From: Ghanshyam Agrawal <ghanshyam1898@xxxxxxxxx> [ Upstream commit a5f5e4698f8abbb25fe4959814093fb5bfa1aa9d ] When dmt_budmin is less than zero, it causes errors in the later stages. Added a check to return an error beforehand in dbAllocCtl itself. Reported-by: syzbot+b5ca8a249162c4b9a7d0@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=b5ca8a249162c4b9a7d0 Signed-off-by: Ghanshyam Agrawal <ghanshyam1898@xxxxxxxxx> Signed-off-by: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/jfs/jfs_dmap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c index 3ab410059dc20..39957361a7eed 100644 --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -1820,6 +1820,9 @@ dbAllocCtl(struct bmap * bmp, s64 nblocks, int l2nb, s64 blkno, s64 * results) return -EIO; dp = (struct dmap *) mp->data; + if (dp->tree.budmin < 0) + return -EIO; + /* try to allocate the blocks. */ rc = dbAllocDmapLev(bmp, dp, (int) nblocks, l2nb, results); -- 2.43.0