The patch titled
Subject: ubsan: check panic_on_warn
has been added to the -mm tree. Its filename is
ubsan-check-panic_on_warn.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/ubsan-check-panic_on_warn.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/ubsan-check-panic_on_warn.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Kees Cook <keescook@xxxxxxxxxxxx>
Subject: ubsan: check panic_on_warn
Syzkaller expects kernel warnings to panic when the panic_on_warn sysctl
is set. More work is needed here to have UBSan reuse the WARN
infrastructure, but for now, just check the flag manually.
Link: https://lore.kernel.org/lkml/CACT4Y+bsLJ-wFx_TaXqax3JByUOWB3uk787LsyMVcfW6JzzGvg@xxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20200227193516.32566-5-keescook@xxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Elena Petrova <lenaptr@xxxxxxxxxx>
Cc: "Gustavo A. R. Silva" <gustavo@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/ubsan.c | 11 +++++++++++
1 file changed, 11 insertions(+)
--- a/lib/ubsan.c~ubsan-check-panic_on_warn
+++ a/lib/ubsan.c
@@ -156,6 +156,17 @@ static void ubsan_epilogue(void)
"========================================\n");
current->in_ubsan--;
+
+ if (panic_on_warn) {
+ /*
+ * This thread may hit another WARN() in the panic path.
+ * Resetting this prevents additional WARN() from panicking the
+ * system on this thread. Other threads are blocked by the
+ * panic_mutex in panic().
+ */
+ panic_on_warn = 0;
+ panic("panic_on_warn set ...\n");
+ }
}
static void handle_overflow(struct overflow_data *data, void *lhs,
_
Patches currently in -mm which might be from keescook@xxxxxxxxxxxx are
shmem-distribute-switch-variables-for-initialization.patch
lib-test_stackinitc-xfail-switch-variable-init-tests.patch
ubsan-add-trap-instrumentation-option.patch
ubsan-split-bounds-checker-from-other-options.patch
lkdtm-bugs-add-arithmetic-overflow-and-array-bounds-checks.patch
ubsan-check-panic_on_warn.patch
kasan-unset-panic_on_warn-before-calling-panic.patch
ubsan-include-bug-type-in-report-header.patch
