{"id":"DEBIAN-CVE-2024-36905","details":"In the Linux kernel, the following vulnerability has been resolved:  tcp: defer shutdown(SEND_SHUTDOWN) for TCP_SYN_RECV sockets  TCP_SYN_RECV state is really special, it is only used by cross-syn connections, mostly used by fuzzers.  In the following crash [1], syzbot managed to trigger a divide by zero in tcp_rcv_space_adjust()  A socket makes the following state transitions, without ever calling tcp_init_transfer(), meaning tcp_init_buffer_space() is also not called.           TCP_CLOSE connect()          TCP_SYN_SENT          TCP_SYN_RECV shutdown() -\u003e tcp_shutdown(sk, SEND_SHUTDOWN)          TCP_FIN_WAIT1  To fix this issue, change tcp_shutdown() to not perform a TCP_SYN_RECV -\u003e TCP_FIN_WAIT1 transition, which makes no sense anyway.  When tcp_rcv_state_process() later changes socket state from TCP_SYN_RECV to TCP_ESTABLISH, then look at sk-\u003esk_shutdown to finally enter TCP_FIN_WAIT1 state, and send a FIN packet from a sane socket state.  This means tcp_send_fin() can now be called from BH context, and must use GFP_ATOMIC allocations.  [1] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 1 PID: 5084 Comm: syz-executor358 Not tainted 6.9.0-rc6-syzkaller-00022-g98369dccd2f8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024  RIP: 0010:tcp_rcv_space_adjust+0x2df/0x890 net/ipv4/tcp_input.c:767 Code: e3 04 4c 01 eb 48 8b 44 24 38 0f b6 04 10 84 c0 49 89 d5 0f 85 a5 03 00 00 41 8b 8e c8 09 00 00 89 e8 29 c8 48 0f af c3 31 d2 \u003c48\u003e f7 f1 48 8d 1c 43 49 8d 96 76 08 00 00 48 89 d0 48 c1 e8 03 48 RSP: 0018:ffffc900031ef3f0 EFLAGS: 00010246 RAX: 0c677a10441f8f42 RBX: 000000004fb95e7e RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000027d4b11f R08: ffffffff89e535a4 R09: 1ffffffff25e6ab7 R10: dffffc0000000000 R11: ffffffff8135e920 R12: ffff88802a9f8d30 R13: dffffc0000000000 R14: ffff88802a9f8d00 R15: 1ffff1100553f2da FS:  00005555775c0380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1155bf2304 CR3: 000000002b9f2000 CR4: 0000000000350ef0 Call Trace:  \u003cTASK\u003e   tcp_recvmsg_locked+0x106d/0x25a0 net/ipv4/tcp.c:2513   tcp_recvmsg+0x25d/0x920 net/ipv4/tcp.c:2578   inet6_recvmsg+0x16a/0x730 net/ipv6/af_inet6.c:680   sock_recvmsg_nosec net/socket.c:1046 [inline]   sock_recvmsg+0x109/0x280 net/socket.c:1068   ____sys_recvmsg+0x1db/0x470 net/socket.c:2803   ___sys_recvmsg net/socket.c:2845 [inline]   do_recvmmsg+0x474/0xae0 net/socket.c:2939   __sys_recvmmsg net/socket.c:3018 [inline]   __do_sys_recvmmsg net/socket.c:3041 [inline]   __se_sys_recvmmsg net/socket.c:3034 [inline]   __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3034   do_syscall_x64 arch/x86/entry/common.c:52 [inline]   do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83  entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7faeb6363db9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 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 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffcc1997168 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007faeb6363db9 RDX: 0000000000000001 RSI: 0000000020000bc0 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000001c R10: 0000000000000122 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001","modified":"2026-09-15T09:02:56.912884072Z","published":"2024-05-30T16:15:14.030Z","upstream":["CVE-2024-36905"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-36905"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.94-1"}]}],"versions":["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~bpo11+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-36905.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.8.11-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-36905.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.8.11-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-36905.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:N/I:N/A:H"}]}