When the stack is corrupted (e.g., by the stack protector test),
collecting a backtrace during malloc causes a crash because the
backtrace code walks the invalid stack frames.
Update __stack_chk_fail() to set the flag before calling panic()
Also update stackprot_test() to set the flag before intentionally
corrupting the stack. This is needed because of the printf() in the
test: on sandbox printf() results in truetype allocations due to the
console output.
These fixes allow the stack protector test to pass with mcheck enabled.
Co-developed-by: Claude <noreply@anthropic.com>
Signed-off-by: Simon Glass <simon.glass@canonical.com>
a527909208