Hello, syzbot found the following crash on: HEAD commit: 39884604 mptcp: fix NULL ptr dereference in MP_JOIN error .. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=1322a9ce100000 kernel config: https://syzkaller.appspot.com/x/.config?x=55b0bb710b7fdf44 dashboard link: https://syzkaller.appspot.com/bug?extid=d769eed29cc42d75e2a3 compiler: gcc (GCC) 9.0.0 20181231 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+d769eed29cc42d75e2a3@xxxxxxxxxxxxxxxxxxxxxxxxx BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1530 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 15295, name: syz-executor.1 6 locks held by syz-executor.1/15295: #0: ffff88809740c430 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 #1: ffff888214f62450 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2908 [inline] #1: ffff888214f62450 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x4cf/0x5d0 fs/read_write.c:558 #2: ffff88805241d488 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: inode_lock include/linux/fs.h:797 [inline] #2: ffff88805241d488 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: ext4_buffered_write_iter+0xb3/0x450 fs/ext4/file.c:264 #3: ffff88805241d278 (&ei->i_data_sem){++++}-{3:3}, at: ext4_da_map_blocks fs/ext4/inode.c:1692 [inline] #3: ffff88805241d278 (&ei->i_data_sem){++++}-{3:3}, at: ext4_da_get_block_prep+0xa0d/0x1120 fs/ext4/inode.c:1810 #4: ffff88805241d808 (&ei->i_es_lock){++++}-{2:2}, at: ext4_es_insert_delayed_block+0x12a/0x540 fs/ext4/extents_status.c:1982 #5: ffffc90000da8d60 ((&n->timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:193 [inline] #5: ffffc90000da8d60 ((&n->timer)){+.-.}-{0:0}, at: call_timer_fn+0xdb/0x780 kernel/time/timer.c:1394 Preemption disabled at: [<0000000000000000>] 0x0 CPU: 1 PID: 15295 Comm: syz-executor.1 Not tainted 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 ___might_sleep.cold+0x1f4/0x23d kernel/sched/core.c:6800 down_write+0x6e/0x150 kernel/locking/rwsem.c:1530 crypto_drop_spawn crypto/algapi.c:707 [inline] crypto_drop_spawn+0x4b/0x2b0 crypto/algapi.c:702 shash_free_singlespawn_instance+0x15/0x20 crypto/shash.c:593 crypto_free_instance crypto/algapi.c:68 [inline] crypto_destroy_instance+0x7a/0xc0 crypto/algapi.c:76 crypto_alg_put crypto/internal.h:94 [inline] crypto_alg_put crypto/internal.h:91 [inline] crypto_mod_put crypto/api.c:45 [inline] crypto_destroy_tfm+0x198/0x310 crypto/api.c:566 crypto_free_shash include/crypto/hash.h:722 [inline] sctp_destruct_sock+0x37/0x50 net/sctp/socket.c:5231 __sk_destruct+0x4b/0x7c0 net/core/sock.c:1783 sk_destruct+0xc6/0x100 net/core/sock.c:1827 __sk_free+0xef/0x3d0 net/core/sock.c:1838 sock_wfree+0x129/0x240 net/core/sock.c:2064 skb_release_head_state+0xe2/0x250 net/core/skbuff.c:651 skb_release_all+0x11/0x60 net/core/skbuff.c:662 __kfree_skb net/core/skbuff.c:678 [inline] kfree_skb net/core/skbuff.c:696 [inline] kfree_skb+0xfa/0x410 net/core/skbuff.c:690 neigh_invalidate+0x25c/0x5c0 net/core/neighbour.c:993 neigh_timer_handler+0xdbb/0x1180 net/core/neighbour.c:1080 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x623/0x1600 kernel/time/timer.c:1786 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x192/0x1d0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:546 [inline] smp_apic_timer_interrupt+0x19e/0x600 arch/x86/kernel/apic/apic.c:1140 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 </IRQ> RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline] RIP: 0010:lock_acquire+0x267/0x8f0 kernel/locking/lockdep.c:4937 Code: 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 c6 05 00 00 48 83 3d c5 2d 3b 08 00 0f 84 65 04 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 08 48 c7 RSP: 0018:ffffc90004fa74c8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff132980c RBX: ffff8880868da440 RCX: 5e17927a8ce40e94 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000282 RBP: 0000000000000000 R08: 0000000000000001 R09: fffffbfff1861546 R10: ffffffff8c30aa2f R11: fffffbfff1861545 R12: 0000000000000000 R13: ffff88805241d808 R14: 0000000000000000 R15: 0000000000000000 __raw_write_lock include/linux/rwlock_api_smp.h:210 [inline] _raw_write_lock+0x2a/0x40 kernel/locking/spinlock.c:295 ext4_es_insert_delayed_block+0x12a/0x540 fs/ext4/extents_status.c:1982 ext4_insert_delayed_block fs/ext4/inode.c:1655 [inline] ext4_da_map_blocks fs/ext4/inode.c:1746 [inline] ext4_da_get_block_prep+0x6ea/0x1120 fs/ext4/inode.c:1810 ext4_block_write_begin+0x59a/0x1430 fs/ext4/inode.c:1053 ext4_da_write_begin+0x56e/0xbc0 fs/ext4/inode.c:2995 generic_perform_write+0x20a/0x4e0 mm/filemap.c:3302 ext4_buffered_write_iter+0x1f7/0x450 fs/ext4/file.c:270 ext4_file_write_iter+0x1ec/0x13f0 fs/ext4/file.c:642 call_write_iter include/linux/fs.h:1907 [inline] new_sync_write+0x4a2/0x700 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+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45ca69 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff2b9d83c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050c980 RCX: 000000000045ca69 RDX: 000000006db6e559 RSI: 0000000020000040 RDI: 0000000000000006 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cec R14: 00000000004cf3d4 R15: 00007ff2b9d846d4 ============================= [ BUG: Invalid wait context ] 5.7.0-rc6-syzkaller #0 Tainted: G W ----------------------------- syz-executor.1/15295 is trying to lock: ffffffff89e64330 (crypto_alg_sem){++++}-{3:3}, at: crypto_drop_spawn crypto/algapi.c:707 [inline] ffffffff89e64330 (crypto_alg_sem){++++}-{3:3}, at: crypto_drop_spawn+0x4b/0x2b0 crypto/algapi.c:702 other info that might help us debug this: context-{2:2} 6 locks held by syz-executor.1/15295: #0: ffff88809740c430 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 #1: ffff888214f62450 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2908 [inline] #1: ffff888214f62450 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x4cf/0x5d0 fs/read_write.c:558 #2: ffff88805241d488 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: inode_lock include/linux/fs.h:797 [inline] #2: ffff88805241d488 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: ext4_buffered_write_iter+0xb3/0x450 fs/ext4/file.c:264 #3: ffff88805241d278 (&ei->i_data_sem){++++}-{3:3}, at: ext4_da_map_blocks fs/ext4/inode.c:1692 [inline] #3: ffff88805241d278 (&ei->i_data_sem){++++}-{3:3}, at: ext4_da_get_block_prep+0xa0d/0x1120 fs/ext4/inode.c:1810 #4: ffff88805241d808 (&ei->i_es_lock){++++}-{2:2}, at: ext4_es_insert_delayed_block+0x12a/0x540 fs/ext4/extents_status.c:1982 #5: ffffc90000da8d60 ((&n->timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:193 [inline] #5: ffffc90000da8d60 ((&n->timer)){+.-.}-{0:0}, at: call_timer_fn+0xdb/0x780 kernel/time/timer.c:1394 stack backtrace: CPU: 1 PID: 15295 Comm: syz-executor.1 Tainted: G W 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 print_lock_invalid_wait_context kernel/locking/lockdep.c:4007 [inline] check_wait_context kernel/locking/lockdep.c:4068 [inline] __lock_acquire.cold+0x273/0x3f8 kernel/locking/lockdep.c:4305 lock_acquire+0x1f2/0x8f0 kernel/locking/lockdep.c:4934 down_write+0x8d/0x150 kernel/locking/rwsem.c:1531 crypto_drop_spawn crypto/algapi.c:707 [inline] crypto_drop_spawn+0x4b/0x2b0 crypto/algapi.c:702 shash_free_singlespawn_instance+0x15/0x20 crypto/shash.c:593 crypto_free_instance crypto/algapi.c:68 [inline] crypto_destroy_instance+0x7a/0xc0 crypto/algapi.c:76 crypto_alg_put crypto/internal.h:94 [inline] crypto_alg_put crypto/internal.h:91 [inline] crypto_mod_put crypto/api.c:45 [inline] crypto_destroy_tfm+0x198/0x310 crypto/api.c:566 crypto_free_shash include/crypto/hash.h:722 [inline] sctp_destruct_sock+0x37/0x50 net/sctp/socket.c:5231 __sk_destruct+0x4b/0x7c0 net/core/sock.c:1783 sk_destruct+0xc6/0x100 net/core/sock.c:1827 __sk_free+0xef/0x3d0 net/core/sock.c:1838 sock_wfree+0x129/0x240 net/core/sock.c:2064 skb_release_head_state+0xe2/0x250 net/core/skbuff.c:651 skb_release_all+0x11/0x60 net/core/skbuff.c:662 __kfree_skb net/core/skbuff.c:678 [inline] kfree_skb net/core/skbuff.c:696 [inline] kfree_skb+0xfa/0x410 net/core/skbuff.c:690 neigh_invalidate+0x25c/0x5c0 net/core/neighbour.c:993 neigh_timer_handler+0xdbb/0x1180 net/core/neighbour.c:1080 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x623/0x1600 kernel/time/timer.c:1786 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x192/0x1d0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:546 [inline] smp_apic_timer_interrupt+0x19e/0x600 arch/x86/kernel/apic/apic.c:1140 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 </IRQ> RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline] RIP: 0010:lock_acquire+0x267/0x8f0 kernel/locking/lockdep.c:4937 Code: 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 c6 05 00 00 48 83 3d c5 2d 3b 08 00 0f 84 65 04 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 08 48 c7 RSP: 0018:ffffc90004fa74c8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff132980c RBX: ffff8880868da440 RCX: 5e17927a8ce40e94 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000282 RBP: 0000000000000000 R08: 0000000000000001 R09: fffffbfff1861546 R10: ffffffff8c30aa2f R11: fffffbfff1861545 R12: 0000000000000000 R13: ffff88805241d808 R14: 0000000000000000 R15: 0000000000000000 __raw_write_lock include/linux/rwlock_api_smp.h:210 [inline] _raw_write_lock+0x2a/0x40 kernel/locking/spinlock.c:295 ext4_es_insert_delayed_block+0x12a/0x540 fs/ext4/extents_status.c:1982 ext4_insert_delayed_block fs/ext4/inode.c:1655 [inline] ext4_da_map_blocks fs/ext4/inode.c:1746 [inline] ext4_da_get_block_prep+0x6ea/0x1120 fs/ext4/inode.c:1810 ext4_block_write_begin+0x59a/0x1430 fs/ext4/inode.c:1053 ext4_da_write_begin+0x56e/0xbc0 fs/ext4/inode.c:2995 generic_perform_write+0x20a/0x4e0 mm/filemap.c:3302 ext4_buffered_write_iter+0x1f7/0x450 fs/ext4/file.c:270 ext4_file_write_iter+0x1ec/0x13f0 fs/ext4/file.c:642 call_write_iter include/linux/fs.h:1907 [inline] new_sync_write+0x4a2/0x700 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+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45ca69 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff2b9d83c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050c980 RCX: 000000000045ca69 RDX: 000000006db6e559 RSI: 0000000020000040 RDI: 0000000000000006 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cec R14: 00000000004cf3d4 R15: 00007ff2b9d846d4 --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
