{"id":"DEBIAN-CVE-2024-56633","details":"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-\u003esg.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 \u003c 0), we may   miss uncharging (msg-\u003esg.size - apply_bytes) bytes.  [...] 415 tosend = msg-\u003esg.size; 416 if (psock-\u003eapply_bytes && psock-\u003eapply_bytes \u003c tosend) 417   tosend = psock-\u003eapply_bytes; [...] 443 sk_msg_return(sk, msg, tosend); 444 release_sock(sk); 446 origsize = msg-\u003esg.size; 447 ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress, 448                             msg, tosend, flags); 449 sent = origsize - msg-\u003esg.size; [...] 454 lock_sock(sk); 455 if (unlikely(ret \u003c 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: \u003cTASK\u003e ? __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 \u003c/TASK\u003e ---[ 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 \u003c 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-\u003esg.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.","modified":"2026-09-15T09:02:59.986800430Z","published":"2024-12-27T15:15:22.933Z","upstream":["CVE-2024-56633"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-56633"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.123-1"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.115-1","6.1.119-1","6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-56633.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.5-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-56633.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.5-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-56633.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}