Messages in this thread | | | Date | Wed, 24 Apr 2024 18:41:48 +0100 | From | Matthew Wilcox <> | Subject | Re: [PATCH] jfs: Fix array-index-out-of-bounds in diFree |
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On Thu, Apr 25, 2024 at 02:22:40AM +0900, Jeongjun Park wrote: > Due to overflow, a value that is too large is entered into the agno > value. Therefore, we need to add code to check the agno value.
This is clearly wrong.
#define BLKTOAG(b,sbi) ((b) >> ((sbi)->bmap->db_agl2size))
I'd suggest that something has either corrupted the sbi->bmap pointer or the sbi->bmap->db_agl2size value.
All your patch does is cover up the problem, not fix it.
> Reported-by: syzbot+241c815bda521982cb49@syzkaller.appspotmail.com > Signed-off-by: Jeongjun Park <aha310510@gmail.com> > --- > fs/jfs/jfs_imap.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c > index 2ec35889ad24..0aac083bc0db 100644 > --- a/fs/jfs/jfs_imap.c > +++ b/fs/jfs/jfs_imap.c > @@ -881,6 +881,11 @@ int diFree(struct inode *ip) > */ > agno = BLKTOAG(JFS_IP(ip)->agstart, JFS_SBI(ip->i_sb)); > > + if(agno >= MAXAG || agno < 0){ > + jfs_error(ip->i_sb, "invalid array index (0 <= agno < MAXAG), agno = %d\n", agno); > + return -ENOMEM; > + } > + > /* Lock the AG specific inode map information > */ > AG_LOCK(imap, agno); > -- > 2.34.1 >
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