From 72c774aa9d1e16bfd247096935e7dae194d84929 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 24 Mar 2025 14:56:07 -0700 Subject: objtool, panic: Disable SMAP in __stack_chk_fail() __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 Signed-off-by: Ingo Molnar Cc: Kees Cook Cc: Andrew Morton Cc: Linus Torvalds Link: https://lore.kernel.org/r/a3e97e0119e1b04c725a8aa05f7bc83d98e657eb.1742852847.git.jpoimboe@kernel.org --- kernel/panic.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'kernel') diff --git a/kernel/panic.c b/kernel/panic.c index d8635d5cecb2..f9f0c5148f6a 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); -- cgit v1.2.3