=============================
WARNING: suspicious RCU usage
6.3.0-rc2-syzkaller-00006-gfc89d7fb499b #0 Not tainted
-----------------------------
lib/maple_tree.c:856 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
6 locks held by syz-executor.0/21643:
#0: ffff888028bf8fe8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe7/0x100 fs/file.c:1047
#1: ffff88802bbec460 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:637
#2: ffff88807ddd3888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x285/0x600 fs/kernfs/file.c:325
#3: ffff8880177dd490 (kn->active#72){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2a9/0x600 fs/kernfs/file.c:326
#4: ffffffff8c90b388 (ksm_thread_mutex){+.+.}-{3:3}, at: run_store+0xd5/0xa30 mm/ksm.c:2953
#5: ffff88802ba4d4d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
#5: ffff88802ba4d4d8 (&mm->mmap_lock){++++}-{3:3}, at: unmerge_and_remove_all_rmap_items mm/ksm.c:990 [inline]
#5: ffff88802ba4d4d8 (&mm->mmap_lock){++++}-{3:3}, at: run_store+0x2a9/0xa30 mm/ksm.c:2959
stack backtrace:
CPU: 1 PID: 21643 Comm: syz-executor.0 Not tainted 6.3.0-rc2-syzkaller-00006-gfc89d7fb499b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x136/0x150 lib/dump_stack.c:106
lockdep_rcu_suspicious+0x208/0x3a0 kernel/locking/lockdep.c:6599
mas_root lib/maple_tree.c:856 [inline]
mas_start lib/maple_tree.c:1357 [inline]
mas_state_walk lib/maple_tree.c:3838 [inline]
mas_walk+0x473/0x6e0 lib/maple_tree.c:5052
mas_find+0x150/0x200 lib/maple_tree.c:6030
vma_next include/linux/mm.h:745 [inline]
unmerge_and_remove_all_rmap_items mm/ksm.c:991 [inline]
run_store+0x2e7/0xa30 mm/ksm.c:2959
kobj_attr_store+0x54/0x80 lib/kobject.c:832
sysfs_kf_write+0x114/0x170 fs/sysfs/file.c:136
kernfs_fop_write_iter+0x3f1/0x600 fs/kernfs/file.c:334
call_write_iter include/linux/fs.h:1851 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9ed/0xe10 fs/read_write.c:584
ksys_write+0x12b/0x250 fs/read_write.c:637
do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
__do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
entry_SYSENTER_compat_after_hwframe+0x70/0x82
RIP: 0023:0xf7fdc579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f7fb65cc EFLAGS: 00000296 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
0: 10 06 adc %al,(%rsi)
2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi
6: 10 07 adc %al,(%rdi)
8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi
c: 10 08 adc %cl,(%rax)
e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi
1e: 00 51 52 add %dl,0x52(%rcx)
21: 55 push %rbp
22: 89 e5 mov %esp,%ebp
24: 0f 34 sysenter
26: cd 80 int $0x80
* 28: 5d pop %rbp <-- trapping instruction
29: 5a pop %rdx
2a: 59 pop %rcx
2b: c3 retq
2c: 90 nop
2d: 90 nop
2e: 90 nop
2f: 90 nop
30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi
37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi