Re: [syzbot] [syzbot] [jfs?] KASAN: slab-out-of-bounds Write in diWrite

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Subject: [syzbot] [jfs?] KASAN: slab-out-of-bounds Write in diWrite
Author: lizhi.xu@xxxxxxxxxxxxx

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git ed30a4a51bb1

diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c
index 2ec35889ad24..84c9abb0fa71 100644
--- a/fs/jfs/jfs_imap.c
+++ b/fs/jfs/jfs_imap.c
@@ -746,7 +746,9 @@ int diWrite(tid_t tid, struct inode *ip)
 		p = (dtpage_t *) &jfs_ip->i_dtroot;
 		xp = (dtpage_t *) & dp->di_dtroot;
 		lv = ilinelock->lv;
-		for (n = 0; n < ilinelock->index; n++, lv++) {
+		printk("sp ms: %d, dp ms: %d, %s\n", p->header.maxslot, xp->header.maxslot, __func__);
+		if (p->header.maxslot < DTPAGEMAXSLOT && xp->header.maxslot < DTPAGEMAXSLOT)
+		for (n = 0; n < ilinelock->index && lv->offset < DTPAGEMAXSLOT; n++, lv++) {
 			memcpy(&xp->slot[lv->offset], &p->slot[lv->offset],
 			       lv->length << L2DTSLOTSIZE);
 		}