4.19-stable review patch. If anyone has any objections, please let me know.
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From: Edward Adam Davis eadavis@qq.com
[ Upstream commit d64ff0d2306713ff084d4b09f84ed1a8c75ecc32 ]
syzbot report a out of bounds in dbSplit, it because dmt_leafidx greater than num leaves per dmap tree, add a checking for dmt_leafidx in dbFindLeaf.
Shaggy: Modified sanity check to apply to control pages as well as leaf pages.
Reported-and-tested-by: syzbot+dca05492eff41f604890@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=dca05492eff41f604890 Signed-off-by: Edward Adam Davis eadavis@qq.com Signed-off-by: Dave Kleikamp dave.kleikamp@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/jfs/jfs_dmap.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c index 9f731847ae634..21597e8b727c6 100644 --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -3019,9 +3019,10 @@ static void dbAdjTree(dmtree_t *tp, int leafno, int newval, bool is_ctl) static int dbFindLeaf(dmtree_t *tp, int l2nb, int *leafidx, bool is_ctl) { int ti, n = 0, k, x = 0; - int max_size; + int max_size, max_idx;
max_size = is_ctl ? CTLTREESIZE : TREESIZE; + max_idx = is_ctl ? LPERCTL : LPERDMAP;
/* first check the root of the tree to see if there is * sufficient free space. @@ -3053,6 +3054,8 @@ static int dbFindLeaf(dmtree_t *tp, int l2nb, int *leafidx, bool is_ctl) */ assert(n < 4); } + if (le32_to_cpu(tp->dmt_leafidx) >= max_idx) + return -ENOSPC;
/* set the return to the leftmost leaf describing sufficient * free space.