Re: [PATCH] Restore behavior of disabling address randomization by default on GDBserver

Pedro Alves
2018-08-22T16:14:48Z

On 08/22/2018 05:05 PM, Simon Marchi wrote:
> Commit
>
> c12a508 ("Add client_state struct.")
>
> inadvertently changed the default behavior of GDBserver wrt address
> randomization. The old disable_randomization global variable was
> initialized to 1, whereas the corresponding field in the client_state
> structure is initialized to 0.
>
> This fixes
>
> make check TESTS="gdb.base/jit-simple.exp" RUNTESTFLAGS="--target_board=native-gdbserver"
> make check TESTS="gdb.base/execl-update-breakpoints.exp" RUNTESTFLAGS="--target_board=native-gdbserver"
>
> Note that the execl-update-breakpoints.exp would only fail on systems
> where the toolchain emits position-independent executables by default
> (otherwise the main executable position is never randomized, so the
> value of disable_randomization didn't matter).

Thanks for fixing this!

This is OK, but please double-check the patch/commit, since it
seems to include the same hunk twice. Kind of looks like
the fix diff made it to the commit log?

>
> gdb/gdbserver/ChangeLog:
>
> PR gdb/23374
> PR gdb/23375
> * server.h (struct client_state) <disable_randomization>:
> Initialize to 1.
>
> diff --git a/gdb/gdbserver/server.h b/gdb/gdbserver/server.h index
> 8e197ee..5e41e2f 100644 --- a/gdb/gdbserver/server.h +++
> b/gdb/gdbserver/server.h @@ -176,7 +176,7 @@ struct client_state
>
> /* Whether we should attempt to disable the operating system's address
> space randomization feature before starting an inferior. */
> - int disable_randomization = 0;
> + int disable_randomization = 1;
>
> int pass_signals[GDB_SIGNAL_LAST];
> int program_signals[GDB_SIGNAL_LAST];
> ---
> gdb/gdbserver/server.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/gdb/gdbserver/server.h b/gdb/gdbserver/server.h
> index 8e197ee..5e41e2f 100644
> --- a/gdb/gdbserver/server.h
> +++ b/gdb/gdbserver/server.h
> @@ -176,7 +176,7 @@ struct client_state
>
> /* Whether we should attempt to disable the operating system's address
> space randomization feature before starting an inferior. */
> - int disable_randomization = 0;
> + int disable_randomization = 1;
>
> int pass_signals[GDB_SIGNAL_LAST];
> int program_signals[GDB_SIGNAL_LAST];
>
Thanks,
Pedro Alves