diff options
Diffstat (limited to 'gdb/i386-linux-tdep.c')
| -rw-r--r-- | gdb/i386-linux-tdep.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c index af39e78..63cda45 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 +385,71 @@ i386_canonicalize_syscall (int syscall) return gdb_sys_no_syscall; } +/* Value of the sigcode in case of a boundary fault. */ + +#define SIG_CODE_BONDARY_FAULT 3 + +/* i386 GNU/Linux implementation of the handle_segmentation_fault + gdbarch hook. Displays information related to MPX bound + violations. */ +void +i386_linux_handle_segmentation_fault (struct gdbarch *gdbarch, + struct ui_out *uiout) +{ + CORE_ADDR lower_bound, upper_bound, access; + int is_upper; + long sig_code = 0; + + if (!i386_mpx_enabled ()) + return; + + TRY + { + /* Sigcode evaluates if the actual segfault is a boundary violation. */ + sig_code = parse_and_eval_long ("$_siginfo.si_code\n"); + + lower_bound + = parse_and_eval_long ("$_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 + + /* If this is not a boundary violation just return. */ + if (sig_code != SIG_CODE_BONDARY_FAULT) + return; + + 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, _(" while accessing address ")); + ui_out_field_fmt (uiout, "bound-access", "%s", + paddress (gdbarch, access)); + + ui_out_text (uiout, _("\nBounds: [lower = ")); + ui_out_field_fmt (uiout, "lower-bound", "%s", + paddress (gdbarch, lower_bound)); + + ui_out_text (uiout, _(", upper = ")); + ui_out_field_fmt (uiout, "upper-bound", "%s", + paddress (gdbarch, upper_bound)); + + ui_out_text (uiout, _("]")); +} + /* 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 +1068,8 @@ i386_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) i386_linux_get_syscall_number); set_gdbarch_get_siginfo_type (gdbarch, x86_linux_get_siginfo_type); + set_gdbarch_handle_segmentation_fault (gdbarch, + i386_linux_handle_segmentation_fault); } /* Provide a prototype to silence -Wmissing-prototypes. */ |