BUG: kernel NULL pointer dereference, address: 0000000000000134 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 89ae6067 P4D 89ae6067 PUD a3497067 PMD 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 9387 Comm: syz-fuzzer Not tainted 5.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:qlink_to_object mm/kasan/quarantine.c:137 [inline] RIP: 0010:qlink_free mm/kasan/quarantine.c:142 [inline] RIP: 0010:qlist_free_all+0x28/0x140 mm/kasan/quarantine.c:167 Code: d6 90 41 57 41 56 41 55 41 54 55 53 48 8b 1f 48 85 db 0f 84 08 01 00 00 48 89 f5 49 89 fd 48 85 ed 49 89 ee 0f 84 8b 00 00 00 <49> 63 86 34 01 00 00 4c 8b 23 48 29 c3 48 83 3d d3 df c4 07 00 0f RSP: 0018:ffffc900020e7728 EFLAGS: 00010246 RAX: ffffea0000000000 RBX: ffff888000000000 RCX: ffffea0000000007 RDX: 0000000000000000 RSI: ffffffff8133356a RDI: 0000000000000007 RBP: 0000000000000000 R08: ffff8880941dc2c0 R09: fffffbfff180eb8a R10: fffffbfff180eb89 R11: ffffffff8c075c4f R12: ffff888000000000 R13: ffffc900020e7760 R14: 0000000000000000 R15: 0000000000000286 FS: 000000c00007ce90(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000134 CR3: 0000000090aaa000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: quarantine_reduce+0x159/0x190 mm/kasan/quarantine.c:260 __kasan_kmalloc.constprop.0+0x97/0xd0 mm/kasan/common.c:496 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slab.c:3263 [inline] kmem_cache_alloc_node_trace+0x14b/0x790 mm/slab.c:3593 __do_kmalloc_node mm/slab.c:3615 [inline] __kmalloc_node_track_caller+0x38/0x60 mm/slab.c:3630 __kmalloc_reserve.isra.0+0x39/0xe0 net/core/skbuff.c:142 __alloc_skb+0xef/0x5a0 net/core/skbuff.c:210 alloc_skb_fclone include/linux/skbuff.h:1131 [inline] sk_stream_alloc_skb net/ipv4/tcp.c:876 [inline] sk_stream_alloc_skb+0x106/0xc70 net/ipv4/tcp.c:853 tcp_sendmsg_locked+0xcb0/0x3210 net/ipv4/tcp.c:1283 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1433 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 sock_write_iter+0x283/0x3c0 net/socket.c:1004 call_write_iter include/linux/fs.h:1901 [inline] new_sync_write+0x49c/0x700 fs/read_write.c:483 __vfs_write+0xc9/0x100 fs/read_write.c:496 vfs_write+0x262/0x5c0 fs/read_write.c:558 ksys_write+0x1e8/0x250 fs/read_write.c:611 do_syscall_64+0xf6/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4afb40 Code: 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 49 c7 c2 00 00 00 00 49 c7 c0 00 00 00 00 49 c7 c1 00 00 00 00 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 RSP: 002b:000000c00047b450 EFLAGS: 00000206 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000c00002e500 RCX: 00000000004afb40 RDX: 00000000000000f0 RSI: 000000c00000a3e0 RDI: 0000000000000003 RBP: 000000c00047b4a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 000000000000011e R13: 000000c00040a000 R14: 000000000000007f R15: ffffffffffffb9bc Modules linked in: CR2: 0000000000000134 ---[ end trace 6c0c3f7a2e50cbd3 ]--- RIP: 0010:qlink_to_object mm/kasan/quarantine.c:137 [inline] RIP: 0010:qlink_free mm/kasan/quarantine.c:142 [inline] RIP: 0010:qlist_free_all+0x28/0x140 mm/kasan/quarantine.c:167 Code: d6 90 41 57 41 56 41 55 41 54 55 53 48 8b 1f 48 85 db 0f 84 08 01 00 00 48 89 f5 49 89 fd 48 85 ed 49 89 ee 0f 84 8b 00 00 00 <49> 63 86 34 01 00 00 4c 8b 23 48 29 c3 48 83 3d d3 df c4 07 00 0f RSP: 0018:ffffc900020e7728 EFLAGS: 00010246 RAX: ffffea0000000000 RBX: ffff888000000000 RCX: ffffea0000000007 RDX: 0000000000000000 RSI: ffffffff8133356a RDI: 0000000000000007 RBP: 0000000000000000 R08: ffff8880941dc2c0 R09: fffffbfff180eb8a R10: fffffbfff180eb89 R11: ffffffff8c075c4f R12: ffff888000000000 R13: ffffc900020e7760 R14: 0000000000000000 R15: 0000000000000286 FS: 000000c00007ce90(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f09e2abd000 CR3: 0000000090aaa000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400