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: 6779 Comm: syz-executor668 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:ffffc90001657c48 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000010 RCX: ffffffff862d38d2 RDX: 0000000000000002 RSI: ffffffff87dce501 RDI: ffff88809f2887d0 RBP: ffff88809f2887c0 R08: 0000000000000001 R09: ffff888087c978e3 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880a762eb00 R14: ffffc90001657eb0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae700000(0063) knlGS:0000000009fbf840 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000020000000 CR3: 0000000094f94000 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_32_irqs_on+0x3f/0x60 arch/x86/entry/common.c:403 __do_fast_syscall_32 arch/x86/entry/common.c:448 [inline] do_fast_syscall_32+0x7f/0x120 arch/x86/entry/common.c:474 entry_SYSENTER_compat+0x6d/0x7c arch/x86/entry/entry_64_compat.S:138 RIP: 0023:0xf7fc7569 Code: Bad RIP value. RSP: 002b:00000000ffc683cc EFLAGS: 00000217 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000000000a0 RDI: 0000000000000000 RBP: 0000000000c10000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 9bcb6cee7b01ad92 ]--- 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:ffffc90001657c48 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000010 RCX: ffffffff862d38d2 RDX: 0000000000000002 RSI: ffffffff87dce501 RDI: ffff88809f2887d0 RBP: ffff88809f2887c0 R08: 0000000000000001 R09: ffff888087c978e3 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880a762eb00 R14: ffffc90001657eb0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae600000(0063) knlGS:0000000009fbf840 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00007f405623c6c0 CR3: 0000000094f94000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400