From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id 5HaGNLJ2qV/WbwAAWB0awg (envelope-from ) for ; Mon, 09 Nov 2020 12:04:50 -0500 Received: by simark.ca (Postfix, from userid 112) id CAF801F08B; Mon, 9 Nov 2020 12:04:50 -0500 (EST) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id 81E7E1E552 for ; Mon, 9 Nov 2020 12:04:49 -0500 (EST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id CCAB0386185A; Mon, 9 Nov 2020 17:04:48 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org CCAB0386185A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1604941488; bh=DnUwap9gFqSkhlkjDh5WM5xdwqqpXbygizfHbcYyK0U=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=TQEkJExVk6Xp8+e7g7yDzQux8xdvqzTecCJEAihrefGuSsOwHveIYqXM+S17FbcPA 0GClAJU9AWpN8TmfmqaKIuCYD7NvjJCh1hvpmO0i6ne4slJij2qB4Rkp8geiLUVGK4 JAKoke2pt/VPVdWvE891JnBc3ZFAgwP3xiK+wIMo= Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by sourceware.org (Postfix) with ESMTPS id 0E861385EC57 for ; Mon, 9 Nov 2020 17:04:46 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 0E861385EC57 Received: by mail-qt1-x841.google.com with SMTP id 7so2092039qtp.1 for ; Mon, 09 Nov 2020 09:04:46 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=DnUwap9gFqSkhlkjDh5WM5xdwqqpXbygizfHbcYyK0U=; b=rLGTM7q7NU0lGQZ0WuqxKRCsHoXvs4RDbXtQFCrkL/AfRbpXENBEqf/KCl0JY3uDh/ qqtOX4FXHAnO0VMET0BQ7T0J+DmjGMbXcvPH7/XfYftdfa+YDccr3oKxW99n4E1IuA5c sigwar2ylIgi3bLPmHX2toMc7NQgVdblaJG92MSVQ7DBazLX+E32fWbR33Ps6xkD5/U+ E9MFetPH+82+V5Rb2fC4MSzAD52KGUkKtRyZCKu0YAAzEJsVno6/mlCHpMwUu7/tPaf8 QCMKKQU5LT4PJrAdLF47ABpHjl59XGLUFwFMvMapkYQWBchB+uRcQ0KtWn3k7ohtRE2a aaaQ== X-Gm-Message-State: AOAM530vV8RnVuT5lx6QWgcvPS5D/igqmb7aPBA0LkW6l/aFm7GdudD1 +kxfF25MoeCnnZGcR31I69adW7aSkswDKw== X-Google-Smtp-Source: ABdhPJxLkaq6fKKAPyj2PgVG0reQLx9IcJGfEvI5rOH/SqJUT1Fik6YbeORGyuRY110t5Katthsbvw== X-Received: by 2002:ac8:16e9:: with SMTP id y38mr14461520qtk.261.1604941485036; Mon, 09 Nov 2020 09:04:45 -0800 (PST) Received: from localhost.localdomain ([2804:7f0:8284:1487:5c3b:b268:ad95:5f37]) by smtp.gmail.com with ESMTPSA id s2sm5948358qtw.44.2020.11.09.09.04.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Nov 2020 09:04:44 -0800 (PST) To: gdb-patches@sourceware.org Subject: [PATCH v3 01/24] New target methods for memory tagging support Date: Mon, 9 Nov 2020 14:04:12 -0300 Message-Id: <20201109170435.15766-2-luis.machado@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201109170435.15766-1-luis.machado@linaro.org> References: <20201109170435.15766-1-luis.machado@linaro.org> X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Luis Machado via Gdb-patches Reply-To: Luis Machado Cc: david.spickett@linaro.org Errors-To: gdb-patches-bounces@sourceware.org Sender: "Gdb-patches" Updates on v3: - Updated the code documentation for the fetch_memtags and store_memtags methods. Updates on v2: - Added type parameter to fetch_memtags/store_memtags hooks. -- This patch starts adding some of the generic pieces to accomodate memory tagging. We have three new target methods: - supports_memory_tagging: Checks if the target supports memory tagging. This defaults to false for targets that don't support memory tagging. - fetch_memtags: Fetches the allocation tags associated with a particular memory range [address, address + length). The default is to return 0 without returning any tags. This should only be called if memory tagging is supported. - store_memtags: Stores a set of allocation tags for a particular memory range [address, address + length). The default is to return 0. This should only be called if memory tagging is supported. It also adds a control option for enabling/disabling memory tagging manually: set memory-tagging on/off. The default is "on", with GDB making its use conditional to the architecture supporting memory tagging. gdb/ChangeLog: YYYY-MM-DD Luis Machado * printcmd.c (memtag): New static global. (show_memtag): New function. (_initialize_printcmd): Add set/show memory-tagging command. * remote.c (remote_target) : New method override. : New method override. : New method override. (remote_target::supports_memory_tagging): New method. (remote_target::fetch_memtags): New method. (remote_target::store_memtags): New method. * target-delegates.c (dummy_target) : New method override. : New method override. : New method override. (debug_target) : New method override. : New method override. : New method override. (target_ops::supports_memory_tagging): New method. (target_ops::fetch_memtags): New method. (target_ops::store_memtags): New method. (dummy_target::supports_memory_tagging): New method. (dummy_target::fetch_memtags): New method. (dummy_target::store_memtags): New method. (debug_target::supports_memory_tagging): New method. (debug_target::fetch_memtags): New method. (debug_target::store_memtags): New method. * target.h (struct target_ops) : New virtual method. : New virtual method. : New virtual method. (target_supports_memory_tagging): Define. (target_fetch_memtags): Define. (target_store_memtags): Define. --- gdb/printcmd.c | 28 ++++++++++++++ gdb/remote.c | 36 ++++++++++++++++++ gdb/target-delegates.c | 84 ++++++++++++++++++++++++++++++++++++++++++ gdb/target.h | 37 +++++++++++++++++++ 4 files changed, 185 insertions(+) diff --git a/gdb/printcmd.c b/gdb/printcmd.c index f7186c296a..28451612ab 100644 --- a/gdb/printcmd.c +++ b/gdb/printcmd.c @@ -84,6 +84,24 @@ static CORE_ADDR last_examine_address; static value_ref_ptr last_examine_value; +/* If TRUE (default), and the architecture supports it, GDB will attempt to use + the memory tagging infrastructure to validate certain memory accesses. It + will also report memory tag violations alongside a SIGSEGV signal. + + If FALSE, GDB will not use memory tagging in any way, and debugging will work + in the standard way. */ +static bool memtag = true; + +static void +show_memtag (struct ui_file *file, int from_tty, + struct cmd_list_element *c, + const char *value) +{ + fprintf_filtered (file, + _("Use of memory tagging infrastructure is \"%s\".\n"), + value); +} + /* Largest offset between a symbolic value and an address, that will be printed as `0x1234 '. */ @@ -2893,4 +2911,14 @@ Construct a GDB command and then evaluate it.\n\ Usage: eval \"format string\", ARG1, ARG2, ARG3, ..., ARGN\n\ Convert the arguments to a string as \"printf\" would, but then\n\ treat this string as a command line, and evaluate it.")); + + add_setshow_boolean_cmd ("memory-tagging", class_support, + &memtag, _("\ +Set whether the debugger should use memory tagging infrastructure."), _("\ +Show whether the debugger should use memory tagging infrastructure."), _("\ +If on, gdb will attempt to validate memory tags and will warn the user if\n\ +certain operations have illegal tags."), + NULL, + show_memtag, + &setlist, &showlist); } diff --git a/gdb/remote.c b/gdb/remote.c index 71f814efb3..2686de3501 100644 --- a/gdb/remote.c +++ b/gdb/remote.c @@ -686,6 +686,16 @@ class remote_target : public process_stratum_target int remove_exec_catchpoint (int) override; enum exec_direction_kind execution_direction () override; + bool supports_memory_tagging () override; + + /* Read memory tags via the qMemTags packet */ + int fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags, int type) override; + + /* Write allocation tags via the QMemTags packet. */ + int store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags, int type) override; + public: /* Remote specific methods. */ void remote_download_command_source (int num, ULONGEST addr, @@ -14389,6 +14399,32 @@ set_range_stepping (const char *ignore_args, int from_tty, } } +/* Implement the "supports_memory_tagging" target_ops method. */ + +bool +remote_target::supports_memory_tagging () +{ + return false; +} + +/* Implement the "fetch_memtags" target_ops method. */ + +int +remote_target::fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags, int type) +{ + return 0; +} + +/* Implement the "store_memtags" target_ops method. */ + +int +remote_target::store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags, int type) +{ + return 0; +} + void _initialize_remote (); void _initialize_remote () diff --git a/gdb/target-delegates.c b/gdb/target-delegates.c index 437b19b858..fbebc8b4ce 100644 --- a/gdb/target-delegates.c +++ b/gdb/target-delegates.c @@ -173,6 +173,11 @@ struct dummy_target : public target_ops const struct frame_unwind *get_tailcall_unwinder () override; void prepare_to_generate_core () override; void done_generating_core () override; + bool supports_memory_tagging () override; + int fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags, int type) override; + int store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags, int type) override; }; struct debug_target : public target_ops @@ -344,6 +349,11 @@ struct debug_target : public target_ops const struct frame_unwind *get_tailcall_unwinder () override; void prepare_to_generate_core () override; void done_generating_core () override; + bool supports_memory_tagging () override; + int fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags, int type) override; + int store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags, int type) override; }; void @@ -4413,3 +4423,77 @@ debug_target::done_generating_core () fputs_unfiltered (")\n", gdb_stdlog); } +bool +target_ops::supports_memory_tagging () +{ + return this->beneath ()->supports_memory_tagging (); +} + +int +target_ops::fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags, int type) +{ + return this->beneath ()->fetch_memtags (address, len, tags, type); +} + +int +target_ops::store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags, int type) +{ + return this->beneath ()->store_memtags (address, len, tags, type); +} + +bool +dummy_target::supports_memory_tagging () +{ + return false; +} + +int +dummy_target::fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags, int type) +{ + return 0; +} + +int +dummy_target::store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags, int type) +{ + return 0; +} + +bool +debug_target::supports_memory_tagging () +{ + bool result; + fprintf_unfiltered (gdb_stdlog, "-> %s->supports_memory_tagging (...)\n", this->beneath ()->shortname ()); + result = this->beneath ()->supports_memory_tagging (); + fprintf_unfiltered (gdb_stdlog, "<- %s->supports_memory_tagging (", this->beneath ()->shortname ()); + fputs_unfiltered (") = ", gdb_stdlog); + target_debug_print_bool (result); + fputs_unfiltered ("\n", gdb_stdlog); + return result; +} + +int +debug_target::fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags, int type) +{ + fprintf_unfiltered (gdb_stdlog, "-> %s->fetch_memtags (...)\n", this->beneath ()->shortname ()); + int result = this->beneath ()->fetch_memtags (address, len, tags, type); + fprintf_unfiltered (gdb_stdlog, "<- %s->fetch_memtags (", this->beneath ()->shortname ()); + fputs_unfiltered (")\n", gdb_stdlog); + return result; +} + +int +debug_target::store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags, int type) +{ + fprintf_unfiltered (gdb_stdlog, "-> %s->store_memtags (...)\n", this->beneath ()->shortname ()); + int result = this->beneath ()->store_memtags (address, len, tags, type); + fprintf_unfiltered (gdb_stdlog, "<- %s->store_memtags (", this->beneath ()->shortname ()); + fputs_unfiltered (")\n", gdb_stdlog); + return result; +} diff --git a/gdb/target.h b/gdb/target.h index 416b8089fa..3bc958a406 100644 --- a/gdb/target.h +++ b/gdb/target.h @@ -1260,6 +1260,34 @@ struct target_ops /* Cleanup after generating a core file. */ virtual void done_generating_core () TARGET_DEFAULT_IGNORE (); + + /* Returns true if the target supports memory tagging. */ + virtual bool supports_memory_tagging () + TARGET_DEFAULT_RETURN (false); + + /* Return the allocated memory tags of type TYPE associated with + [ADDRESS, ADDRESS + LEN) in TAGS. + + LEN is the number of bytes in the memory range. TAGS is a vector of + bytes containing the tags found in the above memory range. + + It is up to the architecture/target to interpret the bytes in the TAGS + vector and read the tags appropriately. */ + virtual int fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags, int type) + TARGET_DEFAULT_IGNORE (); + + /* Write the allocation tags of type TYPE contained in TAGS to the memory + range [ADDRESS, ADDRESS + LEN). + + LEN is the number of bytes in the memory range. TAGS is a vector of + bytes containing the tags to be stored to the memory range. + + It is up to the architecture/target to interpret the bytes in the TAGS + vector and store them appropriately. */ + virtual int store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags, int type) + TARGET_DEFAULT_IGNORE (); }; /* Deleter for std::unique_ptr. See comments in @@ -2312,6 +2340,15 @@ extern gdb::unique_xmalloc_ptr target_fileio_read_stralloc #define target_augmented_libraries_svr4_read() \ (current_top_target ()->augmented_libraries_svr4_read) () +#define target_supports_memory_tagging() \ + ((current_top_target ()->supports_memory_tagging) ()) + +#define target_fetch_memtags(address, len, tags, type) \ + (current_top_target ()->fetch_memtags) ((address), (len), (tags), (type)) + +#define target_store_memtags(address, len, tags, type) \ + (current_top_target ()->store_memtags) ((address), (len), (tags), (type)) + /* Command logging facility. */ #define target_log_command(p) \ -- 2.17.1