syzbot has found a reproducer for the following issue on: HEAD commit: b831f83e40a2 Merge tag 'bpf-6.11-rc7' of git://git.kernel... git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=13ceca8b980000 kernel config: https://syzkaller.appspot.com/x/.config?x=8926d683f62db53e dashboard link: https://syzkaller.appspot.com/bug?extid=950a0cdaa2fdd14f5bdc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11849200580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12472ffb980000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/7de57e317906/disk-b831f83e.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/83081a33fb63/vmlinux-b831f83e.xz kernel image: https://storage.googleapis.com/syzbot-assets/1a98ffa98a52/bzImage-b831f83e.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/9f8e1f401e6c/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+950a0cdaa2fdd14f5bdc@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task syz-executor292:5263 blocked for more than 143 seconds. Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor292 state:D stack:27952 pid:5263 tgid:5250 ppid:5245 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580 inode_lock include/linux/fs.h:800 [inline] open_last_lookups fs/namei.c:3644 [inline] path_openat+0x7fb/0x3470 fs/namei.c:3883 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_open fs/open.c:1439 [inline] __se_sys_open fs/open.c:1435 [inline] __x64_sys_open+0x225/0x270 fs/open.c:1435 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4a1e867bc9 RSP: 002b:00007f4a1e7fc218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f4a1e8f96b8 RCX: 00007f4a1e867bc9 RDX: 0000000000000000 RSI: 000000000010b942 RDI: 0000000020000080 RBP: 00007f4a1e8f96b0 R08: 00007ffee00fdc47 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4a1e8f96bc R13: 00007f4a1e8bc0c0 R14: 0031656c69662f2e R15: 0030656c69662f2e </TASK> INFO: task syz-executor292:5264 blocked for more than 144 seconds. Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor292 state:D stack:27952 pid:5264 tgid:5251 ppid:5246 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580 inode_lock include/linux/fs.h:800 [inline] open_last_lookups fs/namei.c:3644 [inline] path_openat+0x7fb/0x3470 fs/namei.c:3883 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_open fs/open.c:1439 [inline] __se_sys_open fs/open.c:1435 [inline] __x64_sys_open+0x225/0x270 fs/open.c:1435 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4a1e867bc9 RSP: 002b:00007f4a1e7fc218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f4a1e8f96b8 RCX: 00007f4a1e867bc9 RDX: 0000000000000000 RSI: 000000000010b942 RDI: 0000000020000080 RBP: 00007f4a1e8f96b0 R08: 00007ffee00fdc47 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4a1e8f96bc R13: 00007f4a1e8bc0c0 R14: 0031656c69662f2e R15: 0030656c69662f2e </TASK> INFO: task syz-executor292:5265 blocked for more than 145 seconds. Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor292 state:D stack:27952 pid:5265 tgid:5253 ppid:5248 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580 inode_lock include/linux/fs.h:800 [inline] open_last_lookups fs/namei.c:3644 [inline] path_openat+0x7fb/0x3470 fs/namei.c:3883 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_open fs/open.c:1439 [inline] __se_sys_open fs/open.c:1435 [inline] __x64_sys_open+0x225/0x270 fs/open.c:1435 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4a1e867bc9 RSP: 002b:00007f4a1e7fc218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f4a1e8f96b8 RCX: 00007f4a1e867bc9 RDX: 0000000000000000 RSI: 000000000010b942 RDI: 0000000020000080 RBP: 00007f4a1e8f96b0 R08: 00007ffee00fdc47 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4a1e8f96bc R13: 00007f4a1e8bc0c0 R14: 0031656c69662f2e R15: 0030656c69662f2e </TASK> INFO: task syz-executor292:5266 blocked for more than 146 seconds. Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor292 state:D stack:27928 pid:5266 tgid:5254 ppid:5247 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580 inode_lock include/linux/fs.h:800 [inline] open_last_lookups fs/namei.c:3644 [inline] path_openat+0x7fb/0x3470 fs/namei.c:3883 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_open fs/open.c:1439 [inline] __se_sys_open fs/open.c:1435 [inline] __x64_sys_open+0x225/0x270 fs/open.c:1435 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4a1e867bc9 RSP: 002b:00007f4a1e7fc218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f4a1e8f96b8 RCX: 00007f4a1e867bc9 RDX: 0000000000000000 RSI: 000000000010b942 RDI: 0000000020000080 RBP: 00007f4a1e8f96b0 R08: 00007ffee00fdc47 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4a1e8f96bc R13: 00007f4a1e8bc0c0 R14: 0031656c69662f2e R15: 0030656c69662f2e </TASK> INFO: task syz-executor292:5262 blocked for more than 147 seconds. Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor292 state:D stack:27320 pid:5262 tgid:5255 ppid:5249 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580 inode_lock include/linux/fs.h:800 [inline] open_last_lookups fs/namei.c:3644 [inline] path_openat+0x7fb/0x3470 fs/namei.c:3883 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_open fs/open.c:1439 [inline] __se_sys_open fs/open.c:1435 [inline] __x64_sys_open+0x225/0x270 fs/open.c:1435 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4a1e867bc9 RSP: 002b:00007f4a1e7fc218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f4a1e8f96b8 RCX: 00007f4a1e867bc9 RDX: 0000000000000000 RSI: 000000000010b942 RDI: 0000000020000080 RBP: 00007f4a1e8f96b0 R08: 00007ffee00fdc47 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4a1e8f96bc R13: 00007f4a1e8bc0c0 R14: 0031656c69662f2e R15: 0030656c69662f2e </TASK> Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 1 lock held by kswapd0/89: 2 locks held by getty/4976: #0: ffff88803030c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000312b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz-executor292/5257: 1 lock held by syz-executor292/5263: #0: ffff8880783006c0 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: inode_lock include/linux/fs.h:800 [inline] #0: ffff8880783006c0 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: open_last_lookups fs/namei.c:3644 [inline] #0: ffff8880783006c0 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: path_openat+0x7fb/0x3470 fs/namei.c:3883 1 lock held by syz-executor292/5256: 1 lock held by syz-executor292/5264: #0: ffff888078300180 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: inode_lock include/linux/fs.h:800 [inline] #0: ffff888078300180 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: open_last_lookups fs/namei.c:3644 [inline] #0: ffff888078300180 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: path_openat+0x7fb/0x3470 fs/namei.c:3883 1 lock held by syz-executor292/5258: 1 lock held by syz-executor292/5265: #0: ffff8880783c06c0 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: inode_lock include/linux/fs.h:800 [inline] #0: ffff8880783c06c0 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: open_last_lookups fs/namei.c:3644 [inline] #0: ffff8880783c06c0 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: path_openat+0x7fb/0x3470 fs/namei.c:3883 1 lock held by syz-executor292/5259: 1 lock held by syz-executor292/5266: #0: ffff888078300c00 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: inode_lock include/linux/fs.h:800 [inline] #0: ffff888078300c00 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: open_last_lookups fs/namei.c:3644 [inline] #0: ffff888078300c00 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: path_openat+0x7fb/0x3470 fs/namei.c:3883 2 locks held by syz-executor292/5260: 1 lock held by syz-executor292/5262: #0: ffff8880783c0180 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: inode_lock include/linux/fs.h:800 [inline] #0: ffff8880783c0180 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: open_last_lookups fs/namei.c:3644 [inline] #0: ffff8880783c0180 (&type->i_mutex_dir_key#6){++++}-{3:3}, at: path_openat+0x7fb/0x3470 fs/namei.c:3883 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5259 Comm: syz-executor292 Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:209 Code: 89 fb e8 23 00 00 00 48 8b 3d bc 26 75 0c 48 89 de 5b e9 53 75 58 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 c0 d6 03 00 65 8b 15 50 4a RSP: 0018:ffffc90003796ee0 EFLAGS: 00000246 RAX: ffffffff90106f08 RBX: ffffffff90106f0c RCX: ffff88807f0ebc00 RDX: 0000000000000000 RSI: ffffffff82086c46 RDI: ffffffff82086c88 RBP: ffffffff82086c88 R08: ffffffff81412c60 R09: ffffc900037970b0 R10: 0000000000000003 R11: ffffffff817f2f30 R12: ffffffff90106f08 R13: ffffffff90106f08 R14: ffffffff82086c46 R15: ffffffff90106f08 FS: 00007f4a1e81d6c0(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000559ac1abfe30 CR3: 00000000287e6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> __orc_find arch/x86/kernel/unwind_orc.c:99 [inline] orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x531/0x2a00 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3992 [inline] slab_alloc_node mm/slub.c:4041 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4048 alloc_buffer_head+0x2a/0x290 fs/buffer.c:3025 folio_alloc_buffers+0x241/0x5b0 fs/buffer.c:929 create_empty_buffers+0x3a/0x740 fs/buffer.c:1671 block_read_full_folio+0x25c/0xcd0 fs/buffer.c:2387 filemap_read_folio+0x1a0/0x790 mm/filemap.c:2355 do_read_cache_folio+0x134/0x820 mm/filemap.c:3789 do_read_cache_page+0x30/0x200 mm/filemap.c:3855 read_mapping_page include/linux/pagemap.h:907 [inline] dir_get_page fs/sysv/dir.c:64 [inline] sysv_find_entry+0x1af/0x410 fs/sysv/dir.c:157 sysv_inode_by_name+0x98/0x1f0 fs/sysv/dir.c:374 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38 lookup_open fs/namei.c:3556 [inline] open_last_lookups fs/namei.c:3647 [inline] path_openat+0x11cc/0x3470 fs/namei.c:3883 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4a1e867bc9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 18 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4a1e81d218 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f4a1e8f96a8 RCX: 00007f4a1e867bc9 RDX: 0000000000000800 RSI: 0000000020000240 RDI: 00000000ffffff9c RBP: 00007f4a1e8f96a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000039 R11: 0000000000000246 R12: 00007f4a1e8f96ac R13: 00007f4a1e8bc0c0 R14: 0031656c69662f2e R15: 0030656c69662f2e </TASK> INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.204 msecs --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing.
