general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 1 PID: 6812 Comm: syz-executor171 Not tainted 5.8.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:qrtr_endpoint_post+0x92/0x1010 net/qrtr/qrtr.c:440 Code: 44 89 e6 e8 80 51 50 fe 48 85 c0 48 89 c5 0f 84 c4 0e 00 00 e8 ef 6b 96 f9 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 04 02 48 89 da 83 e2 07 38 d0 7f 08 84 c0 0f 85 4a 0d 00 00 RSP: 0018:ffffc90001277c60 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000010 RCX: ffffffff862d38d2 RDX: 0000000000000002 RSI: ffffffff87dce501 RDI: ffff888091a40e50 RBP: ffff888091a40e40 R08: 0000000000000001 R09: ffff8880865698e3 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888097eb9f00 R14: ffffc90001277ec8 R15: 0000000000000000 FS: 00000000009a7880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004551b0 CR3: 000000008d4a6000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: qrtr_tun_write_iter+0xf5/0x180 net/qrtr/tun.c:92 call_write_iter include/linux/fs.h:1907 [inline] new_sync_write+0x422/0x650 fs/read_write.c:484 __vfs_write+0xc9/0x100 fs/read_write.c:497 vfs_write+0x268/0x5d0 fs/read_write.c:559 ksys_write+0x12d/0x250 fs/read_write.c:612 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x440249 Code: Bad RIP value. RSP: 002b:00007ffc183d4298 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ffc183d42a0 RCX: 0000000000440249 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00000000006ca018 R08: 000000000000000f R09: 65732f636f72702f R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b30 R13: 0000000000401bc0 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 2fdacdf0f2b20f4e ]--- RIP: 0010:qrtr_endpoint_post+0x92/0x1010 net/qrtr/qrtr.c:440 Code: 44 89 e6 e8 80 51 50 fe 48 85 c0 48 89 c5 0f 84 c4 0e 00 00 e8 ef 6b 96 f9 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 04 02 48 89 da 83 e2 07 38 d0 7f 08 84 c0 0f 85 4a 0d 00 00 RSP: 0018:ffffc90001277c60 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000010 RCX: ffffffff862d38d2 RDX: 0000000000000002 RSI: ffffffff87dce501 RDI: ffff888091a40e50 RBP: ffff888091a40e40 R08: 0000000000000001 R09: ffff8880865698e3 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888097eb9f00 R14: ffffc90001277ec8 R15: 0000000000000000 FS: 00000000009a7880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004551b0 CR3: 000000008d4a6000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400