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author | Luis Machado <luis.machado@linaro.org> | 2020-06-15 15:44:20 -0300 |
---|---|---|
committer | Luis Machado <luis.machado@linaro.org> | 2020-06-16 09:58:32 -0300 |
commit | a08d973656aceb94187d5d283bff2e042fe234b5 (patch) | |
tree | 623ecc9312cd4650475b3765ffc9aeeadf9d46b1 | |
parent | 9e45a8561d934bc1ae07ff4356312afb69e0bd00 (diff) | |
download | binutils-gdb-a08d973656aceb94187d5d283bff2e042fe234b5.tar.gz |
Report TAG violation error information
Whenever a memory tag violation occurs, we get a SIGSEGV. Additional
information can be obtained through the siginfo data structure.
For AArch64 the Linux kernel may expose the fault address and tag
information, if we have a synchronous event. Otherwise there is
not fault address available.
gdb/ChangeLog:
YYYY-MM-DD Luis Machado <luis.machado@linaro.org>
* aarch64-linux-tdep.c
(aarch64_linux_handle_segmentation_fault): New function.
(aarch64_linux_init_abi): Register
aarch64_linux_handle_segmentation_fault as segmentation fault hook.
* arch/aarch64-linux.h (SEGV_MTEAERR): Define.
(SEGV_MTESERR): Define.
-rw-r--r-- | gdb/aarch64-linux-tdep.c | 54 | ||||
-rw-r--r-- | gdb/arch/aarch64-linux.h | 6 |
2 files changed, 60 insertions, 0 deletions
diff --git a/gdb/aarch64-linux-tdep.c b/gdb/aarch64-linux-tdep.c index 6fee4437f23..66c8fa0ac5a 100644 --- a/gdb/aarch64-linux-tdep.c +++ b/gdb/aarch64-linux-tdep.c @@ -1700,6 +1700,57 @@ aarch64_linux_memtag_to_string (struct gdbarch *gdbarch, return string_printf ("0x%s", phex_nz (tag, sizeof (tag))); } +/* AArch64 Linux implementation of the handle_segmentation_fault gdbarch + hook. Displays information about possible memory tag violations. */ + +static void +aarch64_linux_handle_segmentation_fault (struct gdbarch *gdbarch, + struct ui_out *uiout) +{ + CORE_ADDR fault_addr = 0; + long si_code = 0; + CORE_ADDR ltag; + CORE_ADDR atag; + + try + { + /* Sigcode tells us if the segfault is actually a memory tag + violation. */ + si_code = parse_and_eval_long ("$_siginfo.si_code\n"); + + fault_addr + = parse_and_eval_long ("$_siginfo._sifields._sigfault.si_addr"); + } + catch (const gdb_exception &exception) + { + return; + } + + /* If this is not a memory tag violation, just return. */ + if (si_code != SEGV_MTEAERR && si_code != SEGV_MTESERR) + return; + + uiout->text ("\n"); + + uiout->field_string ("sigcode-meaning", _("Memory tag violation")); + uiout->text (_(" while accessing address ")); + uiout->field_core_addr ("fault-addr", gdbarch, fault_addr); + uiout->text ("\n"); + + uiout->text (_("Logical tag ")); + ltag = aarch64_linux_get_ltag (fault_addr); + uiout->field_core_addr ("logical-tag", gdbarch, ltag); + uiout->text ("\n"); + + if (aarch64_linux_get_atag (fault_addr, &atag) != 0) + uiout->text (_("Allocation tag unavailable")); + else + { + uiout->text (_("Allocation tag ")); + uiout->field_core_addr ("allocation-tag", gdbarch, atag); + } +} + static void aarch64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) { @@ -1780,6 +1831,9 @@ aarch64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) /* Register a hook for converting a memory tag to a string. */ set_gdbarch_memtag_to_string (gdbarch, aarch64_linux_memtag_to_string); + + set_gdbarch_handle_segmentation_fault (gdbarch, + aarch64_linux_handle_segmentation_fault); } /* Initialize the aarch64_linux_record_tdep. */ diff --git a/gdb/arch/aarch64-linux.h b/gdb/arch/aarch64-linux.h index 23cd98f1f30..3006b316fd5 100644 --- a/gdb/arch/aarch64-linux.h +++ b/gdb/arch/aarch64-linux.h @@ -35,6 +35,12 @@ #define MTE_LOGICAL_TAG_START_BIT 56 #define MTE_LOGICAL_MAX_VALUE 0xf +/* Memory tagging definitions. */ +#ifndef SEGV_MTEAERR +# define SEGV_MTEAERR 8 +# define SEGV_MTESERR 9 +#endif + /* Return the number of tag granules in the memory range [ADDR, ADDR + LEN) given GRANULE_SIZE. */ extern int get_tag_granules (CORE_ADDR addr, size_t len, |