From: Manas Ghandat <ghandatmanas@xxxxxxxxx> [ Upstream commit 05d9ea1ceb62a55af6727a69269a4fd310edf483 ] Currently there is not check against the agno of the iag while allocating new inodes to avoid fragmentation problem. Added the check which is required. Reported-by: syzbot+79d792676d8ac050949f@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=79d792676d8ac050949f Signed-off-by: Manas Ghandat <ghandatmanas@xxxxxxxxx> Signed-off-by: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/jfs/jfs_imap.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c index 67c67604b8c85..14f918a4831d3 100644 --- a/fs/jfs/jfs_imap.c +++ b/fs/jfs/jfs_imap.c @@ -1322,7 +1322,7 @@ diInitInode(struct inode *ip, int iagno, int ino, int extno, struct iag * iagp) int diAlloc(struct inode *pip, bool dir, struct inode *ip) { int rc, ino, iagno, addext, extno, bitno, sword; - int nwords, rem, i, agno; + int nwords, rem, i, agno, dn_numag; u32 mask, inosmap, extsmap; struct inode *ipimap; struct metapage *mp; @@ -1358,6 +1358,9 @@ int diAlloc(struct inode *pip, bool dir, struct inode *ip) /* get the ag number of this iag */ agno = BLKTOAG(JFS_IP(pip)->agstart, JFS_SBI(pip->i_sb)); + dn_numag = JFS_SBI(pip->i_sb)->bmap->db_numag; + if (agno < 0 || agno > dn_numag) + return -EIO; if (atomic_read(&JFS_SBI(pip->i_sb)->bmap->db_active[agno])) { /* -- 2.42.0
