Re: [PATCH] jfs: Fix array-index-out-of-bounds in diFree

Jeongjun Park
2024-04-26T03:42:03Z

Matthew Wilcox wrote:
> This is not a good commit message.

> > + if(agno >= MAXAG || agno < 0)
>
> Please follow normal kernel whitespace rules -- one space between 'if'
> and the open paren.

Has confirmed. This is a patch that re-edited the relevant part to
comply with the rules.

Thanks.

Reported-by: syzbot+241c815bda521982cb49@syzkaller.appspotmail.com
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
---
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 2ec35889ad24..1407feccbc2d 100644
--- a/fs/jfs/jfs_imap.c
+++ b/fs/jfs/jfs_imap.c
@@ -290,7 +290,7 @@ int diSync(struct inode *ipimap)
int diRead(struct inode *ip)
{
struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
- int iagno, ino, extno, rc;
+ int iagno, ino, extno, rc, agno;
struct inode *ipimap;
struct dinode *dp;
struct iag *iagp;
@@ -339,8 +339,11 @@ int diRead(struct inode *ip)

/* get the ag for the iag */
agstart = le64_to_cpu(iagp->agstart);
+ agno = BLKTOAG(agstart, JFS_SBI(ip->i_sb));

release_metapage(mp);
+ if (agno >= MAXAG || agno < 0)
+ return -EIO;

rel_inode = (ino & (INOSPERPAGE - 1));
pageno = blkno >> sbi->l2nbperpage;
--
2.34.1