syzbot has found a reproducer for the following issue on: HEAD commit: 2d3d8c7643a5 Add linux-next specific files for 20220203 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=14c0c8dc700000 kernel config: https://syzkaller.appspot.com/x/.config?x=27a9abf2c11167c7 dashboard link: https://syzkaller.appspot.com/bug?extid=2b3f18414c37b42dcc94 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14635480700000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10eb2d14700000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2b3f18414c37b42dcc94@xxxxxxxxxxxxxxxxxxxxxxxxx BTRFS info (device loop0): disk space caching is enabled BTRFS info (device loop0): has skinny extents BTRFS info (device loop0): enabling ssd optimizations general protection fault, probably for non-canonical address 0xdffffc000000002f: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000178-0x000000000000017f] CPU: 0 PID: 3586 Comm: syz-executor095 Not tainted 5.17.0-rc2-next-20220203-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:blk_throtl_bio block/blk-throttle.h:175 [inline] RIP: 0010:submit_bio_checks+0x7c0/0x1bf0 block/blk-core.c:765 Code: 08 3c 03 0f 8e 4a 11 00 00 48 b8 00 00 00 00 00 fc ff df 44 8b 6d 10 41 83 e5 01 4a 8d bc 2b 7c 01 00 00 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 09 11 00 00 RSP: 0018:ffffc9000293f278 EFLAGS: 00010203 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 000000000000002f RSI: ffffffff83d5d9de RDI: 000000000000017d RBP: ffff888014fbd300 R08: ffffffff8a044f00 R09: 0000000000000000 R10: ffffffff83d5d9d0 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000001 R14: 00000000fffffffe R15: ffff88801a2be93c FS: 0000555555975300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9789f79668 CR3: 00000000145d1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __submit_bio+0xaf/0x360 block/blk-core.c:802 __submit_bio_noacct_mq block/blk-core.c:881 [inline] submit_bio_noacct block/blk-core.c:907 [inline] submit_bio_noacct+0x6c9/0x8a0 block/blk-core.c:896 submit_bio block/blk-core.c:968 [inline] submit_bio+0x1ea/0x430 block/blk-core.c:926 write_dev_flush fs/btrfs/disk-io.c:4243 [inline] barrier_all_devices fs/btrfs/disk-io.c:4293 [inline] write_all_supers+0x3038/0x4440 fs/btrfs/disk-io.c:4388 btrfs_commit_transaction+0x1be3/0x3180 fs/btrfs/transaction.c:2362 btrfs_commit_super+0xc1/0x100 fs/btrfs/disk-io.c:4562 close_ctree+0x314/0xccc fs/btrfs/disk-io.c:4671 btrfs_fill_super fs/btrfs/super.c:1400 [inline] btrfs_mount_root.cold+0xb1/0x162 fs/btrfs/super.c:1744 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1497 fc_mount fs/namespace.c:1016 [inline] vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1046 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1033 btrfs_mount+0x234/0xa60 fs/btrfs/super.c:1804 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1497 do_new_mount fs/namespace.c:3012 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3342 do_mount fs/namespace.c:3355 [inline] __do_sys_mount fs/namespace.c:3563 [inline] __se_sys_mount fs/namespace.c:3540 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3540 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7ff53f71fd8a Code: 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffeaf8661f8 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007ffeaf866250 RCX: 00007ff53f71fd8a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffeaf866210 RBP: 00007ffeaf866210 R08: 00007ffeaf866250 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000282 R12: 0000000020000f50 R13: 0000000000000003 R14: 0000000000000004 R15: 000000000000008e </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:blk_throtl_bio block/blk-throttle.h:175 [inline] RIP: 0010:submit_bio_checks+0x7c0/0x1bf0 block/blk-core.c:765 Code: 08 3c 03 0f 8e 4a 11 00 00 48 b8 00 00 00 00 00 fc ff df 44 8b 6d 10 41 83 e5 01 4a 8d bc 2b 7c 01 00 00 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 09 11 00 00 RSP: 0018:ffffc9000293f278 EFLAGS: 00010203 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 000000000000002f RSI: ffffffff83d5d9de RDI: 000000000000017d RBP: ffff888014fbd300 R08: ffffffff8a044f00 R09: 0000000000000000 R10: ffffffff83d5d9d0 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000001 R14: 00000000fffffffe R15: ffff88801a2be93c FS: 0000555555975300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fab1d1bfe28 CR3: 00000000145d1000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 08 3c 03 or %bh,(%rbx,%rax,1) 3: 0f 8e 4a 11 00 00 jle 0x1153 9: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 10: fc ff df 13: 44 8b 6d 10 mov 0x10(%rbp),%r13d 17: 41 83 e5 01 and $0x1,%r13d 1b: 4a 8d bc 2b 7c 01 00 lea 0x17c(%rbx,%r13,1),%rdi 22: 00 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax <-- trapping instruction 2e: 48 89 fa mov %rdi,%rdx 31: 83 e2 07 and $0x7,%edx 34: 38 d0 cmp %dl,%al 36: 7f 08 jg 0x40 38: 84 c0 test %al,%al 3a: 0f 85 09 11 00 00 jne 0x1149
