The backtrace when a fortify check failed was not correct. This change
adds all of the necessary directives to get a correct backtrace.
Fix the strcmp directives and change all labels to local labels.
Testing:
- Verify that the runtime can decode the stack for __memcpy_chk, __memset_chk,
__strcpy_chk, __strcat_chk fortify failures.
- Verify that gdb can decode the stack properly when hitting a fortify check.
- Verify that the runtime can decode the stack for a seg fault for all of the
_chk functions and for memcpy/memset.
- Verify that gdb can decode the stack for a seg fault for all of the _chk
functions and for memcpy/memset.
- Verify that the runtime can decode the stack for a seg fault for strcmp.
- Verify that gdb can decode the stack for a seg fault in strcmp.
Bug: 10342460
Bug: 10345269
Merge from internal master.
(cherry-picked from 05332f2ce7)
Change-Id: Ibc919b117cfe72b9ae97e35bd48185477177c5ca
The libcorkscrew stack unwinder does not understand cfi directives,
so add .save directives so that it can function properly.
Also add the directives in to strcmp.S and fix a missing set of
directives in cortex-a9/memcpy_base.S.
Bug: 10345269
Merge from internal master.
(cherry-picked from 5f7ccea3ff)
Change-Id: If48a216203216a643807f5d61906015984987189
This change pulls the memcpy code out into a new file so that the
__strcpy_chk and __strcat_chk can use it with an include.
The new versions of the two chk functions uses assembly versions
of strlen and memcpy to implement this check. This allows near
parity with the assembly versions of strcpy/strcat. It also means that
as memcpy implementations get faster, so do the chk functions.
Other included changes:
- Change all of the assembly labels to local labels. The other labels
confuse gdb and mess up backtracing.
- Add .cfi_startproc and .cfi_endproc directives so that gdb is not
confused when falling through from one function to another.
- Change all functions to use cfi directives since they are more powerful.
- Move the memcpy_chk fail code outside of the memcpy function definition
so that backtraces work properly.
- Preserve lr before the calls to __fortify_chk_fail so that the backtrace
actually works.
Testing:
- Ran the bionic unit tests. Verified all error messages in logs are set
correctly.
- Ran libc_test, replacing strcpy with __strcpy_chk and replacing
strcat with __strcat_chk.
- Ran the debugger on nexus10, nexus4, and old nexus7. Verified that the
backtrace is correct for all fortify check failures. Also verify that
when falling through from __memcpy_chk to memcpy that the backtrace is
still correct. Also verified the same for __memset_chk and bzero.
Verified the two different paths in the cortex-a9 memset routine that
save variables to the stack still show the backtrace properly.
Bug: 9293744
(cherry-picked from 2be91915dc)
Change-Id: Ia407b74d3287d0b6af0139a90b6eb3bfaebf2155
