From: Daeho Jeong <[email protected]>
By Colin's static analysis, we found out there is a null page reference
under low memory situation in redirty_blocks. I've made the page finding
loop stop immediately and return an error not to cause further memory
pressure when we run into a failure to find a page under low memory
condition.
Signed-off-by: Daeho Jeong <[email protected]>
Reported-by: Colin Ian King <[email protected]>
Fixes: 5fdb322ff2c2 ("f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE")
---
v2: changed error value and quit the page finding loop immediately
when error occurs
---
fs/f2fs/file.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 9e5275716be8..d27173c24391 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -4060,8 +4060,10 @@ static int redirty_blocks(struct inode *inode, pgoff_t page_idx, int len)
for (i = 0; i < page_len; i++, redirty_idx++) {
page = find_lock_page(mapping, redirty_idx);
- if (!page)
- ret = -ENOENT;
+ if (!page) {
+ ret = -ENOMEM;
+ break;
+ }
set_page_dirty(page);
f2fs_put_page(page, 1);
f2fs_put_page(page, 0);
--
2.29.2.729.g45daf8777d-goog