From: Edward Adam Davis Date: Thu, 20 Feb 2025 11:24:19 +0000 (+0800) Subject: jfs: add sanity check for agwidth in dbMount X-Git-Tag: v6.15-rc1~147^2~2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ddf2846f22e8575d6b4b6a66f2100f168b8cd73d;p=thirdparty%2Fkernel%2Flinux.git jfs: add sanity check for agwidth in dbMount The width in dmapctl of the AG is zero, it trigger a divide error when calculating the control page level in dbAllocAG. To avoid this issue, add a check for agwidth in dbAllocAG. Reported-and-tested-by: syzbot+7c808908291a569281a9@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7c808908291a569281a9 Signed-off-by: Edward Adam Davis Signed-off-by: Dave Kleikamp --- diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c index 9ac1fc2ed05bc..0e1019382cf51 100644 --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -204,6 +204,10 @@ int dbMount(struct inode *ipbmap) bmp->db_aglevel = le32_to_cpu(dbmp_le->dn_aglevel); bmp->db_agheight = le32_to_cpu(dbmp_le->dn_agheight); bmp->db_agwidth = le32_to_cpu(dbmp_le->dn_agwidth); + if (!bmp->db_agwidth) { + err = -EINVAL; + goto err_release_metapage; + } bmp->db_agstart = le32_to_cpu(dbmp_le->dn_agstart); bmp->db_agl2size = le32_to_cpu(dbmp_le->dn_agl2size); if (bmp->db_agl2size > L2MAXL2SIZE - L2MAXAG ||