diff options
| author | Vasily Gorbik <gor@linux.ibm.com> | 2026-03-22 03:35:10 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2026-03-23 07:58:32 -0600 |
| commit | 67807fbaf12719fca46a622d759484652b79c7c3 (patch) | |
| tree | f85bf87728fc6e080f30caeaa6020f3ef5899c3e | |
| parent | 24d4c90286b9a36a2b72d1e0ceeae237d427f975 (diff) | |
block: fix bio_alloc_bioset slowpath GFP handling
bio_alloc_bioset() first strips __GFP_DIRECT_RECLAIM from the optimistic
fast allocation attempt with try_alloc_gfp(). If that fast path fails,
the slowpath checks saved_gfp to decide whether blocking allocation is
allowed, but then still calls mempool_alloc() with the stripped gfp mask.
That can lead to a NULL bio pointer being passed into bio_init().
Fix the slowpath by using saved_gfp for the bio and bvec mempool
allocations.
Fixes: b520c4eef83d ("block: split bio_alloc_bioset more clearly into a fast and slowpath")
Reported-by: syzbot+09ddb593eea76a158f42@syzkaller.appspotmail.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/p01.gc6e9ad5845ad.ttca29g@ub.hpns
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/bio.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/block/bio.c b/block/bio.c index 5057047194c4..77067fa346d3 100644 --- a/block/bio.c +++ b/block/bio.c @@ -581,11 +581,11 @@ struct bio *bio_alloc_bioset(struct block_device *bdev, unsigned short nr_vecs, */ opf &= ~REQ_ALLOC_CACHE; - p = mempool_alloc(&bs->bio_pool, gfp); + p = mempool_alloc(&bs->bio_pool, saved_gfp); bio = p + bs->front_pad; if (nr_vecs > BIO_INLINE_VECS) { nr_vecs = BIO_MAX_VECS; - bvecs = mempool_alloc(&bs->bvec_pool, gfp); + bvecs = mempool_alloc(&bs->bvec_pool, saved_gfp); } } |