From: Edward Adam Davis <eadavis@qq.com> stable inclusion from stable-v6.6.55 commit 7fff9a9f866e99931cf6fa260288e55d01626582 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYRAK CVE: CVE-2024-49902 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ 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> Signed-off-by: Yifan Qiao <qiaoyifan4@huawei.com> --- 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 5713994328cb..7e8fa0c56a3d 100644 --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -2944,9 +2944,10 @@ 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. @@ -2978,6 +2979,8 @@ 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. -- 2.39.2