In the Linux kernel, the following vulnerability has been resolved:
Revert "tty: n_gsm: fix UAF in gsm_cleanup_mux"
This reverts commit 9b9c8195f3f0d74a826077fc1c01b9ee74907239.
The commit above is reverted as it did not solve the original issue.
gsm_cleanup_mux() tries to free up the virtual ttys by calling
gsm_dlci_release() for each available DLCI. There, dlci_put() is called to
decrease the reference counter for the DLCI via tty_port_put() which
finally calls gsm_dlci_free(). This already clears the pointer which is
being checked in gsm_cleanup_mux() before calling gsm_dlci_release().
Therefore, it is not necessary to clear this pointer in gsm_cleanup_mux()
as done in the reverted commit. The commit introduces a null pointer
dereference:
<TASK>
? __die+0x1f/0x70
? page_fault_oops+0x156/0x420
? search_exception_tables+0x37/0x50
? fixup_exception+0x21/0x310
? exc_page_fault+0x69/0x150
? asm_exc_page_fault+0x26/0x30
? tty_port_put+0x19/0xa0
gsmtty_cleanup+0x29/0x80 [n_gsm]
release_one_tty+0x37/0xe0
process_one_work+0x1e6/0x3e0
worker_thread+0x4c/0x3d0
? __pfx_worker_thread+0x10/0x10
kthread+0xe1/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2f/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK>
The actual issue is that nothing guards dlci_put() from being called
multiple times while the tty driver was triggered but did not yet finished
calling gsm_dlci_free().
Metrics
Affected Vendors & Products
References
History
Tue, 07 Jan 2025 18:00:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Linux
Linux linux Kernel |
|
Weaknesses | CWE-476 | |
CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.6:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.6:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.6:rc3:*:*:*:*:*:* |
|
Vendors & Products |
Linux
Linux linux Kernel |
Mon, 04 Nov 2024 13:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Metrics |
ssvc
|

Status: PUBLISHED
Assigner: Linux
Published: 2024-03-02T21:59:36.867Z
Updated: 2025-05-04T12:49:15.207Z
Reserved: 2024-03-02T21:55:42.567Z
Link: CVE-2023-52564

Updated: 2024-08-02T23:03:20.987Z

Status : Analyzed
Published: 2024-03-02T22:15:48.933
Modified: 2025-01-07T17:34:18.947
Link: CVE-2023-52564
