capability: warning: `syz-executor2' uses 32-bit capabilities (legacy support in use) print_req_error: I/O error, dev loop4, sector 128 ====================================================== WARNING: possible circular locking dependency detected 4.14.0-rc3+ #112 Not tainted ------------------------------------------------------ loop0/4469 is trying to acquire lock: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_lock include/linux/fs.h:712 [inline] (&sb->s_type->i_mutex_key#9){++++}, at: [] shmem_fallocate+0x161/0x1160 mm/shmem.c:2841 but now in release context of a crosslock acquired at the following: ((complete)&ret.event){+.+.}, at: [] submit_bio_wait+0x15e/0x200 block/bio.c:953 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 ((complete)&ret.event){+.+.}: check_prevs_add kernel/locking/lockdep.c:2020 [inline] validate_chain kernel/locking/lockdep.c:2469 [inline] __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 complete_acquire include/linux/completion.h:39 [inline] __wait_for_common kernel/sched/completion.c:108 [inline] wait_for_common_io kernel/sched/completion.c:128 [inline] wait_for_completion_io+0xcb/0x7b0 kernel/sched/completion.c:176 submit_bio_wait+0x15e/0x200 block/bio.c:953 blkdev_issue_zeroout+0x13c/0x1d0 block/blk-lib.c:370 sb_issue_zeroout include/linux/blkdev.h:1368 [inline] ext4_init_inode_table+0x4fd/0xdb1 fs/ext4/ialloc.c:1447 ext4_run_li_request fs/ext4/super.c:2866 [inline] ext4_lazyinit_thread+0x808/0xd30 fs/ext4/super.c:2960 kthread+0x39c/0x470 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 -> #3 (&meta_group_info[i]->alloc_sem){++++}: check_prevs_add kernel/locking/lockdep.c:2020 [inline] validate_chain kernel/locking/lockdep.c:2469 [inline] __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 down_read+0x96/0x150 kernel/locking/rwsem.c:23 __ext4_new_inode+0x26dc/0x4f00 fs/ext4/ialloc.c:1056 ext4_symlink+0x2d9/0xae0 fs/ext4/namei.c:3118 vfs_symlink+0x323/0x560 fs/namei.c:4115 SYSC_symlinkat fs/namei.c:4142 [inline] SyS_symlinkat fs/namei.c:4122 [inline] SYSC_symlink fs/namei.c:4155 [inline] SyS_symlink+0x134/0x200 fs/namei.c:4153 entry_SYSCALL_64_fastpath+0x1f/0xbe -> #2 (jbd2_handle){++++}: check_prevs_add kernel/locking/lockdep.c:2020 [inline] validate_chain kernel/locking/lockdep.c:2469 [inline] __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 start_this_handle+0x4b8/0x1080 fs/jbd2/transaction.c:390 jbd2__journal_start+0x389/0x9f0 fs/jbd2/transaction.c:444 __ext4_journal_start_sb+0x15f/0x550 fs/ext4/ext4_jbd2.c:80 __ext4_journal_start fs/ext4/ext4_jbd2.h:314 [inline] ext4_dirty_inode+0x56/0xa0 fs/ext4/inode.c:5859 __mark_inode_dirty+0x912/0x1170 fs/fs-writeback.c:2096 generic_update_time+0x1b2/0x270 fs/inode.c:1649 update_time fs/inode.c:1665 [inline] touch_atime+0x26d/0x2f0 fs/inode.c:1737 file_accessed include/linux/fs.h:2061 [inline] ext4_file_mmap+0x161/0x1b0 fs/ext4/file.c:352 call_mmap include/linux/fs.h:1775 [inline] mmap_region+0xa99/0x15a0 mm/mmap.c:1690 do_mmap+0x6a1/0xd50 mm/mmap.c:1468 do_mmap_pgoff include/linux/mm.h:2150 [inline] vm_mmap_pgoff+0x1de/0x280 mm/util.c:333 SYSC_mmap_pgoff mm/mmap.c:1518 [inline] SyS_mmap_pgoff+0x462/0x5f0 mm/mmap.c:1476 SYSC_mmap arch/x86/kernel/sys_x86_64.c:99 [inline] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:90 entry_SYSCALL_64_fastpath+0x1f/0xbe -> #1 (&mm->mmap_sem){++++}: check_prevs_add kernel/locking/lockdep.c:2020 [inline] validate_chain kernel/locking/lockdep.c:2469 [inline] __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 __might_fault+0x13a/0x1d0 mm/memory.c:4502 _copy_to_user+0x2c/0xc0 lib/usercopy.c:24 copy_to_user include/linux/uaccess.h:154 [inline] filldir+0x1a7/0x320 fs/readdir.c:196 dir_emit_dot include/linux/fs.h:3339 [inline] dir_emit_dots include/linux/fs.h:3350 [inline] dcache_readdir+0x12d/0x5e0 fs/libfs.c:192 iterate_dir+0x4b2/0x5d0 fs/readdir.c:51 SYSC_getdents fs/readdir.c:231 [inline] SyS_getdents+0x225/0x450 fs/readdir.c:212 entry_SYSCALL_64_fastpath+0x1f/0xbe -> #0 (&sb->s_type->i_mutex_key#9){++++}: down_write+0x87/0x120 kernel/locking/rwsem.c:53 inode_lock include/linux/fs.h:712 [inline] shmem_fallocate+0x161/0x1160 mm/shmem.c:2841 lo_discard drivers/block/loop.c:434 [inline] do_req_filebacked drivers/block/loop.c:570 [inline] loop_handle_cmd drivers/block/loop.c:1705 [inline] loop_queue_work+0x46f/0x3900 drivers/block/loop.c:1719 kthread_worker_fn+0x32b/0x980 kernel/kthread.c:635 loop_kthread_worker_fn+0x51/0x60 drivers/block/loop.c:836 other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#9 --> &meta_group_info[i]->alloc_sem --> (complete)&ret.event Possible unsafe locking scenario by crosslock: CPU0 CPU1 ---- ---- lock(&meta_group_info[i]->alloc_sem); lock((complete)&ret.event); lock(&sb->s_type->i_mutex_key#9); unlock((complete)&ret.event); *** DEADLOCK *** 1 lock held by loop0/4469: #0: (&x->wait#14){..-.}, at: [] complete+0x18/0x80 kernel/sched/completion.c:34 stack backtrace: CPU: 0 PID: 4469 Comm: loop0 Not tainted 4.14.0-rc3+ #112 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_circular_bug+0x503/0x710 kernel/locking/lockdep.c:1259 check_prev_add+0x865/0x1520 kernel/locking/lockdep.c:1894 commit_xhlock kernel/locking/lockdep.c:5015 [inline] commit_xhlocks kernel/locking/lockdep.c:5059 [inline] lock_commit_crosslock+0xe59/0x1d00 kernel/locking/lockdep.c:5098 complete_release_commit include/linux/completion.h:49 [inline] complete+0x24/0x80 kernel/sched/completion.c:39 submit_bio_wait_endio+0x9c/0xd0 block/bio.c:930 bio_endio+0x2f8/0x8d0 block/bio.c:1843 req_bio_endio block/blk-core.c:204 [inline] blk_update_request+0x2a6/0xe20 block/blk-core.c:2746 blk_mq_end_request+0x54/0x120 block/blk-mq.c:509 lo_complete_rq+0xbe/0x1f0 drivers/block/loop.c:463 __blk_mq_complete_request+0x38f/0x6c0 block/blk-mq.c:550 blk_mq_complete_request+0x4f/0x60 block/blk-mq.c:570 loop_handle_cmd drivers/block/loop.c:1710 [inline] loop_queue_work+0x26b/0x3900 drivers/block/loop.c:1719 kthread_worker_fn+0x32b/0x980 kernel/kthread.c:635 loop_kthread_worker_fn+0x51/0x60 drivers/block/loop.c:836 kthread+0x39c/0x470 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 device lo entered promiscuous mode device lo left promiscuous mode SELinux: unrecognized netlink message: protocol=0 nlmsg_type=61159 sclass=netlink_route_socket pig=5093 comm=syz-executor5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=61159 sclass=netlink_route_socket pig=5101 comm=syz-executor5 QAT: Invalid ioctl QAT: Invalid ioctl kvm: pic: non byte write QAT: Invalid ioctl QAT: Invalid ioctl *** Guest State *** CR0: actual=0x0000000080000031, shadow=0x0000000060000010, gh_mask=fffffffffffffff7 CR4: actual=0x0000000000002051, shadow=0x0000000000000000, gh_mask=ffffffffffffe871 CR3 = 0x00000000fffbc000 RSP = 0x000000000000fffa RIP = 0x000000000000c000 RFLAGS=0x00033000 DR7 = 0x0000000000000400 Sysenter RSP=0000000000000000 CS:RIP=0000:0000000000000000 CS: sel=0x320f, attr=0x000f3, limit=0x0000ffff, base=0x00000000000320f0 DS: sel=0x0000, attr=0x000f3, limit=0x0000ffff, base=0x0000000000000000 SS: sel=0x0000, attr=0x000f3, limit=0x0000ffff, base=0x0000000000000000 ES: sel=0x0000, attr=0x000f3, limit=0x0000ffff, base=0x0000000000000000 FS: sel=0x0000, attr=0x000f3, limit=0x0000ffff, base=0x0000000000000000 GS: sel=0x0000, attr=0x000f3, limit=0x0000ffff, base=0x0000000000000000 GDTR: limit=0x0000ffff, base=0x0000000000000000 LDTR: sel=0x0000, attr=0x00082, limit=0x0000ffff, base=0x0000000000000000 IDTR: limit=0x0000ffff, base=0x0000000000000000 TR: sel=0x0000, attr=0x0008b, limit=0x00002088, base=0x0000000000000000 EFER = 0x0000000000000000 PAT = 0x0007040600070406 DebugCtl = 0x0000000000000000 DebugExceptions = 0x0000000000000000 Interruptibility = 00000000 ActivityState = 00000000 *** Host State *** RIP = 0xffffffff811ba093 RSP = 0xffff8801c6c674c8 CS=0010 SS=0018 DS=0000 ES=0000 FS=0000 GS=0000 TR=0040 FSBase=00007fd1b9c3a700 GSBase=ffff8801db200000 TRBase=ffff8801db3231c0 GDTBase=ffffffffff576000 IDTBase=ffffffffff57b000 CR0=0000000080050033 CR3=00000001cb7a7000 CR4=00000000001426f0 Sysenter RSP=0000000000000000 CS:RIP=0010:ffffffff84d4d330 EFER = 0x0000000000000d01 PAT = 0x0000000000000000 *** Control State *** PinBased=0000003f CPUBased=b6a1edfa SecondaryExec=00000043 EntryControls=0000d1ff ExitControls=0023efff ExceptionBitmap=ffffbfff PFECmask=00000000 PFECmatch=00000000 VMEntry: intr_info=00000000 errcode=00000000 ilen=00000000 VMExit: intr_info=00000000 errcode=00000000 ilen=00000003 reason=80000021 qualification=0000000000000000 IDTVectoring: info=00000000 errcode=00000000 TSC Offset = 0xffffffda1ebb413f TPR Threshold = 0x00 EPT pointer = 0x00000001caf9c01e capability: warning: `syz-executor4' uses deprecated v2 capabilities in a way that may be insecure ================================================================== BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:673 [inline] BUG: KASAN: use-after-free in enqueue_timer kernel/time/timer.c:520 [inline] BUG: KASAN: use-after-free in __internal_add_timer+0x275/0x2d0 kernel/time/timer.c:531 Write of size 8 at addr ffff8801ca1ebd48 by task syz-executor7/5180 CPU: 0 PID: 5180 Comm: syz-executor7 Not tainted 4.14.0-rc3+ #112 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:435 hlist_add_head include/linux/list.h:673 [inline] enqueue_timer kernel/time/timer.c:520 [inline] __internal_add_timer+0x275/0x2d0 kernel/time/timer.c:531 internal_add_timer kernel/time/timer.c:573 [inline] __mod_timer kernel/time/timer.c:1024 [inline] mod_timer+0x622/0x15b0 kernel/time/timer.c:1071 tun_flow_init drivers/net/tun.c:1098 [inline] tun_set_iff drivers/net/tun.c:2058 [inline] __tun_chr_ioctl+0x1b23/0x3d20 drivers/net/tun.c:2276 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2521 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x4520a9 RSP: 002b:00007f83222ddc08 EFLAGS: 00000216 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 00000000004520a9 RDX: 0000000020574000 RSI: 00000000400454ca RDI: 000000000000001d RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000000000 R13: 0000000000a6f7ef R14: 00007f83222de9c0 R15: 0000000000000000 Allocated by task 5191: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 __do_kmalloc_node mm/slab.c:3689 [inline] __kmalloc_node+0x47/0x70 mm/slab.c:3696 kmalloc_node include/linux/slab.h:535 [inline] kvmalloc_node+0x64/0xd0 mm/util.c:397 kvmalloc include/linux/mm.h:529 [inline] kvzalloc include/linux/mm.h:537 [inline] alloc_netdev_mqs+0x16e/0xed0 net/core/dev.c:8023 tun_set_iff drivers/net/tun.c:2022 [inline] __tun_chr_ioctl+0x12be/0x3d20 drivers/net/tun.c:2276 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2521 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 5191: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xca/0x250 mm/slab.c:3820 kvfree+0x36/0x60 mm/util.c:416 netdev_freemem net/core/dev.c:7975 [inline] free_netdev+0x2cf/0x360 net/core/dev.c:8137 tun_set_iff drivers/net/tun.c:2105 [inline] __tun_chr_ioctl+0x2cf6/0x3d20 drivers/net/tun.c:2276 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2521 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xbe The buggy address belongs to the object at ffff8801ca1e8940 which belongs to the cache kmalloc-16384 of size 16384 The buggy address is located 13320 bytes inside of 16384-byte region [ffff8801ca1e8940, ffff8801ca1ec940) The buggy address belongs to the page: page:ffffea0007287a00 count:1 mapcount:0 mapping:ffff8801ca1e8940 index:0x0 compound_mapcount: 0 flags: 0x200000000008100(slab|head) raw: 0200000000008100 ffff8801ca1e8940 0000000000000000 0000000100000001 raw: ffffea00065fb820 ffffea0007278020 ffff8801dac02200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801ca1ebc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801ca1ebc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801ca1ebd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801ca1ebd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801ca1ebe00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================