Re: [RFC][PATCH 4/5] shmem: Avoid segfault in shmem_read_mapping_page_gfp()
From: Ajay Garg <hidden>
Date: 2021-11-12 12:53:58
Also in:
linux-fscrypt, linux-fsdevel, linux-integrity, linux-mm, lkml
Hi Roberto. Identical patch has been floated earlier via : https://lore.kernel.org/linux-mm/CAMZfGtUp6dkT4OWzLhL8whqNnXAbfVw5c6AQogHzY3bbM_k2Qw@mail.gmail.com/T/#m2189d135b9293de9b4a11362f0179c17b254d5ab (local) Thanks and Regards, Ajay On Fri, Nov 12, 2021 at 6:15 PM Roberto Sassu [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Check the hwpoison page flag only if the page is valid in shmem_read_mapping_page_gfp(). The PageHWPoison() macro tries to access the page flags and cannot work on an error pointer. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> --- mm/shmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/mm/shmem.c b/mm/shmem.c index 23c91a8beb78..427863cbf0dc 100644 --- a/mm/shmem.c +++ b/mm/shmem.c@@ -4222,7 +4222,7 @@ struct page *shmem_read_mapping_page_gfp(struct address_space *mapping, else unlock_page(page); - if (PageHWPoison(page)) + if (!IS_ERR(page) && PageHWPoison(page)) page = ERR_PTR(-EIO); return page; --2.32.0