| Message ID | 20220414211811.405F0C385A5@smtp.kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | + kasan-prevent-cpu_quarantine-corruption-when-cpu-offline-and-cache-shrink-occur-at-same-time.patch added to -mm tree | expand |
--- a/mm/kasan/quarantine.c~kasan-prevent-cpu_quarantine-corruption-when-cpu-offline-and-cache-shrink-occur-at-same-time +++ a/mm/kasan/quarantine.c @@ -315,6 +315,8 @@ static void per_cpu_remove_cache(void *a struct qlist_head *q; q = this_cpu_ptr(&cpu_quarantine); + if (READ_ONCE(q->offline)) + return; qlist_move_cache(q, &to_free, cache); qlist_free_all(&to_free, cache); }
The patch titled Subject: kasan: prevent cpu_quarantine corruption when CPU offline and cache shrink occur at same time has been added to the -mm tree. Its filename is kasan-prevent-cpu_quarantine-corruption-when-cpu-offline-and-cache-shrink-occur-at-same-time.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/kasan-prevent-cpu_quarantine-corruption-when-cpu-offline-and-cache-shrink-occur-at-same-time.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/kasan-prevent-cpu_quarantine-corruption-when-cpu-offline-and-cache-shrink-occur-at-same-time.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: Zqiang <qiang1.zhang@intel.com> Subject: kasan: prevent cpu_quarantine corruption when CPU offline and cache shrink occur at same time kasan_quarantine_remove_cache() is called in kmem_cache_shrink()/ destroy(). The kasan_quarantine_remove_cache() call is protected by cpuslock in kmem_cache_destroy() to ensure serialization with kasan_cpu_offline(). However the kasan_quarantine_remove_cache() call is not protected by cpuslock in kmem_cache_shrink(). When a CPU is going offline and cache shrink occurs at same time, the cpu_quarantine may be corrupted by interrupt (per_cpu_remove_cache operation). So add a cpu_quarantine offline flags check in per_cpu_remove_cache(). Link: https://lkml.kernel.org/r/20220414025925.2423818-1-qiang1.zhang@intel.com Signed-off-by: Zqiang <qiang1.zhang@intel.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> ---