Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix cifsFileInfo reference leak in deferred close When cifs_close() defers a close, it hands the cifsFileInfo reference of the closing struct file to the queued work. Each execution of smb2_deferred_work_close() drops one such reference. deferred_close_scheduled can be false while the work is pending: the workqueue clears PENDING when the callback starts to run, before the callback clears the flag under deferred_lock. A close in that interval requeues the running work, and the callback then clears the flag, leaving the requeued work pending with the flag down. A later cifs_open() can reuse the handle and its cifs_close() reaches the same branch: queue_delayed_work() fails because the work is still pending, but cifs_close() returns without dropping the closing file's reference. The cifsFileInfo count stays pinned and its tlink, dentry and server handle are leaked. Check the return value and hand off the reference only when work was actually queued. Otherwise, use the shared _cifsFileInfo_put(), like the mod_delayed_work() branch above: the pending execution already owns its reference. This issue was found by an in-house static analysis tool.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
c3f207ab29f793b8c942ce8067ed123f18d5b81b to < 645a7359c1f740152464edf84f1030e0cad42c9daffectedc3f207ab29f793b8c942ce8067ed123f18d5b81b to < 46d98be6c34a52182ea3c2f849a3ea0e9419eaf2affectedc3f207ab29f793b8c942ce8067ed123f18d5b81b to < 525c225e23d61694091f2806de553a69362a78ffaffectedc3f207ab29f793b8c942ce8067ed123f18d5b81b to < bbeb7a42c9ea656e17ddcbdc2d7917aa853383a6affectedc3f207ab29f793b8c942ce8067ed123f18d5b81b to < a6767712902beb0f53238be485971c9a83ea1079affectedc3f207ab29f793b8c942ce8067ed123f18d5b81b to < ea93759d6c2789924f4e557aed5be532207715eaaffectedc3f207ab29f793b8c942ce8067ed123f18d5b81b to < 5520e89a5a4f834bced64cf2ac927001cc513a40affected
Linux Linux
Default version status: affected
5.13affected0 to < 5.13unaffected5.15.224 to ≤ 5.15.*unaffected6.1.191 to ≤ 6.1.*unaffected6.6.160 to ≤ 6.6.*unaffected6.12.113 to ≤ 6.12.*unaffected6.18.54 to ≤ 6.18.*unaffected7.2.7 to ≤ 7.2.*unaffected7.3 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/645a7359c1f740152464edf84f1030e0cad42c9d ↗
- https://git.kernel.org/stable/c/46d98be6c34a52182ea3c2f849a3ea0e9419eaf2 ↗
- https://git.kernel.org/stable/c/525c225e23d61694091f2806de553a69362a78ff ↗
- https://git.kernel.org/stable/c/bbeb7a42c9ea656e17ddcbdc2d7917aa853383a6 ↗
- https://git.kernel.org/stable/c/a6767712902beb0f53238be485971c9a83ea1079 ↗
- https://git.kernel.org/stable/c/ea93759d6c2789924f4e557aed5be532207715ea ↗
- https://git.kernel.org/stable/c/5520e89a5a4f834bced64cf2ac927001cc513a40 ↗