linux/tools/objtool
Artem Savkov 22566c1603 objtool: Fix segfault in .cold detection with -ffunction-sections
Because find_symbol_by_name() traverses the same lists as
read_symbols(), changing sym->name in place without copying it affects
the result of find_symbol_by_name().  In the case where a ".cold"
function precedes its parent in sec->symbol_list, it can result in a
function being considered a parent of itself. This leads to function
length being set to 0 and other consequent side-effects including a
segfault in add_switch_table().  The effects of this bug are only
visible when building with -ffunction-sections in KCFLAGS.

Fix by copying the search string instead of modifying it in place.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 13810435b9 ("objtool: Support GCC 8's cold subfunctions")
Link: http://lkml.kernel.org/r/910abd6b5a4945130fd44f787c24e07b9e07c8da.1542736240.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-20 18:59:00 +01:00
..
arch/x86
Documentation
.gitignore
arch.h
Build
builtin-check.c
builtin-orc.c
builtin.h
cfi.h
check.c
check.h
elf.c objtool: Fix segfault in .cold detection with -ffunction-sections 2018-11-20 18:59:00 +01:00
elf.h
Makefile
objtool.c
orc_dump.c
orc_gen.c
orc.h
special.c
special.h
sync-check.sh
warn.h