}" { + -re $segv_upper_bound { + pass "$message" + } + -re ".*$inferior_exited_re normally.*$gdb_prompt $" { + fail "$message" + break + } + } + gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "$message: should be in upper" +} + +for {set i 0} {$i < 15} {incr i} { + set message "MPX signal segv Lower: ${i}" + gdb_test_multiple "continue" "$message ${i}" { + -re $segv_lower_bound { + pass "$message ${i}" + } + -re ".*$inferior_exited_re normally.*$gdb_prompt $" { + fail "$message ${i}" + break + } + } + gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in lower.*"\ + "$message: should be in lower" +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c new file mode 100644 index 0000000..5317369 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c @@ -0,0 +1,66 @@ +/* Copyright (C) 2015 Free Software Foundation, Inc. + + Contributed by Intel Corp. <walfred.tedeschi@intel.com> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "x86-cpuid.h" +#include <stdio.h> + +#define OUR_SIZE 5 + +unsigned int +have_mpx (void) +{ + unsigned int eax, ebx, ecx, edx; + + if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx)) + return 0; + + if ((ecx & bit_OSXSAVE) == bit_OSXSAVE) + { + if (__get_cpuid_max (0, NULL) < 7) + return 0; + + __cpuid_count (7, 0, eax, ebx, ecx, edx); + + if ((ebx & bit_MPX) == bit_MPX) + return 1; + else + return 0; + } + return 0; +} + +void +upper (int * p, int len) +{ + int value; + len++; /* b0-size-test. */ + value = *(p + len); +} + +int +main (void) +{ + if (have_mpx ()) + { + int a = 0; /* Dummy variable for debugging purposes. */ + int sx[OUR_SIZE]; + a++; /* register-eval. */ + upper (sx, OUR_SIZE + 2); + return sx[1]; + } + return 0; +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp new file mode 100644 index 0000000..6b099d6 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp @@ -0,0 +1,129 @@ +# Copyright (C) 2015 Free Software Foundation, Inc. +# +# Contributed by Intel Corp. <walfred.tedeschi@intel.com> +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# Testing handle setup together with boundary violation signals. +# +# Some states are not allowed as reported on the manual, as noprint +# implies nostop, but nostop might print. +# +# Caveat: Setting the handle to nopass, ends up in a endless loop. + +if { ![istarget i?86-*-*] && ![istarget x86_64-*-* ] } { + verbose "Skipping x86 MPX tests." + return +} + +standard_testfile + +set comp_flags "-mmpx -fcheck-pointer-bounds -I${srcdir}/../nat/" + +if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} \ + [list debug nowarnings additional_flags=${comp_flags}]] } { + return -1 +} + +if ![runto_main] { + untested "could not run to main" + return -1 +} + +send_gdb "print have_mpx ()\r" +gdb_expect { + -re ".. = 1\r\n$gdb_prompt " { + pass "check whether processor supports MPX" + } + -re ".. = 0\r\n$gdb_prompt " { + verbose "processor does not support MPX; skipping MPX tests" + return + } +} + +set segv_bound_with_prompt ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +set segv_bound_with_exit ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$inferior_exited_re.*" + +set segv_with_exit ".*Program received signal SIGSEGV,\ + Segmentation fault.*$inferior_exited_re.*" + +# Using the handler for SIGSEGV as "print pass stop" +set parameters "print pass stop" +runto_main +send_gdb "handle SIGSEGV $parameters\n" +send_gdb "continue\n" + +gdb_expect { + -re $segv_bound_with_prompt { + pass $parameters + } +} +gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "should be in upper; $parameters" + +# Using the handler for SIGSEGV as "print pass nostop" +set parameters "print pass nostop" +runto_main + +gdb_test "handle SIGSEGV $parameters" "" "Setting\ +the handler for segfault 0" + +gdb_test_multiple "continue" "test 0" { + -re $segv_with_exit { + pass $parameters + } + -re "$gdb_prompt $" { + fail $parameters + } +} + +gdb_test "where" "No stack." "no inferior $parameters" + +# Using the handler for SIGSEGV as "print nopass stop" +set parameters "print nopass stop" + +runto_main +gdb_test "handle SIGSEGV $parameters" "" "Setting\ +the handler for segfault 1" + +gdb_test_multiple "continue" "test 1" { + -re $segv_bound_with_prompt { + pass $parameters + } +} + +gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "should be in upper $parameters" + +# print nopass stop +set parameters "noprint pass nostop" +runto_main + +gdb_test "handle SIGSEGV $parameters" "" "Setting\ +the handler for segfault 2" + +gdb_test_multiple "continue" "test 2" { + -re "Continuing\..*$inferior_exited_re.*" { + pass $parameters + } +} + +gdb_test "where" "No stack." "no inferior $parameters" -- 2.1.4 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH V2 1/2] Bound violation handling preparation. @ 2015-12-17 17:06 Walfred Tedeschi 2015-12-17 17:06 ` [PATCH V2 2/2] Bound violation handling Walfred Tedeschi 0 siblings, 1 reply; 4+ messages in thread From: Walfred Tedeschi @ 2015-12-17 17:06 UTC (permalink / raw) To: palves, brobecker; +Cc: gdb-patches, Walfred Tedeschi The current order of the observers doe not allow evaluations of siginfo while stopping. Order has to be changed to allow evaluation during the printing process. 2015-12-15 Walfred Tedeschi <walfred.tedeschi@intel.com> * infrun.c (normal_stop): Change observers placement within the function. --- gdb/infrun.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/gdb/infrun.c b/gdb/infrun.c index f9bb411..2ed807c 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -8174,9 +8174,6 @@ normal_stop (void) instead of after. */ update_thread_list (); - if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal) - observer_notify_signal_received (inferior_thread ()->suspend.stop_signal); - /* As with the notification of thread events, we want to delay notifying the user that we've switched thread context until the inferior actually stops. @@ -8282,6 +8279,9 @@ normal_stop (void) do_cleanups (old_chain); } + if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal) + observer_notify_signal_received (inferior_thread ()->suspend.stop_signal); + /* Notify observers about the stop. This is where the interpreters print the stop event. */ if (!ptid_equal (inferior_ptid, null_ptid)) -- 2.1.4 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH V2 2/2] Bound violation handling. 2015-12-17 17:06 [PATCH V2 1/2] Bound violation handling preparation Walfred Tedeschi @ 2015-12-17 17:06 ` Walfred Tedeschi 2015-12-17 17:12 ` Tedeschi, Walfred 0 siblings, 1 reply; 4+ messages in thread From: Walfred Tedeschi @ 2015-12-17 17:06 UTC (permalink / raw) To: palves, brobecker; +Cc: gdb-patches, Walfred Tedeschi With Intel(R) Memory Protection Extensions it was introduced the concept of boundary violation. A boundary violations is presented to the inferior as a segmentation fault having as sigcode the value 3. This patch adds a handler for a boundary violation extending the information displayed when a bound violation is presented to the inferior (segfault with code 3). In this case the debugger will also display the kind of violation upper or lower the violated bounds and the address accessed. The usual output of a segfault, which is indeed a bound violation will be presented to the user as: Program received signal SIGSEGV, Segmentation fault upper bound violation - bounds {lbound = 0x603010, ubound = 0x603023} accessing 0x60302f. 0x0000000000400d7c in upper (p=0x603010, a=0x603030, b=0x603050, c=0x603070, d=0x603090, len=7) at i386-mpx-sigsegv.c:68 68 value = *(p + len); In mi mode the output of a segfault which is indeed a bound violation will be presented as: *stopped,reason="signal-received",signal-name="SIGSEGV", signal-meaning="Segmentation fault",sigcode-meaning="upper bound violation", lower-bound="0x603010",upper-bound="0x603023",bound-access="0x60302f", frame={addr="0x0000000000400d7c",func="upper",args=[{name="p", value="0x603010"},{name="a",value="0x603030"},{name="b",value="0x603050"}, {name="c",value="0x603070"},{name="d",value="0x603090"}, {name="len",value="7"}],file="i386-mpx-sigsegv.c", fullname="i386-mpx-sigsegv.c",line="68"},thread-id="1", stopped-threads="all",core="6" Changelog: 2015-12-15 Walfred Tedeschi <walfred.tedeschi@intel.com> * amd64-linux-tdep.c (amd64_linux_init_abi_common): Add handler for bound violation signal. * gdbarch.sh (bound_violation_handler): New. * i386-linux-tdep.c (i386_mpx_bound_violation_handler): New. (i386_linux_init_abi): Use i386_mpx_bound_violation_handler. * i386-linux-tdep.h (i386_mpx_bound_violation_handler) New. * i386-tdep.c (i386_mpx_enabled): Add as external. * i386-tdep.c (i386_mpx_enabled): Add as external. * infrun.c (process_segmentation_faults): New. (print_signal_received_reason): Use process_segmentation_faults. testsuite/gdb.arch * i386-mpx-sigsegv.c: New. * i386-mpx-sigsegv.exp: New. * i386-mpx-simple_segv.c: New. * i386-mpx-simple_segv.exp: New. --- gdb/amd64-linux-tdep.c | 3 + gdb/gdbarch.c | 32 ++++++ gdb/gdbarch.h | 11 +++ gdb/gdbarch.sh | 6 ++ gdb/i386-linux-tdep.c | 39 ++++++++ gdb/i386-linux-tdep.h | 5 + gdb/i386-tdep.c | 4 +- gdb/i386-tdep.h | 3 + gdb/infrun.c | 27 +++++ gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c | 120 ++++++++++++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp | 87 ++++++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c | 66 +++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp | 126 ++++++++++++++++++++++++ 13 files changed, 526 insertions(+), 3 deletions(-) create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c index bde751f..954855b 100644 --- a/gdb/amd64-linux-tdep.c +++ b/gdb/amd64-linux-tdep.c @@ -1840,6 +1840,9 @@ amd64_linux_init_abi_common(struct gdbarch_info info, struct gdbarch *gdbarch) set_gdbarch_process_record_signal (gdbarch, amd64_linux_record_signal); set_gdbarch_get_siginfo_type (gdbarch, x86_get_siginfo_type_with_fields); + set_gdbarch_bound_violation_handler(gdbarch, + i386_mpx_bound_violation_handler); + } static void diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c index f04eef9..42eb4db 100644 --- a/gdb/gdbarch.c +++ b/gdb/gdbarch.c @@ -189,6 +189,7 @@ struct gdbarch int num_pseudo_regs; gdbarch_ax_pseudo_register_collect_ftype *ax_pseudo_register_collect; gdbarch_ax_pseudo_register_push_stack_ftype *ax_pseudo_register_push_stack; + gdbarch_bound_violation_handler_ftype *bound_violation_handler; int sp_regnum; int pc_regnum; int ps_regnum; @@ -531,6 +532,7 @@ verify_gdbarch (struct gdbarch *gdbarch) /* Skip verify of num_pseudo_regs, invalid_p == 0 */ /* Skip verify of ax_pseudo_register_collect, has predicate. */ /* Skip verify of ax_pseudo_register_push_stack, has predicate. */ + /* Skip verify of bound_violation_handler, has predicate. */ /* Skip verify of sp_regnum, invalid_p == 0 */ /* Skip verify of pc_regnum, invalid_p == 0 */ /* Skip verify of ps_regnum, invalid_p == 0 */ @@ -773,6 +775,12 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file) "gdbarch_dump: bits_big_endian = %s\n", plongest (gdbarch->bits_big_endian)); fprintf_unfiltered (file, + "gdbarch_dump: gdbarch_bound_violation_handler_p() = %d\n", + gdbarch_bound_violation_handler_p (gdbarch)); + fprintf_unfiltered (file, + "gdbarch_dump: bound_violation_handler = <%s>\n", + host_address_to_string (gdbarch->bound_violation_handler)); + fprintf_unfiltered (file, "gdbarch_dump: breakpoint_from_pc = <%s>\n", host_address_to_string (gdbarch->breakpoint_from_pc)); fprintf_unfiltered (file, @@ -1986,6 +1994,30 @@ set_gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, } int +gdbarch_bound_violation_handler_p (struct gdbarch *gdbarch) +{ + gdb_assert (gdbarch != NULL); + return gdbarch->bound_violation_handler != NULL; +} + +void +gdbarch_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out *uiout) +{ + gdb_assert (gdbarch != NULL); + gdb_assert (gdbarch->bound_violation_handler != NULL); + if (gdbarch_debug >= 2) + fprintf_unfiltered (gdb_stdlog, "gdbarch_bound_violation_handler called\n"); + gdbarch->bound_violation_handler (gdbarch, uiout); +} + +void +set_gdbarch_bound_violation_handler (struct gdbarch *gdbarch, + gdbarch_bound_violation_handler_ftype bound_violation_handler) +{ + gdbarch->bound_violation_handler = bound_violation_handler; +} + +int gdbarch_sp_regnum (struct gdbarch *gdbarch) { gdb_assert (gdbarch != NULL); diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h index b9b2290..f1436d8 100644 --- a/gdb/gdbarch.h +++ b/gdb/gdbarch.h @@ -63,6 +63,7 @@ struct ravenscar_arch_ops; struct elf_internal_linux_prpsinfo; struct mem_range; struct syscalls_info; +struct ui_out; #include "regcache.h" @@ -299,6 +300,16 @@ typedef int (gdbarch_ax_pseudo_register_push_stack_ftype) (struct gdbarch *gdbar extern int gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, struct agent_expr *ax, int reg); extern void set_gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, gdbarch_ax_pseudo_register_push_stack_ftype *ax_pseudo_register_push_stack); +/* Function called when a segmentation fault signal is received by the inferior, + having sigcode = 3 (SIG_CODE_BOUNDARY_FAULT). + UIOUT is the output stream where the handler will place information. */ + +extern int gdbarch_bound_violation_handler_p (struct gdbarch *gdbarch); + +typedef void (gdbarch_bound_violation_handler_ftype) (struct gdbarch *gdbarch, struct ui_out *uiout); +extern void gdbarch_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out *uiout); +extern void set_gdbarch_bound_violation_handler (struct gdbarch *gdbarch, gdbarch_bound_violation_handler_ftype *bound_violation_handler); + /* GDB's standard (or well known) register numbers. These can map onto a real register or a pseudo (computed) register or not be defined at all (-1). diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh index 236ce41..f36f0e0 100755 --- a/gdb/gdbarch.sh +++ b/gdb/gdbarch.sh @@ -446,6 +446,11 @@ M:int:ax_pseudo_register_collect:struct agent_expr *ax, int reg:ax, reg # Return -1 if something goes wrong, 0 otherwise. M:int:ax_pseudo_register_push_stack:struct agent_expr *ax, int reg:ax, reg +# Function called when a segmentation fault signal is received by the inferior, +# having sigcode = 3 (SIG_CODE_BOUNDARY_FAULT). +# UIOUT is the output stream where the handler will place information. +M:void:bound_violation_handler:struct ui_out *uiout:uiout + # GDB's standard (or well known) register numbers. These can map onto # a real register or a pseudo (computed) register or not be defined at # all (-1). @@ -1247,6 +1252,7 @@ struct ravenscar_arch_ops; struct elf_internal_linux_prpsinfo; struct mem_range; struct syscalls_info; +struct ui_out; #include "regcache.h" diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c index 766f193..2a4e875 100644 --- a/gdb/i386-linux-tdep.c +++ b/gdb/i386-linux-tdep.c @@ -30,6 +30,7 @@ #include "i386-tdep.h" #include "i386-linux-tdep.h" #include "linux-tdep.h" +#include "utils.h" #include "glibc-tdep.h" #include "solib-svr4.h" #include "symtab.h" @@ -384,6 +385,41 @@ i386_canonicalize_syscall (int syscall) return gdb_sys_no_syscall; } +void +i386_mpx_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out *uiout) +{ + CORE_ADDR lower_bound, upper_bound, access; + int is_upper; + + if (!i386_mpx_enabled ()) + return; + + lower_bound + = parse_and_eval_long ("$_siginfo._sifields._sigfault._addr_bnd._lower"); + upper_bound + = parse_and_eval_long ("$_siginfo._sifields._sigfault._addr_bnd._upper"); + access + = parse_and_eval_long ("$_siginfo._sifields._sigfault.si_addr"); + is_upper = (access > upper_bound ? 1 : 0); + + ui_out_text (uiout, "\n"); + if (is_upper) + ui_out_field_string (uiout, "sigcode-meaning", "upper bound violation"); + else + ui_out_field_string (uiout, "sigcode-meaning", "lower bound violation"); + + ui_out_text (uiout, " - bounds {lbound = "); + ui_out_field_fmt (uiout,"lower-bound", "%s", paddress (gdbarch, lower_bound)); + ui_out_text (uiout, ", ubound = "); + ui_out_field_fmt (uiout,"upper-bound", "%s", paddress (gdbarch, upper_bound)); + ui_out_text (uiout, "}"); + ui_out_text (uiout, " accessing "); + ui_out_field_fmt (uiout,"bound-access", "%s", paddress (gdbarch, access)); + + return; +} + + /* Parse the arguments of current system call instruction and record the values of the registers and memory that will be changed into "record_arch_list". This instruction is "int 0x80" (Linux @@ -1002,6 +1038,9 @@ i386_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) i386_linux_get_syscall_number); set_gdbarch_get_siginfo_type (gdbarch, x86_get_siginfo_type_with_fields); + set_gdbarch_bound_violation_handler(gdbarch, + i386_mpx_bound_violation_handler); + } /* Provide a prototype to silence -Wmissing-prototypes. */ diff --git a/gdb/i386-linux-tdep.h b/gdb/i386-linux-tdep.h index f42bf7a..78efa76 100644 --- a/gdb/i386-linux-tdep.h +++ b/gdb/i386-linux-tdep.h @@ -37,6 +37,11 @@ /* Get XSAVE extended state xcr0 from core dump. */ extern uint64_t i386_linux_core_read_xcr0 (bfd *abfd); +/* Handles and displays information related to the MPX bound violation + to the user. */ +void +i386_mpx_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out *uiout); + /* Linux target description. */ extern struct target_desc *tdesc_i386_linux; extern struct target_desc *tdesc_i386_mmx_linux; diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c index ebb21fc..60be128 100644 --- a/gdb/i386-tdep.c +++ b/gdb/i386-tdep.c @@ -8651,9 +8651,7 @@ i386_mpx_bd_base (void) return ret & MPX_BASE_MASK; } -/* Check if the current target is MPX enabled. */ - -static int +int i386_mpx_enabled (void) { const struct gdbarch_tdep *tdep = gdbarch_tdep (get_current_arch ()); diff --git a/gdb/i386-tdep.h b/gdb/i386-tdep.h index 95288ba..4e81288 100644 --- a/gdb/i386-tdep.h +++ b/gdb/i386-tdep.h @@ -420,6 +420,9 @@ extern int i386_process_record (struct gdbarch *gdbarch, struct regcache *regcache, CORE_ADDR addr); extern const struct target_desc *i386_target_description (uint64_t xcr0); +/* Verify if target is MPX enabled. */ +extern int i386_mpx_enabled (void); + \f /* Functions and variables exported from i386bsd-tdep.c. */ diff --git a/gdb/infrun.c b/gdb/infrun.c index 2ed807c..ec3720d 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -7893,6 +7893,29 @@ print_exited_reason (struct ui_out *uiout, int exitstatus) } } +/* Value of the sigcode in case of a boundary fault. */ + +#define SIG_CODE_BONDARY_FAULT 3 + +/* Verifies if a received segmentation fault is a boundary fault. + In the case it is it calls the architecture dependent function + to handle the boundary fault. */ + +static void +handle_segmentation_faults (struct ui_out *uiout) +{ + long sig_code; + struct regcache *regcache = get_current_regcache (); + struct gdbarch *gdbarch = get_regcache_arch (regcache); + + set_running (user_visible_resume_ptid (1), 0); + sig_code = parse_and_eval_long ("$_siginfo.si_code\n"); + + if (sig_code == SIG_CODE_BONDARY_FAULT + && gdbarch_bound_violation_handler_p (gdbarch)) + gdbarch_bound_violation_handler (gdbarch, uiout); +} + void print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal) { @@ -7922,6 +7945,10 @@ print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal) annotate_signal_string (); ui_out_field_string (uiout, "signal-meaning", gdb_signal_to_string (siggnal)); + + if (siggnal == GDB_SIGNAL_SEGV) + handle_segmentation_faults (uiout); + annotate_signal_string_end (); } ui_out_text (uiout, ".\n"); diff --git a/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c new file mode 100644 index 0000000..3bbd5b8 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c @@ -0,0 +1,120 @@ +/* Copyright 2015 Free Software Foundation, Inc. + + Contributed by Intel Corp. <walfred.tedeschi@intel.com> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "x86-cpuid.h" +#include <stdio.h> + +#define OUR_SIZE 5 + +int gx[OUR_SIZE]; +int ga[OUR_SIZE]; +int gb[OUR_SIZE]; +int gc[OUR_SIZE]; +int gd[OUR_SIZE]; + +unsigned int +have_mpx (void) +{ + unsigned int eax, ebx, ecx, edx; + + if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx)) + return 0; + + if ((ecx & bit_OSXSAVE) == bit_OSXSAVE) + { + if (__get_cpuid_max (0, NULL) < 7) + return 0; + + __cpuid_count (7, 0, eax, ebx, ecx, edx); + + if ((ebx & bit_MPX) == bit_MPX) + return 1; + else + return 0; + } + return 0; +} + +int +bp1 (int value) +{ + return 1; +} + +int +bp2 (int value) +{ + return 1; +} + +void +upper (int * p, int * a, int * b, int * c, int * d, int len) +{ + int value; + value = *(p + len); + value = *(a + len); + value = *(b + len); + value = *(c + len); + value = *(d + len); +} + +void +lower (int * p, int * a, int * b, int * c, int * d, int len) +{ + int value; + value = *(p - len); + value = *(a - len); + value = *(b - len); + value = *(c - len); + bp2 (value); + value = *(d - len); +} + +int +main (void) +{ + if (have_mpx ()) + { + int sx[OUR_SIZE]; + int sa[OUR_SIZE]; + int sb[OUR_SIZE]; + int sc[OUR_SIZE]; + int sd[OUR_SIZE]; + int *x, *a, *b, *c, *d; + + x = calloc (OUR_SIZE, sizeof (int)); + a = calloc (OUR_SIZE, sizeof (int)); + b = calloc (OUR_SIZE, sizeof (int)); + c = calloc (OUR_SIZE, sizeof (int)); + d = calloc (OUR_SIZE, sizeof (int)); + + upper (x, a, b, c, d, OUR_SIZE + 2); + upper (sx, sa, sb, sc, sd, OUR_SIZE + 2); + upper (gx, ga, gb, gc, gd, OUR_SIZE + 2); + lower (x, a, b, c, d, 1); + lower (sx, sa, sb, sc, sd, 1); + bp1 (*x); + lower (gx, ga, gb, gc, gd, 1); + + free (x); + free (a); + free (b); + free (c); + free (d); + } + return 0; +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp new file mode 100644 index 0000000..2ddd331 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp @@ -0,0 +1,87 @@ +# Copyright 2015 Free Software Foundation, Inc. +# +# Contributed by Intel Corp. <walfred.tedeschi@intel.com> +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + + +if { ![istarget i?86-*-*] && ![istarget x86_64-*-* ] } { + verbose "Skipping x86 MPX tests." + return +} + +standard_testfile + +set comp_flags "-mmpx -fcheck-pointer-bounds -I${srcdir}/../nat/" + +if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} \ + [list debug nowarnings additional_flags=${comp_flags}]] } { + return -1 +} + +if ![runto_main] { + untested "could not run to main" + return -1 +} + +gdb_test_multiple "print have_mpx ()" "have mpx" { + -re ".. = 1\r\n$gdb_prompt " { + pass "check whether processor supports MPX" + } + -re ".. = 0\r\n$gdb_prompt " { + verbose "processor does not support MPX; skipping MPX tests" + return + } +} + +set segv_lower_bound ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nlower bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +set segv_upper_bound ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +for {set i 0} {$i < 15} {incr i} { + set message "MPX signal segv Upper: ${i}" + gdb_test_multiple "continue" "$message ${i}" { + -re $segv_upper_bound { + pass "$message" + } + -re ".*$inferior_exited_re normally.*$gdb_prompt $" { + fail "$message" + break + } + } + + gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "$message: should be in upper" +} + +for {set i 0} {$i < 15} {incr i} { + set message "MPX signal segv Lower: ${i}" + gdb_test_multiple "continue" "$message ${i}" { + -re $segv_lower_bound { + pass "$message ${i}" + } + -re ".*$inferior_exited_re normally.*$gdb_prompt $" { + fail "$message ${i}" + break + } + } + gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in lower.*"\ + "$message: should be in lower" +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c new file mode 100644 index 0000000..2c187d0 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c @@ -0,0 +1,66 @@ +/* Copyright 2012 Free Software Foundation, Inc. + + Contributed by Intel Corp. <walfred.tedeschi@intel.com> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "x86-cpuid.h" +#include <stdio.h> + +#define OUR_SIZE 5 + +unsigned int +have_mpx (void) +{ + unsigned int eax, ebx, ecx, edx; + + if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx)) + return 0; + + if ((ecx & bit_OSXSAVE) == bit_OSXSAVE) + { + if (__get_cpuid_max (0, NULL) < 7) + return 0; + + __cpuid_count (7, 0, eax, ebx, ecx, edx); + + if ((ebx & bit_MPX) == bit_MPX) + return 1; + else + return 0; + } + return 0; +} + +void +upper (int * p, int len) +{ + int value; + len++; /* b0-size-test. */ + value = *(p + len); +} + +int +main (void) +{ + if (have_mpx ()) + { + int a = 0; /* Dummy variable for debugging purposes. */ + int sx[OUR_SIZE]; + a++; /* register-eval. */ + upper (sx, OUR_SIZE + 2); + return sx[1]; + } + return 0; +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp new file mode 100644 index 0000000..7f0c7e4 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp @@ -0,0 +1,126 @@ +# Copyright 2015 Free Software Foundation, Inc. +# +# Contributed by Intel Corp. <walfred.tedeschi@intel.com> +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# Testing handle setup together with boundary violation signals. +# +# Some states are not allowed as reported on the manual, as noprint +# implies nostop, but nostop might print. +# +# Caveat: Setting the handle to nopass, ends up in a endless loop. + +if { ![istarget i?86-*-*] && ![istarget x86_64-*-* ] } { + verbose "Skipping x86 MPX tests." + return +} + +standard_testfile + +set comp_flags "-mmpx -fcheck-pointer-bounds -I${srcdir}/../nat/" + +if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} \ + [list debug nowarnings additional_flags=${comp_flags}]] } { + return -1 +} + +if ![runto_main] { + untested "could not run to main" + return -1 +} + +send_gdb "print have_mpx ()\r" +gdb_expect { + -re ".. = 1\r\n$gdb_prompt " { + pass "check whether processor supports MPX" + } + -re ".. = 0\r\n$gdb_prompt " { + verbose "processor does not support MPX; skipping MPX tests" + return + } +} + +set segv_bound_with_prompt ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +set segv_bound_with_exit ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$inferior_exited_re.*" + +# Using the handler for SIGSEGV as "print pass stop" +set parameters "print pass stop" +runto_main +send_gdb "handle SIGSEGV $parameters\n" +send_gdb "continue\n" + +gdb_expect { + -re $segv_bound_with_prompt { + pass $parameters + } +} +gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "should be in upper; $parameters" + +# Using the handler for SIGSEGV as "print pass nostop" +set parameters "print pass nostop" +runto_main + +gdb_test "handle SIGSEGV $parameters" "" "Setting\ +the handler for segfault 0" + +gdb_test_multiple "continue" "test 0" { + -re $segv_bound_with_exit { + pass $parameters + } + -re "$gdb_prompt $" { + fail $parameters + } +} + +gdb_test "where" "No stack." "no inferior $parameters" + +# Using the handler for SIGSEGV as "print nopass stop" +set parameters "print nopass stop" + +runto_main +gdb_test "handle SIGSEGV $parameters" "" "Setting\ +the handler for segfault 1" + +gdb_test_multiple "continue" "test 1" { + -re $segv_bound_with_prompt { + pass $parameters + } +} + +gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "should be in upper $parameters" + +# print nopass stop +set parameters "noprint pass nostop" +runto_main + +gdb_test "handle SIGSEGV $parameters" "" "Setting\ +the handler for segfault 2" + +gdb_test_multiple "continue" "test 2" { + -re "Continuing\..*$inferior_exited_re.*" { + pass $parameters + } +} + +gdb_test "where" "No stack." "no inferior $parameters" -- 2.1.4 ^ permalink raw reply [flat|nested] 4+ messages in thread
* RE: [PATCH V2 2/2] Bound violation handling. 2015-12-17 17:06 ` [PATCH V2 2/2] Bound violation handling Walfred Tedeschi @ 2015-12-17 17:12 ` Tedeschi, Walfred 0 siblings, 0 replies; 4+ messages in thread From: Tedeschi, Walfred @ 2015-12-17 17:12 UTC (permalink / raw) To: palves, brobecker; +Cc: gdb-patches Joel, Pedro and all, Please disregard this review! There is code missing related to the evaluations. I have added also a try and catch block that is not in. Thanks and regards, -Fred -----Original Message----- From: Tedeschi, Walfred Sent: Thursday, December 17, 2015 6:06 PM To: palves@redhat.com; brobecker@adacore.com Cc: gdb-patches@sourceware.org; Tedeschi, Walfred Subject: [PATCH V2 2/2] Bound violation handling. With Intel(R) Memory Protection Extensions it was introduced the concept of boundary violation. A boundary violations is presented to the inferior as a segmentation fault having as sigcode the value 3. This patch adds a handler for a boundary violation extending the information displayed when a bound violation is presented to the inferior (segfault with code 3). In this case the debugger will also display the kind of violation upper or lower the violated bounds and the address accessed. The usual output of a segfault, which is indeed a bound violation will be presented to the user as: Program received signal SIGSEGV, Segmentation fault upper bound violation - bounds {lbound = 0x603010, ubound = 0x603023} accessing 0x60302f. 0x0000000000400d7c in upper (p=0x603010, a=0x603030, b=0x603050, c=0x603070, d=0x603090, len=7) at i386-mpx-sigsegv.c:68 68 value = *(p + len); In mi mode the output of a segfault which is indeed a bound violation will be presented as: *stopped,reason="signal-received",signal-name="SIGSEGV", signal-meaning="Segmentation fault",sigcode-meaning="upper bound violation", lower-bound="0x603010",upper-bound="0x603023",bound-access="0x60302f", frame={addr="0x0000000000400d7c",func="upper",args=[{name="p", value="0x603010"},{name="a",value="0x603030"},{name="b",value="0x603050"}, {name="c",value="0x603070"},{name="d",value="0x603090"}, {name="len",value="7"}],file="i386-mpx-sigsegv.c", fullname="i386-mpx-sigsegv.c",line="68"},thread-id="1", stopped-threads="all",core="6" Changelog: 2015-12-15 Walfred Tedeschi <walfred.tedeschi@intel.com> * amd64-linux-tdep.c (amd64_linux_init_abi_common): Add handler for bound violation signal. * gdbarch.sh (bound_violation_handler): New. * i386-linux-tdep.c (i386_mpx_bound_violation_handler): New. (i386_linux_init_abi): Use i386_mpx_bound_violation_handler. * i386-linux-tdep.h (i386_mpx_bound_violation_handler) New. * i386-tdep.c (i386_mpx_enabled): Add as external. * i386-tdep.c (i386_mpx_enabled): Add as external. * infrun.c (process_segmentation_faults): New. (print_signal_received_reason): Use process_segmentation_faults. testsuite/gdb.arch * i386-mpx-sigsegv.c: New. * i386-mpx-sigsegv.exp: New. * i386-mpx-simple_segv.c: New. * i386-mpx-simple_segv.exp: New. --- gdb/amd64-linux-tdep.c | 3 + gdb/gdbarch.c | 32 ++++++ gdb/gdbarch.h | 11 +++ gdb/gdbarch.sh | 6 ++ gdb/i386-linux-tdep.c | 39 ++++++++ gdb/i386-linux-tdep.h | 5 + gdb/i386-tdep.c | 4 +- gdb/i386-tdep.h | 3 + gdb/infrun.c | 27 +++++ gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c | 120 ++++++++++++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp | 87 ++++++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c | 66 +++++++++++++ gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp | 126 ++++++++++++++++++++++++ 13 files changed, 526 insertions(+), 3 deletions(-) create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c create mode 100644 gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c index bde751f..954855b 100644 --- a/gdb/amd64-linux-tdep.c +++ b/gdb/amd64-linux-tdep.c @@ -1840,6 +1840,9 @@ amd64_linux_init_abi_common(struct gdbarch_info info, struct gdbarch *gdbarch) set_gdbarch_process_record_signal (gdbarch, amd64_linux_record_signal); set_gdbarch_get_siginfo_type (gdbarch, x86_get_siginfo_type_with_fields); + set_gdbarch_bound_violation_handler(gdbarch, + + i386_mpx_bound_violation_handler); + } static void diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c index f04eef9..42eb4db 100644 --- a/gdb/gdbarch.c +++ b/gdb/gdbarch.c @@ -189,6 +189,7 @@ struct gdbarch int num_pseudo_regs; gdbarch_ax_pseudo_register_collect_ftype *ax_pseudo_register_collect; gdbarch_ax_pseudo_register_push_stack_ftype *ax_pseudo_register_push_stack; + gdbarch_bound_violation_handler_ftype *bound_violation_handler; int sp_regnum; int pc_regnum; int ps_regnum; @@ -531,6 +532,7 @@ verify_gdbarch (struct gdbarch *gdbarch) /* Skip verify of num_pseudo_regs, invalid_p == 0 */ /* Skip verify of ax_pseudo_register_collect, has predicate. */ /* Skip verify of ax_pseudo_register_push_stack, has predicate. */ + /* Skip verify of bound_violation_handler, has predicate. */ /* Skip verify of sp_regnum, invalid_p == 0 */ /* Skip verify of pc_regnum, invalid_p == 0 */ /* Skip verify of ps_regnum, invalid_p == 0 */ @@ -773,6 +775,12 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file) "gdbarch_dump: bits_big_endian = %s\n", plongest (gdbarch->bits_big_endian)); fprintf_unfiltered (file, + "gdbarch_dump: gdbarch_bound_violation_handler_p() = %d\n", + gdbarch_bound_violation_handler_p (gdbarch)); + fprintf_unfiltered (file, + "gdbarch_dump: bound_violation_handler = <%s>\n", + host_address_to_string + (gdbarch->bound_violation_handler)); + fprintf_unfiltered (file, "gdbarch_dump: breakpoint_from_pc = <%s>\n", host_address_to_string (gdbarch->breakpoint_from_pc)); fprintf_unfiltered (file, @@ -1986,6 +1994,30 @@ set_gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, } int +gdbarch_bound_violation_handler_p (struct gdbarch *gdbarch) { + gdb_assert (gdbarch != NULL); + return gdbarch->bound_violation_handler != NULL; } + +void +gdbarch_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out +*uiout) { + gdb_assert (gdbarch != NULL); + gdb_assert (gdbarch->bound_violation_handler != NULL); + if (gdbarch_debug >= 2) + fprintf_unfiltered (gdb_stdlog, "gdbarch_bound_violation_handler +called\n"); + gdbarch->bound_violation_handler (gdbarch, uiout); } + +void +set_gdbarch_bound_violation_handler (struct gdbarch *gdbarch, + +gdbarch_bound_violation_handler_ftype bound_violation_handler) { + gdbarch->bound_violation_handler = bound_violation_handler; } + +int gdbarch_sp_regnum (struct gdbarch *gdbarch) { gdb_assert (gdbarch != NULL); diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h index b9b2290..f1436d8 100644 --- a/gdb/gdbarch.h +++ b/gdb/gdbarch.h @@ -63,6 +63,7 @@ struct ravenscar_arch_ops; struct elf_internal_linux_prpsinfo; struct mem_range; struct syscalls_info; +struct ui_out; #include "regcache.h" @@ -299,6 +300,16 @@ typedef int (gdbarch_ax_pseudo_register_push_stack_ftype) (struct gdbarch *gdbar extern int gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, struct agent_expr *ax, int reg); extern void set_gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, gdbarch_ax_pseudo_register_push_stack_ftype *ax_pseudo_register_push_stack); +/* Function called when a segmentation fault signal is received by the inferior, + having sigcode = 3 (SIG_CODE_BOUNDARY_FAULT). + UIOUT is the output stream where the handler will place information. +*/ + +extern int gdbarch_bound_violation_handler_p (struct gdbarch *gdbarch); + +typedef void (gdbarch_bound_violation_handler_ftype) (struct gdbarch +*gdbarch, struct ui_out *uiout); extern void +gdbarch_bound_violation_handler (struct gdbarch *gdbarch, struct ui_out +*uiout); extern void set_gdbarch_bound_violation_handler (struct +gdbarch *gdbarch, gdbarch_bound_violation_handler_ftype +*bound_violation_handler); + /* GDB's standard (or well known) register numbers. These can map onto a real register or a pseudo (computed) register or not be defined at all (-1). diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh index 236ce41..f36f0e0 100755 --- a/gdb/gdbarch.sh +++ b/gdb/gdbarch.sh @@ -446,6 +446,11 @@ M:int:ax_pseudo_register_collect:struct agent_expr *ax, int reg:ax, reg # Return -1 if something goes wrong, 0 otherwise. M:int:ax_pseudo_register_push_stack:struct agent_expr *ax, int reg:ax, reg +# Function called when a segmentation fault signal is received by the +inferior, # having sigcode = 3 (SIG_CODE_BOUNDARY_FAULT). +# UIOUT is the output stream where the handler will place information. +M:void:bound_violation_handler:struct ui_out *uiout:uiout + # GDB's standard (or well known) register numbers. These can map onto # a real register or a pseudo (computed) register or not be defined at # all (-1). @@ -1247,6 +1252,7 @@ struct ravenscar_arch_ops; struct elf_internal_linux_prpsinfo; struct mem_range; struct syscalls_info; +struct ui_out; #include "regcache.h" diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c index 766f193..2a4e875 100644 --- a/gdb/i386-linux-tdep.c +++ b/gdb/i386-linux-tdep.c @@ -30,6 +30,7 @@ #include "i386-tdep.h" #include "i386-linux-tdep.h" #include "linux-tdep.h" +#include "utils.h" #include "glibc-tdep.h" #include "solib-svr4.h" #include "symtab.h" @@ -384,6 +385,41 @@ i386_canonicalize_syscall (int syscall) return gdb_sys_no_syscall; } +void +i386_mpx_bound_violation_handler (struct gdbarch *gdbarch, struct +ui_out *uiout) { + CORE_ADDR lower_bound, upper_bound, access; + int is_upper; + + if (!i386_mpx_enabled ()) + return; + + lower_bound + = parse_and_eval_long + ("$_siginfo._sifields._sigfault._addr_bnd._lower"); + upper_bound + = parse_and_eval_long + ("$_siginfo._sifields._sigfault._addr_bnd._upper"); + access + = parse_and_eval_long ("$_siginfo._sifields._sigfault.si_addr"); + is_upper = (access > upper_bound ? 1 : 0); + + ui_out_text (uiout, "\n"); + if (is_upper) + ui_out_field_string (uiout, "sigcode-meaning", "upper bound + violation"); else + ui_out_field_string (uiout, "sigcode-meaning", "lower bound + violation"); + + ui_out_text (uiout, " - bounds {lbound = "); ui_out_field_fmt + (uiout,"lower-bound", "%s", paddress (gdbarch, lower_bound)); + ui_out_text (uiout, ", ubound = "); ui_out_field_fmt + (uiout,"upper-bound", "%s", paddress (gdbarch, upper_bound)); + ui_out_text (uiout, "}"); ui_out_text (uiout, " accessing "); + ui_out_field_fmt (uiout,"bound-access", "%s", paddress (gdbarch, + access)); + + return; +} + + /* Parse the arguments of current system call instruction and record the values of the registers and memory that will be changed into "record_arch_list". This instruction is "int 0x80" (Linux @@ -1002,6 +1038,9 @@ i386_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) i386_linux_get_syscall_number); set_gdbarch_get_siginfo_type (gdbarch, x86_get_siginfo_type_with_fields); + set_gdbarch_bound_violation_handler(gdbarch, + + i386_mpx_bound_violation_handler); + } /* Provide a prototype to silence -Wmissing-prototypes. */ diff --git a/gdb/i386-linux-tdep.h b/gdb/i386-linux-tdep.h index f42bf7a..78efa76 100644 --- a/gdb/i386-linux-tdep.h +++ b/gdb/i386-linux-tdep.h @@ -37,6 +37,11 @@ /* Get XSAVE extended state xcr0 from core dump. */ extern uint64_t i386_linux_core_read_xcr0 (bfd *abfd); +/* Handles and displays information related to the MPX bound violation + to the user. */ +void +i386_mpx_bound_violation_handler (struct gdbarch *gdbarch, struct +ui_out *uiout); + /* Linux target description. */ extern struct target_desc *tdesc_i386_linux; extern struct target_desc *tdesc_i386_mmx_linux; diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c index ebb21fc..60be128 100644 --- a/gdb/i386-tdep.c +++ b/gdb/i386-tdep.c @@ -8651,9 +8651,7 @@ i386_mpx_bd_base (void) return ret & MPX_BASE_MASK; } -/* Check if the current target is MPX enabled. */ - -static int +int i386_mpx_enabled (void) { const struct gdbarch_tdep *tdep = gdbarch_tdep (get_current_arch ()); diff --git a/gdb/i386-tdep.h b/gdb/i386-tdep.h index 95288ba..4e81288 100644 --- a/gdb/i386-tdep.h +++ b/gdb/i386-tdep.h @@ -420,6 +420,9 @@ extern int i386_process_record (struct gdbarch *gdbarch, struct regcache *regcache, CORE_ADDR addr); extern const struct target_desc *i386_target_description (uint64_t xcr0); +/* Verify if target is MPX enabled. */ extern int i386_mpx_enabled +(void); + /* Functions and variables exported from i386bsd-tdep.c. */ diff --git a/gdb/infrun.c b/gdb/infrun.c index 2ed807c..ec3720d 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -7893,6 +7893,29 @@ print_exited_reason (struct ui_out *uiout, int exitstatus) } } +/* Value of the sigcode in case of a boundary fault. */ + +#define SIG_CODE_BONDARY_FAULT 3 + +/* Verifies if a received segmentation fault is a boundary fault. + In the case it is it calls the architecture dependent function + to handle the boundary fault. */ + +static void +handle_segmentation_faults (struct ui_out *uiout) { + long sig_code; + struct regcache *regcache = get_current_regcache (); + struct gdbarch *gdbarch = get_regcache_arch (regcache); + + set_running (user_visible_resume_ptid (1), 0); sig_code = + parse_and_eval_long ("$_siginfo.si_code\n"); + + if (sig_code == SIG_CODE_BONDARY_FAULT + && gdbarch_bound_violation_handler_p (gdbarch)) + gdbarch_bound_violation_handler (gdbarch, uiout); } + void print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal) { @@ -7922,6 +7945,10 @@ print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal) annotate_signal_string (); ui_out_field_string (uiout, "signal-meaning", gdb_signal_to_string (siggnal)); + + if (siggnal == GDB_SIGNAL_SEGV) + handle_segmentation_faults (uiout); + annotate_signal_string_end (); } ui_out_text (uiout, ".\n"); diff --git a/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c new file mode 100644 index 0000000..3bbd5b8 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.c @@ -0,0 +1,120 @@ +/* Copyright 2015 Free Software Foundation, Inc. + + Contributed by Intel Corp. <walfred.tedeschi@intel.com> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see + <http://www.gnu.org/licenses/>. */ + +#include "x86-cpuid.h" +#include <stdio.h> + +#define OUR_SIZE 5 + +int gx[OUR_SIZE]; +int ga[OUR_SIZE]; +int gb[OUR_SIZE]; +int gc[OUR_SIZE]; +int gd[OUR_SIZE]; + +unsigned int +have_mpx (void) +{ + unsigned int eax, ebx, ecx, edx; + + if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx)) + return 0; + + if ((ecx & bit_OSXSAVE) == bit_OSXSAVE) + { + if (__get_cpuid_max (0, NULL) < 7) + return 0; + + __cpuid_count (7, 0, eax, ebx, ecx, edx); + + if ((ebx & bit_MPX) == bit_MPX) + return 1; + else + return 0; + } + return 0; +} + +int +bp1 (int value) +{ + return 1; +} + +int +bp2 (int value) +{ + return 1; +} + +void +upper (int * p, int * a, int * b, int * c, int * d, int len) { + int value; + value = *(p + len); + value = *(a + len); + value = *(b + len); + value = *(c + len); + value = *(d + len); +} + +void +lower (int * p, int * a, int * b, int * c, int * d, int len) { + int value; + value = *(p - len); + value = *(a - len); + value = *(b - len); + value = *(c - len); + bp2 (value); + value = *(d - len); +} + +int +main (void) +{ + if (have_mpx ()) + { + int sx[OUR_SIZE]; + int sa[OUR_SIZE]; + int sb[OUR_SIZE]; + int sc[OUR_SIZE]; + int sd[OUR_SIZE]; + int *x, *a, *b, *c, *d; + + x = calloc (OUR_SIZE, sizeof (int)); + a = calloc (OUR_SIZE, sizeof (int)); + b = calloc (OUR_SIZE, sizeof (int)); + c = calloc (OUR_SIZE, sizeof (int)); + d = calloc (OUR_SIZE, sizeof (int)); + + upper (x, a, b, c, d, OUR_SIZE + 2); + upper (sx, sa, sb, sc, sd, OUR_SIZE + 2); + upper (gx, ga, gb, gc, gd, OUR_SIZE + 2); + lower (x, a, b, c, d, 1); + lower (sx, sa, sb, sc, sd, 1); + bp1 (*x); + lower (gx, ga, gb, gc, gd, 1); + + free (x); + free (a); + free (b); + free (c); + free (d); + } + return 0; +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp new file mode 100644 index 0000000..2ddd331 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-sigsegv.exp @@ -0,0 +1,87 @@ +# Copyright 2015 Free Software Foundation, Inc. +# +# Contributed by Intel Corp. <walfred.tedeschi@intel.com> # # This +program is free software; you can redistribute it and/or modify # it +under the terms of the GNU General Public License as published by # the +Free Software Foundation; either version 3 of the License, or # (at +your option) any later version. +# +# This program is distributed in the hope that it will be useful, # but +WITHOUT ANY WARRANTY; without even the implied warranty of # +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU +General Public License for more details. +# +# You should have received a copy of the GNU General Public License # +along with this program. If not, see <http://www.gnu.org/licenses/>. + + +if { ![istarget i?86-*-*] && ![istarget x86_64-*-* ] } { + verbose "Skipping x86 MPX tests." + return +} + +standard_testfile + +set comp_flags "-mmpx -fcheck-pointer-bounds -I${srcdir}/../nat/" + +if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} \ +[list debug nowarnings additional_flags=${comp_flags}]] } { + return -1 +} + +if ![runto_main] { + untested "could not run to main" + return -1 +} + +gdb_test_multiple "print have_mpx ()" "have mpx" { + -re ".. = 1\r\n$gdb_prompt " { + pass "check whether processor supports MPX" + } + -re ".. = 0\r\n$gdb_prompt " { + verbose "processor does not support MPX; skipping MPX tests" + return + } +} + +set segv_lower_bound ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nlower bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +set segv_upper_bound ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +for {set i 0} {$i < 15} {incr i} { + set message "MPX signal segv Upper: ${i}" + gdb_test_multiple "continue" "$message ${i}" { + -re $segv_upper_bound { + pass "$message" + } + -re ".*$inferior_exited_re normally.*$gdb_prompt $" { + fail "$message" + break + } + } + + gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "$message: should be in upper" +} + +for {set i 0} {$i < 15} {incr i} { + set message "MPX signal segv Lower: ${i}" + gdb_test_multiple "continue" "$message ${i}" { + -re $segv_lower_bound { + pass "$message ${i}" + } + -re ".*$inferior_exited_re normally.*$gdb_prompt $" { + fail "$message ${i}" + break + } + } + gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in lower.*"\ + "$message: should be in lower" +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c new file mode 100644 index 0000000..2c187d0 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.c @@ -0,0 +1,66 @@ +/* Copyright 2012 Free Software Foundation, Inc. + + Contributed by Intel Corp. <walfred.tedeschi@intel.com> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see + <http://www.gnu.org/licenses/>. */ + +#include "x86-cpuid.h" +#include <stdio.h> + +#define OUR_SIZE 5 + +unsigned int +have_mpx (void) +{ + unsigned int eax, ebx, ecx, edx; + + if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx)) + return 0; + + if ((ecx & bit_OSXSAVE) == bit_OSXSAVE) + { + if (__get_cpuid_max (0, NULL) < 7) + return 0; + + __cpuid_count (7, 0, eax, ebx, ecx, edx); + + if ((ebx & bit_MPX) == bit_MPX) + return 1; + else + return 0; + } + return 0; +} + +void +upper (int * p, int len) +{ + int value; + len++; /* b0-size-test. */ + value = *(p + len); +} + +int +main (void) +{ + if (have_mpx ()) + { + int a = 0; /* Dummy variable for debugging purposes. */ + int sx[OUR_SIZE]; + a++; /* register-eval. */ + upper (sx, OUR_SIZE + 2); + return sx[1]; + } + return 0; +} diff --git a/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp new file mode 100644 index 0000000..7f0c7e4 --- /dev/null +++ b/gdb/testsuite/gdb.arch/i386-mpx-simple_segv.exp @@ -0,0 +1,126 @@ +# Copyright 2015 Free Software Foundation, Inc. +# +# Contributed by Intel Corp. <walfred.tedeschi@intel.com> # # This +program is free software; you can redistribute it and/or modify # it +under the terms of the GNU General Public License as published by # the +Free Software Foundation; either version 3 of the License, or # (at +your option) any later version. +# +# This program is distributed in the hope that it will be useful, # but +WITHOUT ANY WARRANTY; without even the implied warranty of # +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU +General Public License for more details. +# +# You should have received a copy of the GNU General Public License # +along with this program. If not, see <http://www.gnu.org/licenses/>. + +# Testing handle setup together with boundary violation signals. +# +# Some states are not allowed as reported on the manual, as noprint # +implies nostop, but nostop might print. +# +# Caveat: Setting the handle to nopass, ends up in a endless loop. + +if { ![istarget i?86-*-*] && ![istarget x86_64-*-* ] } { + verbose "Skipping x86 MPX tests." + return +} + +standard_testfile + +set comp_flags "-mmpx -fcheck-pointer-bounds -I${srcdir}/../nat/" + +if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} \ +[list debug nowarnings additional_flags=${comp_flags}]] } { + return -1 +} + +if ![runto_main] { + untested "could not run to main" + return -1 +} + +send_gdb "print have_mpx ()\r" +gdb_expect { + -re ".. = 1\r\n$gdb_prompt " { + pass "check whether processor supports MPX" + } + -re ".. = 0\r\n$gdb_prompt " { + verbose "processor does not support MPX; skipping MPX tests" + return + } +} + +set segv_bound_with_prompt ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$gdb_prompt $" + +set segv_bound_with_exit ".*Program received signal SIGSEGV,\ + Segmentation fault\r\nupper bound violation - bounds \\\{lbound\ + = 0x\[0-9a-fA-F\]+, ubound = 0x\[0-9a-fA-F\]+\\\} accessing\ + 0x\[0-9a-fA-F\]+.*$inferior_exited_re.*" + +# Using the handler for SIGSEGV as "print pass stop" +set parameters "print pass stop" +runto_main +send_gdb "handle SIGSEGV $parameters\n" +send_gdb "continue\n" + +gdb_expect { + -re $segv_bound_with_prompt { + pass $parameters + } +} +gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "should be in upper; $parameters" + +# Using the handler for SIGSEGV as "print pass nostop" +set parameters "print pass nostop" +runto_main + +gdb_test "handle SIGSEGV $parameters" "" "Setting\ the handler for +segfault 0" + +gdb_test_multiple "continue" "test 0" { + -re $segv_bound_with_exit { + pass $parameters + } + -re "$gdb_prompt $" { + fail $parameters + } +} + +gdb_test "where" "No stack." "no inferior $parameters" + +# Using the handler for SIGSEGV as "print nopass stop" +set parameters "print nopass stop" + +runto_main +gdb_test "handle SIGSEGV $parameters" "" "Setting\ the handler for +segfault 1" + +gdb_test_multiple "continue" "test 1" { + -re $segv_bound_with_prompt { + pass $parameters + } +} + +gdb_test "where" ".*#0 0x\[0-9a-fA-F\]+ in upper.*"\ + "should be in upper $parameters" + +# print nopass stop +set parameters "noprint pass nostop" +runto_main + +gdb_test "handle SIGSEGV $parameters" "" "Setting\ the handler for +segfault 2" + +gdb_test_multiple "continue" "test 2" { + -re "Continuing\..*$inferior_exited_re.*" { + pass $parameters + } +} + +gdb_test "where" "No stack." "no inferior $parameters" -- 2.1.4 Intel Deutschland GmbH Registered Address: Am Campeon 10-12, 85579 Neubiberg, Germany Tel: +49 89 99 8853-0, www.intel.de Managing Directors: Christin Eisenschmid, Christian Lamprechter Chairperson of the Supervisory Board: Nicole Lau Registered Office: Munich Commercial Register: Amtsgericht Muenchen HRB 186928 ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2015-12-18 13:44 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2015-12-18 13:44 [PATCH V2 1/2] Bound violation handling preparation Walfred Tedeschi 2015-12-18 13:44 ` [PATCH V2 2/2] Bound violation handling Walfred Tedeschi -- strict thread matches above, loose matches on Subject: below -- 2015-12-17 17:06 [PATCH V2 1/2] Bound violation handling preparation Walfred Tedeschi 2015-12-17 17:06 ` [PATCH V2 2/2] Bound violation handling Walfred Tedeschi 2015-12-17 17:12 ` Tedeschi, Walfred
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