On 4/25/24 9:10AM, Jeongjun Park wrote:
Matthew Wilcox wrote:
If that's the problem then the correct place to detect & reject this is
during mount, not at inode free time.
I fixed the patch as you said. If you patch in this way, the
file system will not be affected by the vulnerability at all
due to the code structure.
Thanks.
---
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..ba0aa2f145cc 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;
@@ -339,6 +339,9 @@ 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));
+ if(agno >= MAXAG || agno < 0)
+ return -EIO;
That's the right idea, but move the new code after the call to
release_metapage().
release_metapage(mp);
