bisecting fixing commit since c98875d930e915d01e8c40c7d3c16f00b3c8abe1 building syzkaller on 53199d6e8aee5f0ebd3775d2b1c674f4e6e64e2b testing commit c98875d930e915d01e8c40c7d3c16f00b3c8abe1 with gcc (GCC) 8.4.1 20210217 kernel signature: 2384b2413b3e30009dac5642db10b433f0d691ed362df34bf90adec2c3731eaf run #0: crashed: general protection fault in skb_put run #1: crashed: general protection fault in skb_put run #2: crashed: general protection fault in skb_put run #3: crashed: general protection fault in skb_put run #4: crashed: general protection fault in skb_put run #5: crashed: general protection fault in skb_put run #6: crashed: general protection fault in skb_put run #7: crashed: general protection fault in skb_put run #8: crashed: general protection fault in skb_put run #9: crashed: general protection fault in skb_put run #10: crashed: general protection fault in skb_put run #11: crashed: general protection fault in skb_put run #12: crashed: general protection fault in skb_put run #13: crashed: general protection fault in skb_put run #14: crashed: general protection fault in skb_put run #15: crashed: general protection fault in corrupted run #16: crashed: general protection fault in skb_put run #17: crashed: general protection fault in skb_put run #18: crashed: general protection fault in skb_put run #19: crashed: general protection fault in skb_put testing current HEAD 6b7b0056defc6eb5c87bbe4690ccda547b2891aa testing commit 6b7b0056defc6eb5c87bbe4690ccda547b2891aa with gcc (GCC) 8.4.1 20210217 kernel signature: ca6fc1a19fb94ee248b89fff66ab43c8fe39ec78b9c68544890723d4c8b6df1e run #0: crashed: general protection fault in skb_put run #1: crashed: general protection fault in skb_put run #2: crashed: general protection fault in corrupted run #3: crashed: general protection fault in skb_put run #4: crashed: general protection fault in skb_put run #5: crashed: general protection fault in skb_put run #6: crashed: general protection fault in skb_put run #7: crashed: general protection fault in skb_put run #8: crashed: general protection fault in corrupted run #9: crashed: general protection fault in skb_put revisions tested: 2, total time: 23m40.371541169s (build: 16m14.651433504s, test: 6m43.754272118s) the crash still happens on HEAD commit msg: Linux 4.19.192 crash: general protection fault in skb_put RDX: 0000000020000100 RSI: 0000000000005412 RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000003 R14: 00000000004ae997 R15: 00007f49a0dcc6bc Bluetooth: Can't allocate mem for new packet general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 46 Comm: kworker/u4:2 Not tainted 4.19.192-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound flush_to_ldisc RIP: 0010:skb_put+0x28/0x1e0 net/core/skbuff.c:1706 Code: 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 55 4c 8d af c8 00 00 00 41 54 4c 89 ea 53 48 89 fb 48 c1 ea 03 48 83 ec 10 <0f> b6 14 02 4c 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 28 RSP: 0018:ffff8881f5197a88 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8881def5abdc RDX: 0000000000000019 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff8881f5197ab0 R08: ffffed103ed24733 R09: ffffed103ed24732 R10: ffffed103ed24732 R11: ffff8881f6923993 R12: ffff8881dfa444aa R13: 00000000000000c8 R14: ffff8881def5aa80 R15: ffff8881def5ab78 FS: 0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3bef472000 CR3: 000000000806d004 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_put_data include/linux/skbuff.h:2128 [inline] bcsp_unslip_one_byte drivers/bluetooth/hci_bcsp.c:451 [inline] bcsp_recv+0x9bb/0x1650 drivers/bluetooth/hci_bcsp.c:613 hci_uart_tty_receive+0x1d4/0x470 drivers/bluetooth/hci_ldisc.c:621 tty_ldisc_receive_buf+0x103/0x1c0 drivers/tty/tty_buffer.c:460 tty_port_default_receive_buf+0x5f/0x90 drivers/tty/tty_port.c:38 receive_buf drivers/tty/tty_buffer.c:476 [inline] flush_to_ldisc+0x1af/0x3a0 drivers/tty/tty_buffer.c:528 process_one_work+0x835/0x1670 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x34a/0x410 kernel/kthread.c:259 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 Modules linked in: general protection fault: 0000 [#2] PREEMPT SMP KASAN CPU: 0 PID: 2342 Comm: kworker/u4:4 Tainted: G D 4.19.192-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound flush_to_ldisc RIP: 0010:skb_put+0x28/0x1e0 net/core/skbuff.c:1706 Code: 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 55 4c 8d af c8 00 00 00 41 54 4c 89 ea 53 48 89 fb 48 c1 ea 03 48 83 ec 10 <0f> b6 14 02 4c 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 28 RSP: 0018:ffff8881eafbfa88 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8881e15debdc RDX: 0000000000000019 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff8881eafbfab0 R08: ffffed103ed24733 R09: ffffed103ed24732 R10: ffffed103ed24732 R11: ffff8881f6923993 R12: ffff8881dfa456aa R13: 00000000000000c8 R14: ffff8881e15dea80 R15: ffff8881e15deb78 FS: 0000000000000000(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c3248ad448 CR3: 000000000806d002 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_put_data include/linux/skbuff.h:2128 [inline] bcsp_unslip_one_byte drivers/bluetooth/hci_bcsp.c:451 [inline] bcsp_recv+0x9bb/0x1650 drivers/bluetooth/hci_bcsp.c:613 hci_uart_tty_receive+0x1d4/0x470 drivers/bluetooth/hci_ldisc.c:621 tty_ldisc_receive_buf+0x103/0x1c0 drivers/tty/tty_buffer.c:460 tty_port_default_receive_buf+0x5f/0x90 drivers/tty/tty_port.c:38 receive_buf drivers/tty/tty_buffer.c:476 [inline] flush_to_ldisc+0x1af/0x3a0 drivers/tty/tty_buffer.c:528 process_one_work+0x835/0x1670 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x34a/0x410 kernel/kthread.c:259 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 Modules linked in: general protection fault: 0000 [#3] PREEMPT SMP KASAN ---[ end trace 9ab67218ababc7bd ]--- CPU: 1 PID: 2705 Comm: kworker/u4:5 Tainted: G D 4.19.192-syzkaller #0 RIP: 0010:skb_put+0x28/0x1e0 net/core/skbuff.c:1706 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound flush_to_ldisc RIP: 0010:skb_put+0x28/0x1e0 net/core/skbuff.c:1706 Code: 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 55 4c 8d af c8 00 00 00 41 54 4c 89 ea 53 48 89 fb 48 c1 ea 03 48 83 ec 10 <0f> b6 14 02 4c 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 28 RSP: 0018:ffff8881e7df7a88 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8881de99cddc RDX: 0000000000000019 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff8881e7df7ab0 R08: ffffed103ed24733 R09: ffffed103ed24732 R10: ffffed103ed24732 R11: ffff8881f6923993 R12: ffff8881dfa44daa Code: 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 55 4c 8d af c8 00 00 00 41 54 4c 89 ea 53 48 89 fb 48 c1 ea 03 48 83 ec 10 <0f> b6 14 02 4c 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 28 R13: 00000000000000c8 R14: ffff8881de99cc80 R15: ffff8881de99cd78 FS: 0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3bef3f4000 CR3: 000000000806d003 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_put_data include/linux/skbuff.h:2128 [inline] bcsp_unslip_one_byte drivers/bluetooth/hci_bcsp.c:451 [inline] bcsp_recv+0x9bb/0x1650 drivers/bluetooth/hci_bcsp.c:613 RSP: 0018:ffff8881f5197a88 EFLAGS: 00010286 Bluetooth: Can't allocate mem for new packet RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8881def5abdc hci_uart_tty_receive+0x1d4/0x470 drivers/bluetooth/hci_ldisc.c:621 tty_ldisc_receive_buf+0x103/0x1c0 drivers/tty/tty_buffer.c:460 tty_port_default_receive_buf+0x5f/0x90 drivers/tty/tty_port.c:38 receive_buf drivers/tty/tty_buffer.c:476 [inline] flush_to_ldisc+0x1af/0x3a0 drivers/tty/tty_buffer.c:528 process_one_work+0x835/0x1670 kernel/workqueue.c:2152 RDX: 0000000000000019 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff8881f5197ab0 R08: ffffed103ed24733 R09: ffffed103ed24732 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x34a/0x410 kernel/kthread.c:259 R10: ffffed103ed24732 R11: ffff8881f6923993 R12: ffff8881dfa444aa R13: 00000000000000c8 R14: ffff8881def5aa80 R15: ffff8881def5ab78 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 Modules linked in: ---[ end trace 9ab67218ababc7be ]--- Bluetooth: Can't allocate mem for new packet RIP: 0010:skb_put+0x28/0x1e0 net/core/skbuff.c:1706 FS: 0000000000000000(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000 Code: 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 55 4c 8d af c8 00 00 00 41 54 4c 89 ea 53 48 89 fb 48 c1 ea 03 48 83 ec 10 <0f> b6 14 02 4c 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 28 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 RSP: 0018:ffff8881f5197a88 EFLAGS: 00010286 CR2: 00007f214751bf88 CR3: 000000000806d003 CR4: 00000000001606f0 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8881def5abdc DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 RDX: 0000000000000019 RSI: 0000000000000001 RDI: 0000000000000000