bisecting fixing commit since 63623fd44972d1ed2bfb6e0fb631dfcf547fd1e7 building syzkaller on c88c7b75a4e022b758f4b0f1bf3db8ebb2fb25e6 testing commit 63623fd44972d1ed2bfb6e0fb631dfcf547fd1e7 with gcc (GCC) 8.1.0 kernel signature: 81a911d6a17f6ef902b5cba90e986ca3b4a5cb441df9bf737cb61befa80218e7 all runs: crashed: general protection fault in j1939_netdev_start testing current HEAD 15a2bc4dbb9cfed1c661a657fcb10798150b7598 testing commit 15a2bc4dbb9cfed1c661a657fcb10798150b7598 with gcc (GCC) 8.1.0 kernel signature: e76180803dfce3b972cb4fba9132d7b7de5a28a310d39038229bd7bcbc1e5d78 all runs: crashed: general protection fault in j1939_netdev_start revisions tested: 2, total time: 20m41.566505211s (build: 12m59.036014534s, test: 6m45.236917386s) the crash still happens on HEAD commit msg: Merge branch 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace crash: general protection fault in j1939_netdev_start general protection fault, probably for non-canonical address 0xdffffc0000000c05: 0000 [#1] PREEMPT SMP KASAN KASAN: probably user-memory-access in range [0x0000000000006028-0x000000000000602f] CPU: 0 PID: 9568 Comm: syz-executor.2 Not tainted 5.7.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:j1939_priv_set net/can/j1939/main.c:145 [inline] RIP: 0010:j1939_netdev_start+0x322/0x5b0 net/can/j1939/main.c:280 Code: 03 80 3c 02 00 0f 85 7a 02 00 00 4c 8b bb a0 05 00 00 48 ba 00 00 00 00 00 fc ff df 49 8d bf 28 60 00 00 48 89 f9 48 c1 e9 03 <80> 3c 11 00 0f 85 47 02 00 00 4d 89 a7 28 60 00 00 48 c7 c7 60 51 RSP: 0018:ffffc9000c7ffcb0 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: ffff8880a6d44000 RCX: 0000000000000c05 RDX: dffffc0000000000 RSI: ffffffff89e35178 RDI: 0000000000006028 RBP: ffffc9000c7ffce8 R08: 0000000000000004 R09: fffff520018fff83 R10: 0000000000000003 R11: fffff520018fff83 R12: ffff8880a6e6c000 R13: ffff8880a6d44568 R14: ffff8880a6e6c050 R15: 0000000000000000 FS: 00007fe78be67700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc1caf59db8 CR3: 00000000883e6000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: j1939_sk_bind+0x5e4/0x910 net/can/j1939/socket.c:469 __sys_bind+0x1e1/0x230 net/socket.c:1657 __do_sys_bind net/socket.c:1668 [inline] __se_sys_bind net/socket.c:1666 [inline] __x64_sys_bind+0x6e/0xb0 net/socket.c:1666 do_syscall_64+0xca/0x630 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45c479 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fe78be66c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 00007fe78be676d4 RCX: 000000000045c479 RDX: 0000000000000018 RSI: 0000000020000040 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000030 R14: 00000000004c291e R15: 000000000076bf2c Modules linked in: ---[ end trace 82ba28840f14f0ac ]--- RIP: 0010:j1939_priv_set net/can/j1939/main.c:145 [inline] RIP: 0010:j1939_netdev_start+0x322/0x5b0 net/can/j1939/main.c:280 Code: 03 80 3c 02 00 0f 85 7a 02 00 00 4c 8b bb a0 05 00 00 48 ba 00 00 00 00 00 fc ff df 49 8d bf 28 60 00 00 48 89 f9 48 c1 e9 03 <80> 3c 11 00 0f 85 47 02 00 00 4d 89 a7 28 60 00 00 48 c7 c7 60 51 RSP: 0018:ffffc9000c7ffcb0 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: ffff8880a6d44000 RCX: 0000000000000c05 RDX: dffffc0000000000 RSI: ffffffff89e35178 RDI: 0000000000006028 RBP: ffffc9000c7ffce8 R08: 0000000000000004 R09: fffff520018fff83 R10: 0000000000000003 R11: fffff520018fff83 R12: ffff8880a6e6c000 R13: ffff8880a6d44568 R14: ffff8880a6e6c050 R15: 0000000000000000 FS: 00007fe78be67700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc1caf59db8 CR3: 00000000883e6000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400