syzbot

======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc1-syzkaller #0 Not tainted
------------------------------------------------------
syz-fuzzer/8471 is trying to acquire lock:
ffffffff8ba9c3a0 (fs_reclaim){+.+.}-{0:0}, at: fs_reclaim_acquire+0xf7/0x160 mm/page_alloc.c:4574

but task is already holding lock:
ffff8880b9c4d660 (lock#2){-.-.}-{2:2}, at: __alloc_pages_bulk+0x4ad/0x1870 mm/page_alloc.c:5279

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (lock#2){-.-.}-{2:2}:
       local_lock_acquire include/linux/local_lock_internal.h:42 [inline]
       rmqueue_pcplist mm/page_alloc.c:3663 [inline]
       rmqueue mm/page_alloc.c:3701 [inline]
       get_page_from_freelist+0x4aa/0x2f80 mm/page_alloc.c:4163
       __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5374
       alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244
       alloc_slab_page mm/slub.c:1713 [inline]
       allocate_slab+0x32b/0x4c0 mm/slub.c:1853
       new_slab mm/slub.c:1916 [inline]
       new_slab_objects mm/slub.c:2662 [inline]
       ___slab_alloc+0x4ba/0x820 mm/slub.c:2825
       __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2865
       slab_alloc_node mm/slub.c:2947 [inline]
       slab_alloc mm/slub.c:2989 [inline]
       kmem_cache_alloc+0x372/0x3a0 mm/slub.c:2994
       anon_vma_chain_alloc mm/rmap.c:136 [inline]
       anon_vma_clone+0xe0/0x5f0 mm/rmap.c:282
       anon_vma_fork+0x82/0x630 mm/rmap.c:345
       dup_mmap kernel/fork.c:554 [inline]
       dup_mm+0x9a0/0x1380 kernel/fork.c:1379
       copy_mm kernel/fork.c:1431 [inline]
       copy_process+0x71ec/0x74d0 kernel/fork.c:2119
       kernel_clone+0xe7/0xac0 kernel/fork.c:2509
       __do_sys_clone+0xc8/0x110 kernel/fork.c:2626
       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

-> #2 (&anon_vma->rwsem){++++}-{3:3}:
       down_write+0x92/0x150 kernel/locking/rwsem.c:1406
       anon_vma_lock_write include/linux/rmap.h:116 [inline]
       __vma_adjust+0x30e/0x2680 mm/mmap.c:868
       vma_adjust include/linux/mm.h:2546 [inline]
       __split_vma+0x2b3/0x550 mm/mmap.c:2770
       split_vma+0x95/0xd0 mm/mmap.c:2799
       mprotect_fixup+0x71c/0x940 mm/mprotect.c:483
       do_mprotect_pkey+0x558/0x9a0 mm/mprotect.c:636
       __do_sys_mprotect mm/mprotect.c:662 [inline]
       __se_sys_mprotect mm/mprotect.c:659 [inline]
       __x64_sys_mprotect+0x74/0xb0 mm/mprotect.c:659
       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

-> #1 (&mapping->i_mmap_rwsem){++++}-{3:3}:
       down_write+0x92/0x150 kernel/locking/rwsem.c:1406
       i_mmap_lock_write include/linux/fs.h:494 [inline]
       dma_resv_lockdep+0x341/0x536 drivers/dma-buf/dma-resv.c:689
       do_one_initcall+0x103/0x650 init/main.c:1282
       do_initcall_level init/main.c:1355 [inline]
       do_initcalls init/main.c:1371 [inline]
       do_basic_setup init/main.c:1391 [inline]
       kernel_init_freeable+0x6b8/0x741 init/main.c:1593
       kernel_init+0x1a/0x1d0 init/main.c:1485
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

-> #0 (fs_reclaim){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3051 [inline]
       check_prevs_add kernel/locking/lockdep.c:3174 [inline]
       validate_chain kernel/locking/lockdep.c:3789 [inline]
       __lock_acquire+0x2a07/0x54a0 kernel/locking/lockdep.c:5015
       lock_acquire kernel/locking/lockdep.c:5625 [inline]
       lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
       __fs_reclaim_acquire mm/page_alloc.c:4552 [inline]
       fs_reclaim_acquire+0x117/0x160 mm/page_alloc.c:4566
       prepare_alloc_pages+0x15c/0x580 mm/page_alloc.c:5164
       __alloc_pages+0x12f/0x500 mm/page_alloc.c:5363
       alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244
       stack_depot_save+0x39d/0x4e0 lib/stackdepot.c:303
       save_stack+0x15e/0x1e0 mm/page_owner.c:120
       __set_page_owner+0x50/0x290 mm/page_owner.c:181
       prep_new_page mm/page_alloc.c:2433 [inline]
       __alloc_pages_bulk+0x8b9/0x1870 mm/page_alloc.c:5301
       alloc_pages_bulk_array_node include/linux/gfp.h:557 [inline]
       vm_area_alloc_pages mm/vmalloc.c:2793 [inline]
       __vmalloc_area_node mm/vmalloc.c:2863 [inline]
       __vmalloc_node_range+0x39d/0x960 mm/vmalloc.c:2966
       __vmalloc_node mm/vmalloc.c:3015 [inline]
       vzalloc+0x67/0x80 mm/vmalloc.c:3085
       n_tty_open+0x16/0x170 drivers/tty/n_tty.c:1848
       tty_ldisc_open+0x9b/0x110 drivers/tty/tty_ldisc.c:449
       tty_ldisc_setup+0x43/0x100 drivers/tty/tty_ldisc.c:766
       tty_init_dev.part.0+0x1f4/0x610 drivers/tty/tty_io.c:1453
       tty_init_dev+0x5b/0x80 drivers/tty/tty_io.c:1419
       ptmx_open drivers/tty/pty.c:834 [inline]
       ptmx_open+0x112/0x360 drivers/tty/pty.c:800
       chrdev_open+0x266/0x770 fs/char_dev.c:414
       do_dentry_open+0x4c8/0x11d0 fs/open.c:826
       do_open fs/namei.c:3374 [inline]
       path_openat+0x1c23/0x27f0 fs/namei.c:3507
       do_filp_open+0x1aa/0x400 fs/namei.c:3534
       do_sys_openat2+0x16d/0x420 fs/open.c:1204
       do_sys_open fs/open.c:1220 [inline]
       __do_sys_openat fs/open.c:1236 [inline]
       __se_sys_openat fs/open.c:1231 [inline]
       __x64_sys_openat+0x13f/0x1f0 fs/open.c:1231
       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

other info that might help us debug this:

Chain exists of:
  fs_reclaim --> &anon_vma->rwsem --> lock#2

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(lock#2);
                               lock(&anon_vma->rwsem);
                               lock(lock#2);
  lock(fs_reclaim);

 *** DEADLOCK ***

4 locks held by syz-fuzzer/8471:
 #0: ffffffff8c378148 (tty_mutex){+.+.}-{3:3}, at: ptmx_open drivers/tty/pty.c:833 [inline]
 #0: ffffffff8c378148 (tty_mutex){+.+.}-{3:3}, at: ptmx_open+0x103/0x360 drivers/tty/pty.c:800
 #1: ffff88802ef5b1c0 (&tty->legacy_mutex){+.+.}-{3:3}, at: tty_lock+0xbd/0x120 drivers/tty/tty_mutex.c:20
 #2: ffff88802ef5b098 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:300 [inline]
 #2: ffff88802ef5b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock+0x61/0xb0 drivers/tty/tty_ldisc.c:324
 #3: ffff8880b9c4d660 (lock#2){-.-.}-{2:2}, at: __alloc_pages_bulk+0x4ad/0x1870 mm/page_alloc.c:5279

stack backtrace:
CPU: 0 PID: 8471 Comm: syz-fuzzer Not tainted 5.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105
 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2131
 check_prev_add kernel/locking/lockdep.c:3051 [inline]
 check_prevs_add kernel/locking/lockdep.c:3174 [inline]
 validate_chain kernel/locking/lockdep.c:3789 [inline]
 __lock_acquire+0x2a07/0x54a0 kernel/locking/lockdep.c:5015
 lock_acquire kernel/locking/lockdep.c:5625 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
 __fs_reclaim_acquire mm/page_alloc.c:4552 [inline]
 fs_reclaim_acquire+0x117/0x160 mm/page_alloc.c:4566
 prepare_alloc_pages+0x15c/0x580 mm/page_alloc.c:5164
 __alloc_pages+0x12f/0x500 mm/page_alloc.c:5363
 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244
 stack_depot_save+0x39d/0x4e0 lib/stackdepot.c:303
 save_stack+0x15e/0x1e0 mm/page_owner.c:120
 __set_page_owner+0x50/0x290 mm/page_owner.c:181
 prep_new_page mm/page_alloc.c:2433 [inline]
 __alloc_pages_bulk+0x8b9/0x1870 mm/page_alloc.c:5301
 alloc_pages_bulk_array_node include/linux/gfp.h:557 [inline]
 vm_area_alloc_pages mm/vmalloc.c:2793 [inline]
 __vmalloc_area_node mm/vmalloc.c:2863 [inline]
 __vmalloc_node_range+0x39d/0x960 mm/vmalloc.c:2966
 __vmalloc_node mm/vmalloc.c:3015 [inline]
 vzalloc+0x67/0x80 mm/vmalloc.c:3085
 n_tty_open+0x16/0x170 drivers/tty/n_tty.c:1848
 tty_ldisc_open+0x9b/0x110 drivers/tty/tty_ldisc.c:449
 tty_ldisc_setup+0x43/0x100 drivers/tty/tty_ldisc.c:766
 tty_init_dev.part.0+0x1f4/0x610 drivers/tty/tty_io.c:1453
 tty_init_dev+0x5b/0x80 drivers/tty/tty_io.c:1419
 ptmx_open drivers/tty/pty.c:834 [inline]
 ptmx_open+0x112/0x360 drivers/tty/pty.c:800
 chrdev_open+0x266/0x770 fs/char_dev.c:414
 do_dentry_open+0x4c8/0x11d0 fs/open.c:826
 do_open fs/namei.c:3374 [inline]
 path_openat+0x1c23/0x27f0 fs/namei.c:3507
 do_filp_open+0x1aa/0x400 fs/namei.c:3534
 do_sys_openat2+0x16d/0x420 fs/open.c:1204
 do_sys_open fs/open.c:1220 [inline]
 __do_sys_openat fs/open.c:1236 [inline]
 __se_sys_openat fs/open.c:1231 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1231
 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: 0033:0x4af20a
Code: e8 3b 82 fb ff 48 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 4c 8b 54 24 28 4c 8b 44 24 30 4c 8b 4c 24 38 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 40 ff ff ff ff 48 c7 44 24 48
RSP: 002b:000000c00030b3f8 EFLAGS: 00000216 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000000c00001c000 RCX: 00000000004af20a
RDX: 0000000000000000 RSI: 000000c0001778c0 RDI: ffffffffffffff9c
RBP: 000000c00030b470 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 000000000000018d
R13: 000000000000018c R14: 0000000000000200 R15: 000000c0004ad0e0
BUG: sleeping function called from invalid context at mm/page_alloc.c:5167
in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 8471, name: syz-fuzzer
INFO: lockdep is turned off.
irq event stamp: 147860
hardirqs last  enabled at (147859): [<ffffffff892c3e30>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
hardirqs last  enabled at (147859): [<ffffffff892c3e30>] _raw_spin_unlock_irqrestore+0x50/0x70 kernel/locking/spinlock.c:191
hardirqs last disabled at (147860): [<ffffffff81b27147>] __alloc_pages_bulk+0x1017/0x1870 mm/page_alloc.c:5279
softirqs last  enabled at (140836): [<ffffffff814628be>] invoke_softirq kernel/softirq.c:432 [inline]
softirqs last  enabled at (140836): [<ffffffff814628be>] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636
softirqs last disabled at (140781): [<ffffffff814628be>] invoke_softirq kernel/softirq.c:432 [inline]
softirqs last disabled at (140781): [<ffffffff814628be>] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636
CPU: 0 PID: 8471 Comm: syz-fuzzer Not tainted 5.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105
 ___might_sleep.cold+0x1f1/0x237 kernel/sched/core.c:9154
 prepare_alloc_pages+0x3da/0x580 mm/page_alloc.c:5167
 __alloc_pages+0x12f/0x500 mm/page_alloc.c:5363
 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244
 stack_depot_save+0x39d/0x4e0 lib/stackdepot.c:303
 save_stack+0x15e/0x1e0 mm/page_owner.c:120
 __set_page_owner+0x50/0x290 mm/page_owner.c:181
 prep_new_page mm/page_alloc.c:2433 [inline]
 __alloc_pages_bulk+0x8b9/0x1870 mm/page_alloc.c:5301
 alloc_pages_bulk_array_node include/linux/gfp.h:557 [inline]
 vm_area_alloc_pages mm/vmalloc.c:2793 [inline]
 __vmalloc_area_node mm/vmalloc.c:2863 [inline]
 __vmalloc_node_range+0x39d/0x960 mm/vmalloc.c:2966
 __vmalloc_node mm/vmalloc.c:3015 [inline]
 vzalloc+0x67/0x80 mm/vmalloc.c:3085
 n_tty_open+0x16/0x170 drivers/tty/n_tty.c:1848
 tty_ldisc_open+0x9b/0x110 drivers/tty/tty_ldisc.c:449
 tty_ldisc_setup+0x43/0x100 drivers/tty/tty_ldisc.c:766
 tty_init_dev.part.0+0x1f4/0x610 drivers/tty/tty_io.c:1453
 tty_init_dev+0x5b/0x80 drivers/tty/tty_io.c:1419
 ptmx_open drivers/tty/pty.c:834 [inline]
 ptmx_open+0x112/0x360 drivers/tty/pty.c:800
 chrdev_open+0x266/0x770 fs/char_dev.c:414
 do_dentry_open+0x4c8/0x11d0 fs/open.c:826
 do_open fs/namei.c:3374 [inline]
 path_openat+0x1c23/0x27f0 fs/namei.c:3507
 do_filp_open+0x1aa/0x400 fs/namei.c:3534
 do_sys_openat2+0x16d/0x420 fs/open.c:1204
 do_sys_open fs/open.c:1220 [inline]
 __do_sys_openat fs/open.c:1236 [inline]
 __se_sys_openat fs/open.c:1231 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1231
 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: 0033:0x4af20a
Code: e8 3b 82 fb ff 48 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 4c 8b 54 24 28 4c 8b 44 24 30 4c 8b 4c 24 38 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 40 ff ff ff ff 48 c7 44 24 48
RSP: 002b:000000c00030b3f8 EFLAGS: 00000216 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000000c00001c000 RCX: 00000000004af20a
RDX: 0000000000000000 RSI: 000000c0001778c0 RDI: ffffffffffffff9c
RBP: 000000c00030b470 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 000000000000018d
R13: 000000000000018c R14: 0000000000000200 R15: 000000c0004ad0e0
can: request_module (can-proto-0) failed.
can: request_module (can-proto-0) failed.
can: request_module (can-proto-0) failed.
base_sock_release(ffff888039290fc0) sk=ffff888037ef0000