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TCP recvmsg seq # bug 2: copied 898E7F1E, seq 898E7EE6, rcvnxt 898E7EE7, fl 40
WARNING: CPU: 0 PID: 5562 at net/ipv4/tcp.c:2647 tcp_recvmsg_locked+0xad1/0x2780 net/ipv4/tcp.c:2647
Modules linked in:
CPU: 0 UID: 0 PID: 5562 Comm: syz-executor821 Not tainted 6.12.0-rc1-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:tcp_recvmsg_locked+0xad1/0x2780 net/ipv4/tcp.c:2647
Code: 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 b3 1b 00 00 48 8b 04 24 89 da 48 c7 c7 40 f8 a7 8c 44 8b 44 24 30 8b 30 e8 e0 f9 c5 f7 90 <0f> 0b 90 90 e9 1c fa ff ff e8 31 11 05 f8 49 8d 5f 60 be 08 00 00
RSP: 0018:ffffc90004bb7408 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 00000000898e7ee6 RCX: ffffffff814e7329
RDX: ffff88802c180000 RSI: ffffffff814e7336 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff88802cefb2f0 R14: ffff88802cefb324 R15: ffff88802cefb318
FS:  00005555608e6380(0000) GS:ffff88806a600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000cf3d CR3: 0000000027be4000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 receive_fallback_to_copy net/ipv4/tcp.c:1890 [inline]
 tcp_zerocopy_receive+0x1483/0x2620 net/ipv4/tcp.c:2122
 do_tcp_getsockopt+0x1803/0x2970 net/ipv4/tcp.c:4582
 tcp_getsockopt net/ipv4/tcp.c:4672 [inline]
 tcp_getsockopt+0xdf/0x100 net/ipv4/tcp.c:4663
 do_sock_getsockopt+0x3fe/0x800 net/socket.c:2391
 __sys_getsockopt+0x1a1/0x270 net/socket.c:2420
 __do_sys_getsockopt net/socket.c:2430 [inline]
 __se_sys_getsockopt net/socket.c:2427 [inline]
 __x64_sys_getsockopt+0xbd/0x160 net/socket.c:2427
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fda22922079
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 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff1ea265c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fda22922079
RDX: 0000000000000023 RSI: 0000000000000006 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000200004c0 R09: 0000000000000006
R10: 0000000020000380 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
 </TASK>