Commit f3494345 authored by Chao Yu's avatar Chao Yu Committed by Jaegeuk Kim
Browse files

f2fs: fix potential use-after-free issue 



In error path of f2fs_read_multi_pages(), it should let last referrer
release decompress io context memory, otherwise, other referrer will
cause use-after-free issue.

Fixes: 4c8ff709 ("f2fs: support data compression")
Signed-off-by: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 03382f1a

fs/f2fs/data.c

+4 −4
Original line number Diff line number Diff line
@@ -2208,16 +2208,16 @@ int f2fs_read_multi_pages(struct compress_ctx *cc, struct bio **bio_ret, 
					page->index, for_write);

			if (IS_ERR(bio)) {

				ret = PTR_ERR(bio);

				bio = NULL;

				dic->failed = true;

				if (refcount_sub_and_test(dic->nr_cpages - i,

							&dic->ref))

							&dic->ref)) {

					f2fs_decompress_end_io(dic->rpages,

							cc->cluster_size, true,

							false);

					f2fs_free_dic(dic);

				}

				f2fs_put_dnode(&dn);

				*bio_ret = bio;

				*bio_ret = NULL;

				return ret;

			}

		}