Under memory pressure, bio_alloc_bioset() may fail and return NULL. Add a check to prevent NULL pointer dereference in iomap_alloc_ioend(). This could happen when the system is under memory pressure and the allocation of the bio structure fails. Signed-off-by: Ye Chey <yechey@xxxxxxxxxxx> --- fs/iomap/buffered-io.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 5b08bd417..d243b191e 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -1618,6 +1618,8 @@ static struct iomap_ioend *iomap_alloc_ioend(struct iomap_writepage_ctx *wpc, bio = bio_alloc_bioset(wpc->iomap.bdev, BIO_MAX_VECS, REQ_OP_WRITE | wbc_to_write_flags(wbc), GFP_NOFS, &iomap_ioend_bioset); + if (!bio) + return NULL; bio->bi_iter.bi_sector = iomap_sector(&wpc->iomap, pos); bio->bi_end_io = iomap_writepage_end_bio; bio->bi_write_hint = inode->i_write_hint; -- 2.44.0
