In the Linux kernel, the following vulnerability has been resolved:

ovl: fix null pointer dereference in ovl_permission()

Following process:
P1 P2
path_lookupat
link_path_walk
inode_permission
ovl_permission
ovl_i_path_real(inode, &realpath)
path->dentry = ovl_i_dentry_upper(inode)
drop_cache
__dentry_kill(ovl_dentry)
iput(ovl_inode)
ovl_destroy_inode(ovl_inode)
dput(oi->__upperdentry)
dentry_kill(upperdentry)
dentry_unlink_inode
upperdentry->d_inode = NULL
realinode = d_inode(realpath.dentry) // return NULL
inode_permission(realinode)
inode->i_sb // NULL pointer dereference
, will trigger an null pointer dereference at realinode:
[ 335.664979] BUG: kernel NULL pointer dereference,
address: 0000000000000002
[ 335.668032] CPU: 0 PID: 2592 Comm: ls Not tainted 6.3.0
[ 335.669956] RIP: 0010:inode_permission+0x33/0x2c0
[ 335.678939] Call Trace:
[ 335.679165] <TASK>
[ 335.679371] ovl_permission+0xde/0x320
[ 335.679723] inode_permission+0x15e/0x2c0
[ 335.680090] link_path_walk+0x115/0x550
[ 335.680771] path_lookupat.isra.0+0xb2/0x200
[ 335.681170] filename_lookup+0xda/0x240
[ 335.681922] vfs_statx+0xa6/0x1f0
[ 335.682233] vfs_fstatat+0x7b/0xb0

Fetch a reproducer in [Link].

Use the helper ovl_i_path_realinode() to get realinode and then do
non-nullptr checking.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 15 Sep 2025 15:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ovl: fix null pointer dereference in ovl_permission() Following process: P1 P2 path_lookupat link_path_walk inode_permission ovl_permission ovl_i_path_real(inode, &realpath) path->dentry = ovl_i_dentry_upper(inode) drop_cache __dentry_kill(ovl_dentry) iput(ovl_inode) ovl_destroy_inode(ovl_inode) dput(oi->__upperdentry) dentry_kill(upperdentry) dentry_unlink_inode upperdentry->d_inode = NULL realinode = d_inode(realpath.dentry) // return NULL inode_permission(realinode) inode->i_sb // NULL pointer dereference , will trigger an null pointer dereference at realinode: [ 335.664979] BUG: kernel NULL pointer dereference, address: 0000000000000002 [ 335.668032] CPU: 0 PID: 2592 Comm: ls Not tainted 6.3.0 [ 335.669956] RIP: 0010:inode_permission+0x33/0x2c0 [ 335.678939] Call Trace: [ 335.679165] <TASK> [ 335.679371] ovl_permission+0xde/0x320 [ 335.679723] inode_permission+0x15e/0x2c0 [ 335.680090] link_path_walk+0x115/0x550 [ 335.680771] path_lookupat.isra.0+0xb2/0x200 [ 335.681170] filename_lookup+0xda/0x240 [ 335.681922] vfs_statx+0xa6/0x1f0 [ 335.682233] vfs_fstatat+0x7b/0xb0 Fetch a reproducer in [Link]. Use the helper ovl_i_path_realinode() to get realinode and then do non-nullptr checking.
Title ovl: fix null pointer dereference in ovl_permission()
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-09-15T14:46:31.919Z

Reserved: 2025-09-15T14:19:21.850Z

Link: CVE-2023-53260

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-09-15T15:15:53.430

Modified: 2025-09-15T15:22:27.090

Link: CVE-2023-53260

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.