Hello, syzbot found the following issue on: HEAD commit: ae074e2b2fd4 sfc: check for zero length in EF10 RX prefix git tree: net console+strace: https://syzkaller.appspot.com/x/log.txt?x=17d9e78fa80000 kernel config: https://syzkaller.appspot.com/x/.config?x=634e05b4025da9da dashboard link: https://syzkaller.appspot.com/bug?extid=d3ccfb78a0dc16ffebe3 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13075977a80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1012d447a80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/36dca89ab8e3/disk-ae074e2b.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/935bb2b8e325/vmlinux-ae074e2b.xz kernel image: https://storage.googleapis.com/syzbot-assets/d5ab72169cc9/bzImage-ae074e2b.xz The issue was bisected to: commit 94d9ba9f9888b748d4abd2aa1547af56ae85f772 Author: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Date: Wed Aug 9 23:49:33 2023 +0000 Bluetooth: hci_sync: Fix UAF in hci_disconnect_all_sync bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10a8c6bfa80000 final oops: https://syzkaller.appspot.com/x/report.txt?x=12a8c6bfa80000 console output: https://syzkaller.appspot.com/x/log.txt?x=14a8c6bfa80000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d3ccfb78a0dc16ffebe3@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 94d9ba9f9888 ("Bluetooth: hci_sync: Fix UAF in hci_disconnect_all_sync") general protection fault, probably for non-canonical address 0xdffffc0000000026: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000130-0x0000000000000137] CPU: 0 PID: 918 Comm: kworker/0:2 Not tainted 6.5.0-syzkaller-04011-gae074e2b2fd4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: events l2cap_info_timeout RIP: 0010:__lock_acquire+0x109/0x5de0 kernel/locking/lockdep.c:5012 Code: 45 85 c9 0f 84 cc 0e 00 00 44 8b 05 a1 14 23 0b 45 85 c0 0f 84 be 0d 00 00 48 ba 00 00 00 00 00 fc ff df 4c 89 d1 48 c1 e9 03 <80> 3c 11 00 0f 85 e8 40 00 00 49 81 3a a0 a9 3e 90 0f 84 96 0d 00 RSP: 0018:ffffc90004c8f8e8 EFLAGS: 00010002 RAX: ffff8880206d8000 RBX: 1ffff92000991f4d RCX: 0000000000000026 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000130 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000130 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0da069df50 CR3: 000000007a80d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3505 lock_sock include/net/sock.h:1722 [inline] l2cap_sock_ready_cb+0x41/0x160 net/bluetooth/l2cap_sock.c:1630 l2cap_chan_ready net/bluetooth/l2cap_core.c:1365 [inline] l2cap_conn_start+0x15c/0xa40 net/bluetooth/l2cap_core.c:1640 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__lock_acquire+0x109/0x5de0 kernel/locking/lockdep.c:5012 Code: 45 85 c9 0f 84 cc 0e 00 00 44 8b 05 a1 14 23 0b 45 85 c0 0f 84 be 0d 00 00 48 ba 00 00 00 00 00 fc ff df 4c 89 d1 48 c1 e9 03 <80> 3c 11 00 0f 85 e8 40 00 00 49 81 3a a0 a9 3e 90 0f 84 96 0d 00 RSP: 0018:ffffc90004c8f8e8 EFLAGS: 00010002 RAX: ffff8880206d8000 RBX: 1ffff92000991f4d RCX: 0000000000000026 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000130 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000130 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0da069df50 CR3: 000000007a80d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 45 85 c9 test %r9d,%r9d 3: 0f 84 cc 0e 00 00 je 0xed5 9: 44 8b 05 a1 14 23 0b mov 0xb2314a1(%rip),%r8d # 0xb2314b1 10: 45 85 c0 test %r8d,%r8d 13: 0f 84 be 0d 00 00 je 0xdd7 19: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx 20: fc ff df 23: 4c 89 d1 mov %r10,%rcx 26: 48 c1 e9 03 shr $0x3,%rcx * 2a: 80 3c 11 00 cmpb $0x0,(%rcx,%rdx,1) <-- trapping instruction 2e: 0f 85 e8 40 00 00 jne 0x411c 34: 49 81 3a a0 a9 3e 90 cmpq $0xffffffff903ea9a0,(%r10) 3b: 0f .byte 0xf 3c: 84 .byte 0x84 3d: 96 xchg %eax,%esi 3e: 0d .byte 0xd --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
