In the Linux kernel, the following vulnerability has been resolved: ovl: keep err zero after successful ovl_cache_get() ovl_iterate_merged() stores PTR_ERR(cache) in err before checking IS_ERR(cache). On success err holds the truncated cache pointer and can be returned as a bogus non-zero error. The syzbot reproducer reaches this through overlay-on-overlay readdir: getdents64 iterate_dir(outer overlay file) ovl_iterate_merged() ovl_cache_get() ovl_dir_read_merged() ovl_dir_read() iterate_dir(inner overlay file) ovl_iterate_merged() Only compute PTR_ERR(cache) on the error path.

A flaw was found in the Linux kernel's overlay filesystem (ovl) component. Specifically, an issue in the `ovl_iterate_merged()` function incorrectly stores an error pointer even after a successful cache operation. This can lead to the function returning a misleading non-zero error, potentially causing unexpected behavior or instability within the system. This vulnerability is related to incorrect error handling during directory iteration.

Red Hat Enterprise Linux 10 Not affected kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-53174 https://nvd.nist.gov/vuln/detail/CVE-2026-53174 https://lore.kernel.org/linux-cve-announce/2026062553-CVE-2026-53174-1b7c@gregkh/T