Linux Kernel: UAF in overlayfs mkdir debug print
CVE-2026-98921 Published on October 23, 2026

ovl: fix UAF in ovl_do_mkdir() debug print
In the Linux kernel, the following vulnerability has been resolved: ovl: fix UAF in ovl_do_mkdir() debug print ovl_do_mkdir() prints the input dentry with %pd after vfs_mkdir(). Since commit fe497f0759e0 ("VFS: change vfs_mkdir() to unlock on failure."), vfs_mkdir() calls end_creating() on the input dentry on failure and may replace it on success, so the post-call %pd can use-after-free the dentry when CONFIG_OVERLAY_FS_DEBUG is enabled. Print the dentry before the call and only the result afterward.

NVD

Products Associated with CVE-2026-98921

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Affected Versions

• Version fe497f0759e0efb949f9480911d00b6045c21f50 and below 719bd33ab359c539a68a278c15a97deb77565cdb is affected.
• Version fe497f0759e0efb949f9480911d00b6045c21f50 and below ae146bc1abdeb4607abf2975b858c053024e8ac1 is affected.

• Version 6.19 is affected.
• Before 6.19 is unaffected.
• Version 7.2.9, <= 7.2.* is unaffected.
• Version 7.3, <= * is unaffected.