syzbot

syz-executor774[4168]: segfault at 0 ip 0000000000000000 sp 00000000200000c8 error 14
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
======================================================
WARNING: possible circular locking dependency detected
5.15.171-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor774/4168 is trying to acquire lock:
ffff888070a98660 (&oi->ip_alloc_sem){+.+.}-{3:3}, at: ocfs2_try_remove_refcount_tree+0xb2/0x330 fs/ocfs2/refcounttree.c:932

but task is already holding lock:
ffff888070a986f8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_try_remove_refcount_tree+0xa1/0x330 fs/ocfs2/refcounttree.c:931

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&oi->ip_xattr_sem){++++}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498
       ocfs2_init_acl+0x398/0x930 fs/ocfs2/acl.c:365
       ocfs2_mknod+0x1e8f/0x2cd0 fs/ocfs2/namei.c:408
       ocfs2_create+0x194/0x430 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3462 [inline]
       open_last_lookups fs/namei.c:3532 [inline]
       path_openat+0x130a/0x2f20 fs/namei.c:3739
       do_filp_open+0x21c/0x460 fs/namei.c:3769
       file_open_name fs/open.c:1198 [inline]
       filp_open+0x25d/0x2c0 fs/open.c:1218
       do_coredump+0x2549/0x31e0 fs/coredump.c:767
       get_signal+0xc06/0x14e0 kernel/signal.c:2886
       arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
       handle_signal_work kernel/entry/common.c:154 [inline]
       exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
       irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
       exc_page_fault+0x342/0x700 arch/x86/mm/fault.c:1504
       asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606

-> #3 (jbd2_handle){.+.+}-{0:0}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       start_this_handle+0x12e1/0x1570 fs/jbd2/transaction.c:464
       jbd2__journal_start+0x2d1/0x5c0 fs/jbd2/transaction.c:521
       jbd2_journal_start+0x25/0x30 fs/jbd2/transaction.c:560
       ocfs2_start_trans+0x3c2/0x6f0 fs/ocfs2/journal.c:354
       ocfs2_mknod+0x15bb/0x2cd0 fs/ocfs2/namei.c:359
       ocfs2_create+0x194/0x430 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3462 [inline]
       open_last_lookups fs/namei.c:3532 [inline]
       path_openat+0x130a/0x2f20 fs/namei.c:3739
       do_filp_open+0x21c/0x460 fs/namei.c:3769
       file_open_name fs/open.c:1198 [inline]
       filp_open+0x25d/0x2c0 fs/open.c:1218
       do_coredump+0x2549/0x31e0 fs/coredump.c:767
       get_signal+0xc06/0x14e0 kernel/signal.c:2886
       arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
       handle_signal_work kernel/entry/common.c:154 [inline]
       exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
       irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
       exc_page_fault+0x342/0x700 arch/x86/mm/fault.c:1504
       asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606

-> #2 (&journal->j_trans_barrier){.+.+}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498
       ocfs2_start_trans+0x3b7/0x6f0 fs/ocfs2/journal.c:352
       ocfs2_mknod+0x15bb/0x2cd0 fs/ocfs2/namei.c:359
       ocfs2_create+0x194/0x430 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3462 [inline]
       open_last_lookups fs/namei.c:3532 [inline]
       path_openat+0x130a/0x2f20 fs/namei.c:3739
       do_filp_open+0x21c/0x460 fs/namei.c:3769
       file_open_name fs/open.c:1198 [inline]
       filp_open+0x25d/0x2c0 fs/open.c:1218
       do_coredump+0x2549/0x31e0 fs/coredump.c:767
       get_signal+0xc06/0x14e0 kernel/signal.c:2886
       arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
       handle_signal_work kernel/entry/common.c:154 [inline]
       exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
       irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
       exc_page_fault+0x342/0x700 arch/x86/mm/fault.c:1504
       asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606

-> #1 (sb_internal#2){.+.+}-{0:0}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1813 [inline]
       sb_start_intwrite include/linux/fs.h:1930 [inline]
       ocfs2_start_trans+0x2b2/0x6f0 fs/ocfs2/journal.c:350
       ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
       ocfs2_truncate_file+0x661/0x14f0 fs/ocfs2/file.c:496
       ocfs2_setattr+0x165e/0x1c70 fs/ocfs2/file.c:1212
       notify_change+0xc6d/0xf50 fs/attr.c:505
       do_truncate+0x21c/0x300 fs/open.c:65
       do_coredump+0x2d8e/0x31e0 fs/coredump.c:803
       get_signal+0xc06/0x14e0 kernel/signal.c:2886
       arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
       handle_signal_work kernel/entry/common.c:154 [inline]
       exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
       irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
       exc_page_fault+0x342/0x700 arch/x86/mm/fault.c:1504
       asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606

-> #0 (&oi->ip_alloc_sem){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       ocfs2_try_remove_refcount_tree+0xb2/0x330 fs/ocfs2/refcounttree.c:932
       ocfs2_truncate_file+0xe3c/0x14f0 fs/ocfs2/file.c:517
       ocfs2_setattr+0x165e/0x1c70 fs/ocfs2/file.c:1212
       notify_change+0xc6d/0xf50 fs/attr.c:505
       do_truncate+0x21c/0x300 fs/open.c:65
       do_coredump+0x2d8e/0x31e0 fs/coredump.c:803
       get_signal+0xc06/0x14e0 kernel/signal.c:2886
       arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
       handle_signal_work kernel/entry/common.c:154 [inline]
       exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
       irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
       exc_page_fault+0x342/0x700 arch/x86/mm/fault.c:1504
       asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606

other info that might help us debug this:

Chain exists of:
  &oi->ip_alloc_sem --> jbd2_handle --> &oi->ip_xattr_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_xattr_sem);
                               lock(jbd2_handle);
                               lock(&oi->ip_xattr_sem);
  lock(&oi->ip_alloc_sem);

 *** DEADLOCK ***

2 locks held by syz-executor774/4168:
 #0: ffff888070a989c8 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
 #0: ffff888070a989c8 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: do_truncate+0x208/0x300 fs/open.c:63
 #1: ffff888070a986f8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_try_remove_refcount_tree+0xa1/0x330 fs/ocfs2/refcounttree.c:931

stack backtrace:
CPU: 0 PID: 4168 Comm: syz-executor774 Not tainted 5.15.171-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 down_write+0x38/0x60 kernel/locking/rwsem.c:1551
 ocfs2_try_remove_refcount_tree+0xb2/0x330 fs/ocfs2/refcounttree.c:932
 ocfs2_truncate_file+0xe3c/0x14f0 fs/ocfs2/file.c:517
 ocfs2_setattr+0x165e/0x1c70 fs/ocfs2/file.c:1212
 notify_change+0xc6d/0xf50 fs/attr.c:505
 do_truncate+0x21c/0x300 fs/open.c:65
 do_coredump+0x2d8e/0x31e0 fs/coredump.c:803
 get_signal+0xc06/0x14e0 kernel/signal.c:2886
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
 exc_page_fault+0x342/0x700 arch/x86/mm/fault.c:1504
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 002b:00000000200000c8 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fbbfb39b089
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000004000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000555500000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000f4240
R13: 00007fbbfb3ed99c R14: 00007fbbfb3e40e2 R15: 00007ffd1b83a220
 </TASK>
syz-executor774 (4168) used greatest stack depth: 17296 bytes left