The patch below does not apply to the 6.12-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y git checkout FETCH_HEAD git cherry-pick -x 7a19afee6fb39df63ddea7ce78976d8c521178c6 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025090612-washhouse-palpitate-525c@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7a19afee6fb39df63ddea7ce78976d8c521178c6 Mon Sep 17 00:00:00 2001 From: Yeoreum Yun yeoreum.yun@arm.com Date: Fri, 1 Aug 2025 13:02:36 +0100 Subject: [PATCH] kunit: kasan_test: disable fortify string checker on kasan_strings() test
Similar to commit 09c6304e38e4 ("kasan: test: fix compatibility with FORTIFY_SOURCE") the kernel is panicing in kasan_string().
This is due to the `src` and `ptr` not being hidden from the optimizer which would disable the runtime fortify string checker.
Call trace: __fortify_panic+0x10/0x20 (P) kasan_strings+0x980/0x9b0 kunit_try_run_case+0x68/0x190 kunit_generic_run_threadfn_adapter+0x34/0x68 kthread+0x1c4/0x228 ret_from_fork+0x10/0x20 Code: d503233f a9bf7bfd 910003fd 9424b243 (d4210000) ---[ end trace 0000000000000000 ]--- note: kunit_try_catch[128] exited with irqs disabled note: kunit_try_catch[128] exited with preempt_count 1 # kasan_strings: try faulted: last ** replaying previous printk message ** # kasan_strings: try faulted: last line seen mm/kasan/kasan_test_c.c:1600 # kasan_strings: internal error occurred preventing test case from running: -4
Link: https://lkml.kernel.org/r/20250801120236.2962642-1-yeoreum.yun@arm.com Fixes: 73228c7ecc5e ("KASAN: port KASAN Tests to KUnit") Signed-off-by: Yeoreum Yun yeoreum.yun@arm.com Cc: Alexander Potapenko glider@google.com Cc: Andrey Konovalov andreyknvl@gmail.com Cc: Andrey Ryabinin ryabinin.a.a@gmail.com Cc: Dmitriy Vyukov dvyukov@google.com Cc: Vincenzo Frascino vincenzo.frascino@arm.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org
diff --git a/mm/kasan/kasan_test_c.c b/mm/kasan/kasan_test_c.c index e0968acc03aa..f4b17984b627 100644 --- a/mm/kasan/kasan_test_c.c +++ b/mm/kasan/kasan_test_c.c @@ -1578,9 +1578,11 @@ static void kasan_strings(struct kunit *test)
ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + OPTIMIZER_HIDE_VAR(ptr);
src = kmalloc(KASAN_GRANULE_SIZE, GFP_KERNEL | __GFP_ZERO); strscpy(src, "f0cacc1a0000000", KASAN_GRANULE_SIZE); + OPTIMIZER_HIDE_VAR(src);
/* * Make sure that strscpy() does not trigger KASAN if it overreads into