CVE-2025-21683

bpf: Fix bpf_sk_select_reuseport() memory leak

MEDIUM

5.5

CVSS Score

Published: January 31, 2025 at 11:25 AM UTC

Updated: October 15, 2026 at 01:03 AM UTC

2 products affected across 2 vendorsLinux KernelSIMATIC S7-1500 TM MFP

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Severity

MEDIUM5.5

Exploit prediction

EPSS 0.2%

SSVC

No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix bpf_sk_select_reuseport() memory leak As pointed out in the original comment, lookup in sockmap can return a TCP ESTABLISHED socket. Such TCP socket may have had SO_ATTACH_REUSEPORT_EBPF set before it was ESTABLISHED. In other words, a non-NULL sk_reuseport_cb does not imply a non-refcounted socket. Drop sk's reference in both error paths. unreferenced object 0xffff888101911800 (size 2048): comm "test_progs", pid 44109, jiffies 4297131437 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 80 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 9336483b): __kmalloc_noprof+0x3bf/0x560 __reuseport_alloc+0x1d/0x40 reuseport_alloc+0xca/0x150 reuseport_attach_prog+0x87/0x140 sk_reuseport_attach_bpf+0xc8/0x100 sk_setsockopt+0x1181/0x1990 do_sock_setsockopt+0x12b/0x160 __sys_setsockopt+0x7b/0xc0 __x64_sys_setsockopt+0x1b/0x30 do_syscall_64+0x93/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Affected

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

Linux Kernel · Linux

95%

5.16 ≤ v < 6.1.1275.8 ≤ v < 5.10.2345.8 ≤ v < 5.15.1775.8 ≤ v < 6.1.1275.8 ≤ v < 6.12.115.8 ≤ v < 6.135.8 ≤ v < 6.6.746.2 ≤ v < 6.6.746.7 ≤ v < 6.12.116.13 rc1 6.13 rc2 6.13 rc3 6.13 rc4 6.13 rc5 6.13 rc6 6.13 rc764d85290d79c0677edb5a8ee2295b36c022fa5df

Vendor states this is fixed in 0ab52a8ca6e156a64c51b5e7456cac9a0ebfd9bf (fixed)

Vendor states this is fixed in b02e70be498b138e9c21701c2f33f4018ca7cd5e (fixed)

Vendor states this is fixed in b3af60928ab9129befa65e6df0310d27300942bf (fixed)

Vendor states this is fixed in bb36838dac7bb334a3f3d7eb29875593ec9473fc (fixed)

Vendor states this is fixed in cccd51dd22574216e64e5d205489e634f86999f3 (fixed)

Vendor states this is fixed in d0a3b3d1176d39218b8edb2a2d03164942ab9ccd (fixed)

Vendor states this is fixed in 5.10.234 (unaffected)

Vendor states this is fixed in 5.15.177 (unaffected)

Vendor states this is fixed in 5.8 (unaffected)

Vendor states this is fixed in 6.1.127 (unaffected)

Vendor states this is fixed in 6.12.11 (unaffected)

Vendor states this is fixed in 6.13 (unaffected)