From: Josh Poimboeuf jpoimboe@kernel.org
[ Upstream commit 72c774aa9d1e16bfd247096935e7dae194d84929 ]
__stack_chk_fail() can be called from uaccess-enabled code. Make sure uaccess gets disabled before calling panic().
Fixes the following warning:
kernel/trace/trace_branch.o: error: objtool: ftrace_likely_update+0x1ea: call to __stack_chk_fail() with UACCESS enabled
Signed-off-by: Josh Poimboeuf jpoimboe@kernel.org Signed-off-by: Ingo Molnar mingo@kernel.org Cc: Kees Cook keescook@chromium.org Cc: Andrew Morton akpm@linux-foundation.org Cc: Linus Torvalds torvalds@linux-foundation.org Link: https://lore.kernel.org/r/a3e97e0119e1b04c725a8aa05f7bc83d98e657eb.174285284... Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/panic.c | 6 ++++++ tools/objtool/check.c | 5 ++++- 2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/kernel/panic.c b/kernel/panic.c index fbc59b3b64d0b..ddad0578355bb 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -832,9 +832,15 @@ device_initcall(register_warn_debugfs); */ __visible noinstr void __stack_chk_fail(void) { + unsigned long flags; + instrumentation_begin(); + flags = user_access_save(); + panic("stack-protector: Kernel stack is corrupted in: %pB", __builtin_return_address(0)); + + user_access_restore(flags); instrumentation_end(); } EXPORT_SYMBOL(__stack_chk_fail); diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 5b0ff4b9221d7..b84175ccd6107 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1242,12 +1242,15 @@ static const char *uaccess_safe_builtin[] = { "__ubsan_handle_load_invalid_value", /* STACKLEAK */ "stackleak_track_stack", + /* TRACE_BRANCH_PROFILING */ + "ftrace_likely_update", + /* STACKPROTECTOR */ + "__stack_chk_fail", /* misc */ "csum_partial_copy_generic", "copy_mc_fragile", "copy_mc_fragile_handle_tail", "copy_mc_enhanced_fast_string", - "ftrace_likely_update", /* CONFIG_TRACE_BRANCH_PROFILING */ "rep_stos_alternative", "rep_movs_alternative", "__copy_user_nocache",