CVE-2022-49307: tty: synclink_gt: Fix null-pointer-dereference in slgt_clean()

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-02-26 · updated 2026-06-17
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: tty: synclink_gt: Fix null-pointer-dereference in slgt_clean() When the driver fails at alloc_hdlcdev(), and then we remove the driver module, we will get the following splat: [ 25.065966] general protection fault, probably for non-canonical address 0xdffffc0000000182: 0000 [#1] PREEMPT SMP KASAN PTI [ 25.066914] KASAN: null-ptr-deref in range [0x0000000000000c10-0x0000000000000c17] [ 25.069262] RIP: 0010:detach_hdlc_protocol+0x2a/0x3e0 [ 25.077709] Call Trace: [ 25.077924] <TASK> [ 25.078108] unregister_hdlc_device+0x16/0x30 [ 25.078481] slgt_cleanup+0x157/0x9f0 [synclink_gt] Fix this by checking whether the 'info->netdev' is a null pointer first.

Affected products

Linux kernel: before 4.9.318; from 4.10 before 4.14.283; from 4.15 before 4.19.247; from 4.20 before 5.4.198; from 5.5 before 5.10.122; from 5.11 before 5.15.47 — fixed in 4.14.283, 4.19.247, 4.9.318, 5.10.122, 5.15.47, 5.17.15

How to fix

Upgrade to a fixed version: Linux kernel 4.14.283, 4.19.247, 4.9.318, 5.10.122. Check the vendor advisory for mitigations.

References

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