On 10/8/24 3:21PM, Nihar Chaithanya wrote:
When the value of lp is 1 at the end of the iteration in the for loop,
lp is modified in the next iteration to a negative value.
Add a check to prevent this condition.
Reported-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=412dea214d8baa3f7483
Tested-by: [email protected]
Signed-off-by: Nihar Chaithanya <[email protected]>
---
fs/jfs/jfs_dmap.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 5713994328cb..3ebb2dfdd0b3 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -2911,6 +2911,12 @@ static void dbAdjTree(dmtree_t *tp, int leafno, int
newval, bool is_ctl)
*/
tp->dmt_stree[pp] = max;
+ /* check to prevent negative value of lp on the
+ * next iteration.
+ */
+ if (lp == 1)
+ break;
+
I'm going to change this a little bit. I think it's a little cleaner to
test lp for zero at the top of the loop.
/* parent becomes leaf for next go-round.
*/
lp = pp;
That and rewording the commit message, I will apply this.
Thanks,
Shaggy
