CVE-2025-21705
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2025-21705
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21705.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2025-21705
- Downstream
- Related
- Published
- 2025-02-27T02:07:19Z
- Modified
- 2025-10-17T22:26:39.557551Z
- Summary
- mptcp: handle fastopen disconnect correctly
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
mptcp: handle fastopen disconnect correctly
Syzbot was able to trigger a data stream corruption:
WARNING: CPU: 0 PID: 9846 at net/mptcp/protocol.c:1024 mptcpcleanuna+0xddb/0xff0 net/mptcp/protocol.c:1024 Modules linked in: CPU: 0 UID: 0 PID: 9846 Comm: syz-executor351 Not tainted 6.13.0-rc2-syzkaller-00059-g00a5acdbf398 #0 Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 RIP: 0010:mptcpcleanuna+0xddb/0xff0 net/mptcp/protocol.c:1024 Code: fa ff ff 48 8b 4c 24 18 80 e1 07 fe c1 38 c1 0f 8c 8e fa ff ff 48 8b 7c 24 18 e8 e0 db 54 f6 e9 7f fa ff ff e8 e6 80 ee f5 90 <0f> 0b 90 4c 8b 6c 24 40 4d 89 f4 e9 04 f5 ff ff 44 89 f1 80 e1 07 RSP: 0018:ffffc9000c0cf400 EFLAGS: 00010293 RAX: ffffffff8bb0dd5a RBX: ffff888033f5d230 RCX: ffff888059ce8000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000c0cf518 R08: ffffffff8bb0d1dd R09: 1ffff110170c8928 R10: dffffc0000000000 R11: ffffed10170c8929 R12: 0000000000000000 R13: ffff888033f5d220 R14: dffffc0000000000 R15: ffff8880592b8000 FS: 00007f6e866496c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6e86f491a0 CR3: 00000000310e6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> mptcpcleanunawakeup+0x7f/0x2d0 net/mptcp/protocol.c:1074 mptcpreleasecb+0x7cb/0xb30 net/mptcp/protocol.c:3493 releasesock+0x1aa/0x1f0 net/core/sock.c:3640 inetwaitforconnect net/ipv4/afinet.c:609 [inline] _inetstreamconnect+0x8bd/0xf30 net/ipv4/afinet.c:703 mptcpsendmsgfastopen+0x2a2/0x530 net/mptcp/protocol.c:1755 mptcpsendmsg+0x1884/0x1b10 net/mptcp/protocol.c:1830 socksendmsgnosec net/socket.c:711 [inline] _socksendmsg+0x1a6/0x270 net/socket.c:726 _syssendmsg+0x52a/0x7e0 net/socket.c:2583 _syssendmsg net/socket.c:2637 [inline] _syssendmsg+0x269/0x350 net/socket.c:2669 dosyscallx64 arch/x86/entry/common.c:52 [inline] dosyscall64+0xf3/0x230 arch/x86/entry/common.c:83 entrySYSCALL64afterhwframe+0x77/0x7f RIP: 0033:0x7f6e86ebfe69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 1f 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6e86649168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f6e86f491b8 RCX: 00007f6e86ebfe69 RDX: 0000000030004001 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007f6e86f491b0 R08: 00007f6e866496c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6e86f491bc R13: 000000000000006e R14: 00007ffe445d9420 R15: 00007ffe445d9508 </TASK>
The root cause is the bad handling of disconnect() generated internally by the MPTCP protocol in case of connect FASTOPEN errors.
Address the issue increasing the socket disconnect counter even on such a case, to allow other threads waiting on the same socket lock to properly error out.
- References
-
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/0263fb2e7b7b88075a5d86e74c4384ee4400828d
- https://git.kernel.org/stable/c/619af16b3b57a3a4ee50b9a30add9ff155541e71
- https://git.kernel.org/stable/c/6ec806762318a4adde0ea63342d42d0feae95079
- https://git.kernel.org/stable/c/73e268b4be27b36ae68ea10755cb003f43b38884
- https://git.kernel.org/stable/c/84ac44d9fed3a56440971cbd7600a02b70b5b32a
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedb7bb71dfb541df376c21c24451369fea83c4f327Fixed73e268b4be27b36ae68ea10755cb003f43b38884
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedc2b2ae3925b65070adb27d5a31a31c376f26dec7Fixed0263fb2e7b7b88075a5d86e74c4384ee4400828d
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedc2b2ae3925b65070adb27d5a31a31c376f26dec7Fixed84ac44d9fed3a56440971cbd7600a02b70b5b32a
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedc2b2ae3925b65070adb27d5a31a31c376f26dec7Fixed6ec806762318a4adde0ea63342d42d0feae95079
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedc2b2ae3925b65070adb27d5a31a31c376f26dec7Fixed619af16b3b57a3a4ee50b9a30add9ff155541e71
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedLast affected9c998d59a6b1359ad43d1ef38538af5f55fd01a2