CVE-2023-53121

tcp: tcp_make_synack() can be called from process context

MEDIUM

5.5

CVSS Score

Published: May 2, 2025 at 03:55 PM UTC

Updated: June 17, 2026 at 06:44 AM UTC

1 product affected across 1 vendorLinux Kernel

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Severity

MEDIUM5.5

Exploit prediction

EPSS 0.2%

Description

In the Linux kernel, the following vulnerability has been resolved: tcp: tcp_make_synack() can be called from process context tcp_rtx_synack() now could be called in process context as explained in 0a375c822497 ("tcp: tcp_rtx_synack() can be called from process context"). tcp_rtx_synack() might call tcp_make_synack(), which will touch per-CPU variables with preemption enabled. This causes the following BUG: BUG: using __this_cpu_add() in preemptible [00000000] code: ThriftIO1/5464 caller is tcp_make_synack+0x841/0xac0 Call Trace: <TASK> dump_stack_lvl+0x10d/0x1a0 check_preemption_disabled+0x104/0x110 tcp_make_synack+0x841/0xac0 tcp_v6_send_synack+0x5c/0x450 tcp_rtx_synack+0xeb/0x1f0 inet_rtx_syn_ack+0x34/0x60 tcp_check_req+0x3af/0x9e0 tcp_rcv_state_process+0x59b/0x2030 tcp_v6_do_rcv+0x5f5/0x700 release_sock+0x3a/0xf0 tcp_sendmsg+0x33/0x40 ____sys_sendmsg+0x2f2/0x490 __sys_sendmsg+0x184/0x230 do_syscall_64+0x3d/0x90 Avoid calling __TCP_INC_STATS() with will touch per-cpu variables. Use TCP_INC_STATS() which is safe to be called from context switch.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Linux Kernel · Linux

95%

3.7 ≤ v < 4.14.3113.7 ≤ v < 4.19.2793.7 ≤ v < 5.10.1763.7 ≤ v < 5.15.1043.7 ≤ v < 5.4.2383.7 ≤ v < 6.1.213.7 ≤ v < 6.2.83.7 ≤ v < 6.34.15 ≤ v < 4.19.2794.20 ≤ v < 5.4.2385.11 ≤ v < 5.15.1045.16 ≤ v < 6.1.215.5 ≤ v < 5.10.1766.2 ≤ v < 6.2.83.7 6.3 rc1 6.3 rc28336886f786fdacbc19b719c1f7ea91eb70706d4

Vendor states this is fixed in 442aa78ed70188b21ccd8669738448702c0a3281 (fixed)

Vendor states this is fixed in 7613cde8c0c1f02a7ec2e1d536c01b65b135fc1c (fixed)

Vendor states this is fixed in 77ad58bca0119e8cc3e0e9d91a3f22caa66e4dfa (fixed)

Vendor states this is fixed in 9180aa4622a720b433e842b4d3aa34d73eec577a (fixed)

Vendor states this is fixed in ad07290d63ff6689f50565b02f5b6f34ec15a5ca (fixed)

Vendor states this is fixed in bced3f7db95ff2e6ca29dc4d1c9751ab5e736a09 (fixed)

Vendor states this is fixed in d493d4fe88195a144d6a277a90062a7534ed2192 (fixed)

Vendor states this is fixed in e23ca307745be3df7fe9762f3e2a7e311a57852e (fixed)

Vendor states this is fixed in 3.7 (unaffected)

Vendor states this is fixed in 4.14.311 (unaffected)

Vendor states this is fixed in 4.19.279 (unaffected)

Vendor states this is fixed in 5.10.176 (unaffected)