Description
In the Linux kernel, the following vulnerability has been resolved:

tcp_bpf: Fix the sk_mem_uncharge logic in tcp_bpf_sendmsg

The current sk memory accounting logic in __SK_REDIRECT is pre-uncharging
tosend bytes, which is either msg->sg.size or a smaller value apply_bytes.

Potential problems with this strategy are as follows:

- If the actual sent bytes are smaller than tosend, we need to charge some
bytes back, as in line 487, which is okay but seems not clean.

- When tosend is set to apply_bytes, as in line 417, and (ret < 0), we may
miss uncharging (msg->sg.size - apply_bytes) bytes.

[...]
415 tosend = msg->sg.size;
416 if (psock->apply_bytes && psock->apply_bytes < tosend)
417 tosend = psock->apply_bytes;
[...]
443 sk_msg_return(sk, msg, tosend);
444 release_sock(sk);
446 origsize = msg->sg.size;
447 ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress,
448 msg, tosend, flags);
449 sent = origsize - msg->sg.size;
[...]
454 lock_sock(sk);
455 if (unlikely(ret < 0)) {
456 int free = sk_msg_free_nocharge(sk, msg);
458 if (!cork)
459 *copied -= free;
460 }
[...]
487 if (eval == __SK_REDIRECT)
488 sk_mem_charge(sk, tosend - sent);
[...]

When running the selftest test_txmsg_redir_wait_sndmem with txmsg_apply,
the following warning will be reported:

------------[ cut here ]------------
WARNING: CPU: 6 PID: 57 at net/ipv4/af_inet.c:156 inet_sock_destruct+0x190/0x1a0
Modules linked in:
CPU: 6 UID: 0 PID: 57 Comm: kworker/6:0 Not tainted 6.12.0-rc1.bm.1-amd64+ #43
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Workqueue: events sk_psock_destroy
RIP: 0010:inet_sock_destruct+0x190/0x1a0
RSP: 0018:ffffad0a8021fe08 EFLAGS: 00010206
RAX: 0000000000000011 RBX: ffff9aab4475b900 RCX: ffff9aab481a0800
RDX: 0000000000000303 RSI: 0000000000000011 RDI: ffff9aab4475b900
RBP: ffff9aab4475b990 R08: 0000000000000000 R09: ffff9aab40050ec0
R10: 0000000000000000 R11: ffff9aae6fdb1d01 R12: ffff9aab49c60400
R13: ffff9aab49c60598 R14: ffff9aab49c60598 R15: dead000000000100
FS: 0000000000000000(0000) GS:ffff9aae6fd80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffec7e47bd8 CR3: 00000001a1a1c004 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __warn+0x89/0x130
? inet_sock_destruct+0x190/0x1a0
? report_bug+0xfc/0x1e0
? handle_bug+0x5c/0xa0
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? inet_sock_destruct+0x190/0x1a0
__sk_destruct+0x25/0x220
sk_psock_destroy+0x2b2/0x310
process_scheduled_works+0xa3/0x3e0
worker_thread+0x117/0x240
? __pfx_worker_thread+0x10/0x10
kthread+0xcf/0x100
? __pfx_kthread+0x10/0x10
ret_from_fork+0x31/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
---[ end trace 0000000000000000 ]---

In __SK_REDIRECT, a more concise way is delaying the uncharging after sent
bytes are finalized, and uncharge this value. When (ret < 0), we shall
invoke sk_msg_free.

Same thing happens in case __SK_DROP, when tosend is set to apply_bytes,
we may miss uncharging (msg->sg.size - apply_bytes) bytes. The same
warning will be reported in selftest.

[...]
468 case __SK_DROP:
469 default:
470 sk_msg_free_partial(sk, msg, tosend);
471 sk_msg_apply_bytes(psock, tosend);
472 *copied -= (tosend + delta);
473 return -EACCES;
[...]

So instead of sk_msg_free_partial we can do sk_msg_free here.
Published: 2024-12-27
Score: 7.8 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories
Source ID Title
Debian DLA Debian DLA DLA-4075-1 linux security update
Debian DLA Debian DLA DLA-4076-1 linux-6.1 security update
EUVD EUVD EUVD-2024-53281 In the Linux kernel, the following vulnerability has been resolved: tcp_bpf: Fix the sk_mem_uncharge logic in tcp_bpf_sendmsg The current sk memory accounting logic in __SK_REDIRECT is pre-uncharging tosend bytes, which is either msg->sg.size or a smaller value apply_bytes. Potential problems with this strategy are as follows: - If the actual sent bytes are smaller than tosend, we need to charge some bytes back, as in line 487, which is okay but seems not clean. - When tosend is set to apply_bytes, as in line 417, and (ret < 0), we may miss uncharging (msg->sg.size - apply_bytes) bytes. [...] 415 tosend = msg->sg.size; 416 if (psock->apply_bytes && psock->apply_bytes < tosend) 417 tosend = psock->apply_bytes; [...] 443 sk_msg_return(sk, msg, tosend); 444 release_sock(sk); 446 origsize = msg->sg.size; 447 ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress, 448 msg, tosend, flags); 449 sent = origsize - msg->sg.size; [...] 454 lock_sock(sk); 455 if (unlikely(ret < 0)) { 456 int free = sk_msg_free_nocharge(sk, msg); 458 if (!cork) 459 *copied -= free; 460 } [...] 487 if (eval == __SK_REDIRECT) 488 sk_mem_charge(sk, tosend - sent); [...] When running the selftest test_txmsg_redir_wait_sndmem with txmsg_apply, the following warning will be reported: ------------[ cut here ]------------ WARNING: CPU: 6 PID: 57 at net/ipv4/af_inet.c:156 inet_sock_destruct+0x190/0x1a0 Modules linked in: CPU: 6 UID: 0 PID: 57 Comm: kworker/6:0 Not tainted 6.12.0-rc1.bm.1-amd64+ #43 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Workqueue: events sk_psock_destroy RIP: 0010:inet_sock_destruct+0x190/0x1a0 RSP: 0018:ffffad0a8021fe08 EFLAGS: 00010206 RAX: 0000000000000011 RBX: ffff9aab4475b900 RCX: ffff9aab481a0800 RDX: 0000000000000303 RSI: 0000000000000011 RDI: ffff9aab4475b900 RBP: ffff9aab4475b990 R08: 0000000000000000 R09: ffff9aab40050ec0 R10: 0000000000000000 R11: ffff9aae6fdb1d01 R12: ffff9aab49c60400 R13: ffff9aab49c60598 R14: ffff9aab49c60598 R15: dead000000000100 FS: 0000000000000000(0000) GS:ffff9aae6fd80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffec7e47bd8 CR3: 00000001a1a1c004 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ? __warn+0x89/0x130 ? inet_sock_destruct+0x190/0x1a0 ? report_bug+0xfc/0x1e0 ? handle_bug+0x5c/0xa0 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? inet_sock_destruct+0x190/0x1a0 __sk_destruct+0x25/0x220 sk_psock_destroy+0x2b2/0x310 process_scheduled_works+0xa3/0x3e0 worker_thread+0x117/0x240 ? __pfx_worker_thread+0x10/0x10 kthread+0xcf/0x100 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x40 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> ---[ end trace 0000000000000000 ]--- In __SK_REDIRECT, a more concise way is delaying the uncharging after sent bytes are finalized, and uncharge this value. When (ret < 0), we shall invoke sk_msg_free. Same thing happens in case __SK_DROP, when tosend is set to apply_bytes, we may miss uncharging (msg->sg.size - apply_bytes) bytes. The same warning will be reported in selftest. [...] 468 case __SK_DROP: 469 default: 470 sk_msg_free_partial(sk, msg, tosend); 471 sk_msg_apply_bytes(psock, tosend); 472 *copied -= (tosend + delta); 473 return -EACCES; [...] So instead of sk_msg_free_partial we can do sk_msg_free here.
Ubuntu USN Ubuntu USN USN-7379-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7379-2 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7380-1 Linux kernel (Low Latency) vulnerabilities
Ubuntu USN Ubuntu USN USN-7381-1 Linux kernel (Low Latency) vulnerabilities
Ubuntu USN Ubuntu USN USN-7382-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7387-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7387-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7387-3 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7388-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7389-1 Linux kernel (NVIDIA Tegra) vulnerabilities
Ubuntu USN Ubuntu USN USN-7390-1 Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7391-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7392-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7392-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7392-3 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7392-4 Linux kernel (AWS FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7393-1 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7401-1 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7407-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7413-1 Linux kernel (IoT) vulnerabilities
Ubuntu USN Ubuntu USN USN-7421-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7449-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7449-2 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7450-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7451-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7452-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7453-1 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7458-1 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7459-1 Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN Ubuntu USN USN-7459-2 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7463-1 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7468-1 Linux kernel (Azure, N-Series) vulnerabilities
Ubuntu USN Ubuntu USN USN-7523-1 Linux kernel (Raspberry Pi Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7524-1 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7539-1 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7540-1 Linux kernel (Raspberry Pi) vulnerabilities
History

Mon, 03 Nov 2025 21:30:00 +0000


Tue, 07 Oct 2025 19:00:00 +0000

Type Values Removed Values Added
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Wed, 16 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00068}

epss

{'score': 0.00051}


Thu, 13 Feb 2025 00:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-99
Metrics threat_severity

Low

threat_severity

Moderate


Sat, 28 Dec 2024 13:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low


Fri, 27 Dec 2024 15:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: tcp_bpf: Fix the sk_mem_uncharge logic in tcp_bpf_sendmsg The current sk memory accounting logic in __SK_REDIRECT is pre-uncharging tosend bytes, which is either msg->sg.size or a smaller value apply_bytes. Potential problems with this strategy are as follows: - If the actual sent bytes are smaller than tosend, we need to charge some bytes back, as in line 487, which is okay but seems not clean. - When tosend is set to apply_bytes, as in line 417, and (ret < 0), we may miss uncharging (msg->sg.size - apply_bytes) bytes. [...] 415 tosend = msg->sg.size; 416 if (psock->apply_bytes && psock->apply_bytes < tosend) 417 tosend = psock->apply_bytes; [...] 443 sk_msg_return(sk, msg, tosend); 444 release_sock(sk); 446 origsize = msg->sg.size; 447 ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress, 448 msg, tosend, flags); 449 sent = origsize - msg->sg.size; [...] 454 lock_sock(sk); 455 if (unlikely(ret < 0)) { 456 int free = sk_msg_free_nocharge(sk, msg); 458 if (!cork) 459 *copied -= free; 460 } [...] 487 if (eval == __SK_REDIRECT) 488 sk_mem_charge(sk, tosend - sent); [...] When running the selftest test_txmsg_redir_wait_sndmem with txmsg_apply, the following warning will be reported: ------------[ cut here ]------------ WARNING: CPU: 6 PID: 57 at net/ipv4/af_inet.c:156 inet_sock_destruct+0x190/0x1a0 Modules linked in: CPU: 6 UID: 0 PID: 57 Comm: kworker/6:0 Not tainted 6.12.0-rc1.bm.1-amd64+ #43 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Workqueue: events sk_psock_destroy RIP: 0010:inet_sock_destruct+0x190/0x1a0 RSP: 0018:ffffad0a8021fe08 EFLAGS: 00010206 RAX: 0000000000000011 RBX: ffff9aab4475b900 RCX: ffff9aab481a0800 RDX: 0000000000000303 RSI: 0000000000000011 RDI: ffff9aab4475b900 RBP: ffff9aab4475b990 R08: 0000000000000000 R09: ffff9aab40050ec0 R10: 0000000000000000 R11: ffff9aae6fdb1d01 R12: ffff9aab49c60400 R13: ffff9aab49c60598 R14: ffff9aab49c60598 R15: dead000000000100 FS: 0000000000000000(0000) GS:ffff9aae6fd80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffec7e47bd8 CR3: 00000001a1a1c004 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ? __warn+0x89/0x130 ? inet_sock_destruct+0x190/0x1a0 ? report_bug+0xfc/0x1e0 ? handle_bug+0x5c/0xa0 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? inet_sock_destruct+0x190/0x1a0 __sk_destruct+0x25/0x220 sk_psock_destroy+0x2b2/0x310 process_scheduled_works+0xa3/0x3e0 worker_thread+0x117/0x240 ? __pfx_worker_thread+0x10/0x10 kthread+0xcf/0x100 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x40 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> ---[ end trace 0000000000000000 ]--- In __SK_REDIRECT, a more concise way is delaying the uncharging after sent bytes are finalized, and uncharge this value. When (ret < 0), we shall invoke sk_msg_free. Same thing happens in case __SK_DROP, when tosend is set to apply_bytes, we may miss uncharging (msg->sg.size - apply_bytes) bytes. The same warning will be reported in selftest. [...] 468 case __SK_DROP: 469 default: 470 sk_msg_free_partial(sk, msg, tosend); 471 sk_msg_apply_bytes(psock, tosend); 472 *copied -= (tosend + delta); 473 return -EACCES; [...] So instead of sk_msg_free_partial we can do sk_msg_free here.
Title tcp_bpf: Fix the sk_mem_uncharge logic in tcp_bpf_sendmsg
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-05-11T20:56:15.744Z

Reserved: 2024-12-27T15:00:39.838Z

Link: CVE-2024-56633

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2024-12-27T15:15:22.933

Modified: 2025-11-03T21:18:11.540

Link: CVE-2024-56633

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-12-27T00:00:00Z

Links: CVE-2024-56633 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-07-12T22:31:42Z

Weaknesses