capability: warning: `syz.4.8' uses deprecated v2 capabilities in a way that may be insecure ====================================================== WARNING: possible circular locking dependency detected 6.1.112-syzkaller #0 Not tainted ------------------------------------------------------ syz.4.8/3738 is trying to acquire lock: ffff888055050ae0 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xc8/0x720 fs/gfs2/quota.c:682 but task is already holding lock: ffff8880687385e8 (&ip->i_rw_mutex){++++}-{3:3}, at: __gfs2_iomap_alloc+0x2b7/0x2090 fs/gfs2/bmap.c:679 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&ip->i_rw_mutex){++++}-{3:3}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 down_read+0xad/0xa30 kernel/locking/rwsem.c:1520 __gfs2_iomap_get+0x178/0x1480 fs/gfs2/bmap.c:856 gfs2_iomap_get+0xdb/0x150 fs/gfs2/bmap.c:1396 bh_get+0x286/0x800 fs/gfs2/quota.c:385 qdsb_get+0x209/0x3b0 fs/gfs2/quota.c:522 gfs2_quota_hold+0x19d/0x5c0 fs/gfs2/quota.c:608 gfs2_quota_lock+0x9f/0x450 fs/gfs2/quota.c:1076 gfs2_quota_lock_check fs/gfs2/quota.h:50 [inline] alloc_dinode+0x1c9/0x580 fs/gfs2/inode.c:393 gfs2_create_inode+0x1019/0x1c00 fs/gfs2/inode.c:711 gfs2_atomic_open+0xe1/0x220 fs/gfs2/inode.c:1292 atomic_open fs/namei.c:3347 [inline] lookup_open fs/namei.c:3455 [inline] open_last_lookups fs/namei.c:3552 [inline] path_openat+0xf4e/0x2e60 fs/namei.c:3782 do_filp_open+0x230/0x480 fs/namei.c:3812 do_sys_openat2+0x13b/0x4f0 fs/open.c:1318 do_sys_open fs/open.c:1334 [inline] __do_sys_openat fs/open.c:1350 [inline] __se_sys_openat fs/open.c:1345 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1345 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&sdp->sd_quota_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747 do_qc+0xc8/0x720 fs/gfs2/quota.c:682 gfs2_quota_change+0x2db/0x8c0 fs/gfs2/quota.c:1295 gfs2_alloc_blocks+0x1e50/0x28c0 fs/gfs2/rgrp.c:2494 __gfs2_iomap_alloc+0x4f0/0x2090 fs/gfs2/bmap.c:705 gfs2_iomap_alloc+0x155/0x1f0 fs/gfs2/bmap.c:1409 gfs2_allocate_page_backing+0x12e/0x250 fs/gfs2/file.c:394 gfs2_page_mkwrite+0x1135/0x1460 fs/gfs2/file.c:524 do_page_mkwrite+0x1a1/0x5f0 mm/memory.c:3009 do_shared_fault mm/memory.c:4694 [inline] do_fault mm/memory.c:4762 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x22eb/0x5340 mm/memory.c:5292 fixup_user_fault+0x295/0x4b0 mm/gup.c:1365 fault_in_safe_writeable+0x138/0x250 mm/gup.c:1861 fault_in_iov_iter_writeable+0xdb/0x270 lib/iov_iter.c:399 gfs2_file_read_iter+0x92a/0xcd0 fs/gfs2/file.c:992 call_read_iter include/linux/fs.h:2259 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x88d/0xbf0 fs/read_write.c:470 ksys_read+0x19c/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ip->i_rw_mutex); lock(&sdp->sd_quota_mutex); lock(&ip->i_rw_mutex); lock(&sdp->sd_quota_mutex); *** DEADLOCK *** 6 locks held by syz.4.8/3738: #0: ffff888075a47268 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ba/0x360 fs/file.c:1058 #1: ffff8880243d26d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline] #1: ffff8880243d26d8 (&mm->mmap_lock){++++}-{3:3}, at: fixup_user_fault+0x2fb/0x4b0 mm/gup.c:1387 #2: ffff888055048558 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x1a1/0x5f0 mm/memory.c:3009 #3: ffff888055048650 (sb_internal#4){.+.+}-{0:0}, at: gfs2_trans_begin+0x6d/0xe0 fs/gfs2/trans.c:118 #4: ffff888055051058 (&sdp->sd_log_flush_lock){.+.+}-{3:3}, at: __gfs2_trans_begin+0x558/0x940 fs/gfs2/trans.c:87 #5: ffff8880687385e8 (&ip->i_rw_mutex){++++}-{3:3}, at: __gfs2_iomap_alloc+0x2b7/0x2090 fs/gfs2/bmap.c:679 stack backtrace: CPU: 0 PID: 3738 Comm: syz.4.8 Not tainted 6.1.112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747 do_qc+0xc8/0x720 fs/gfs2/quota.c:682 gfs2_quota_change+0x2db/0x8c0 fs/gfs2/quota.c:1295 gfs2_alloc_blocks+0x1e50/0x28c0 fs/gfs2/rgrp.c:2494 __gfs2_iomap_alloc+0x4f0/0x2090 fs/gfs2/bmap.c:705 gfs2_iomap_alloc+0x155/0x1f0 fs/gfs2/bmap.c:1409 gfs2_allocate_page_backing+0x12e/0x250 fs/gfs2/file.c:394 gfs2_page_mkwrite+0x1135/0x1460 fs/gfs2/file.c:524 do_page_mkwrite+0x1a1/0x5f0 mm/memory.c:3009 do_shared_fault mm/memory.c:4694 [inline] do_fault mm/memory.c:4762 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x22eb/0x5340 mm/memory.c:5292 fixup_user_fault+0x295/0x4b0 mm/gup.c:1365 fault_in_safe_writeable+0x138/0x250 mm/gup.c:1861 fault_in_iov_iter_writeable+0xdb/0x270 lib/iov_iter.c:399 gfs2_file_read_iter+0x92a/0xcd0 fs/gfs2/file.c:992 call_read_iter include/linux/fs.h:2259 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x88d/0xbf0 fs/read_write.c:470 ksys_read+0x19c/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f31c397dff9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f31c4845038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f31c3b35f80 RCX: 00007f31c397dff9 RDX: 0000000000002020 RSI: 0000000020006380 RDI: 0000000000000004 RBP: 00007f31c39f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f31c3b35f80 R15: 00007ffd3d3fea68