From: Andrey Konovalov andreyknvl@google.com
mainline inclusion from mainline-v5.12-rc7 commit 06b1f85588948bd4c772845e5d6891b8f6082248 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I49LY9 CVE: NA
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When page poisoning is enabled, it accesses memory that is marked as poisoned by KASAN, which leas to false-positive KASAN reports.
Suppress the reports by adding KASAN annotations to unpoison_page() (poison_page() already has them).
Link: https://lkml.kernel.org/r/2dc799014d31ac13fd97bd906bad33e16376fc67.161711850... Signed-off-by: Andrey Konovalov andreyknvl@google.com Cc: Alexander Potapenko glider@google.com Cc: Marco Elver elver@google.com Cc: Dmitry Vyukov dvyukov@google.com Cc: Andrey Ryabinin aryabinin@virtuozzo.com Cc: Andrey Konovalov andreyknvl@gmail.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org (cherry picked from commit 06b1f85588948bd4c772845e5d6891b8f6082248) Signed-off-by: Yuanzheng Song songyuanzheng@huawei.com Reviewed-by: Kefeng Wang wangkefeng.wang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- mm/page_poison.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/mm/page_poison.c b/mm/page_poison.c index ae0482cded87..a08423cb11ca 100644 --- a/mm/page_poison.c +++ b/mm/page_poison.c @@ -108,12 +108,14 @@ static void unpoison_page(struct page *page) void *addr;
addr = kmap_atomic(page); + kasan_disable_current(); /* * Page poisoning when enabled poisons each and every page * that is freed to buddy. Thus no extra check is done to * see if a page was poisoned. */ - check_poison_mem(addr, PAGE_SIZE); + check_poison_mem(kasan_reset_tag(addr), PAGE_SIZE); + kasan_enable_current(); kunmap_atomic(addr); }