RBP: 00007f2a4e3c41d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffc3703037f R14: 00007f2a4e3c4300 R15: 0000000000022000
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 8697 Comm: syz-executor.4 Not tainted 6.3.0-rc7-next-20230418 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:folio_wait_stable+0x23/0xe0
Code: 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 fd 53 e8 32 58 e7 ff 48 8d 7d 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a4 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b
RSP: 0018:ffff88804348f9f0 EFLAGS: 00010213
RAX: dffffc0000000000 RBX: ffff88801bf5d1f0 RCX: ffffc90002e22000
RDX: 0000000000000001 RSI: ffffffff81647cce RDI: 000000000000000c
RBP: fffffffffffffff4 R08: 0000000000000001 R09: ffffffff856c1693
R10: fffffbfff0ad82d2 R11: 0000000000000001 R12: 0000000000000000
R13: ffff88801bf5d418 R14: 0000000000000000 R15: 000000000000a000
FS: 00007f2a4e3c4700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000b000 CR3: 000000003b44c000 CR4: 0000000000350ef0
Call Trace:
ext4_da_write_begin+0x38d/0x830
generic_perform_write+0x25a/0x580
ext4_buffered_write_iter+0x164/0x460
ext4_file_write_iter+0x3ff/0x1950
vfs_write+0x9bb/0xdd0
ksys_write+0x12b/0x260
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f2a50e4eb19
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2a4e3c4188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f2a50f61f60 RCX: 00007f2a50e4eb19
RDX: 0000000000041030 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00007f2a4e3c41d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffc3703037f R14: 00007f2a4e3c4300 R15: 0000000000022000
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:folio_wait_stable+0x23/0xe0
Code: 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 fd 53 e8 32 58 e7 ff 48 8d 7d 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a4 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b
RSP: 0018:ffff88804348f9f0 EFLAGS: 00010213
RAX: dffffc0000000000 RBX: ffff88801bf5d1f0 RCX: ffffc90002e22000
RDX: 0000000000000001 RSI: ffffffff81647cce RDI: 000000000000000c
RBP: fffffffffffffff4 R08: 0000000000000001 R09: ffffffff856c1693
R10: fffffbfff0ad82d2 R11: 0000000000000001 R12: 0000000000000000
R13: ffff88801bf5d418 R14: 0000000000000000 R15: 000000000000a000
FS: 00007f2a4e3c4700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000b000 CR3: 000000003b44c000 CR4: 0000000000350ef0
==================================================================
BUG: KASAN: slab-use-after-free in rwsem_down_write_slowpath+0x13a6/0x14a0
Read of size 4 at addr ffff88801d29d074 by task syz-executor.4/270
CPU: 1 PID: 270 Comm: syz-executor.4 Tainted: G D 6.3.0-rc7-next-20230418 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
dump_stack_lvl+0x91/0xf0
print_report+0xcc/0x620
kasan_report+0xc0/0xf0
rwsem_down_write_slowpath+0x13a6/0x14a0
down_write+0x1c3/0x1f0
vfs_unlink+0xd9/0x930
do_unlinkat+0x3b9/0x650
__x64_sys_unlink+0xca/0x110
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f2a50e4e457
Code: 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc3702f4c8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2a50e4e457
RDX: 00007ffc3702f500 RSI: 00007ffc3702f500 RDI: 00007ffc3702f590
RBP: 00007ffc3702f590 R08: 0000000000000001 R09: 00007ffc3702f360
R10: 0000555556596d13 R11: 0000000000000206 R12: 00007f2a50ea8105
R13: 00007ffc37030650 R14: 0000555556596c20 R15: 00007ffc37030690
Allocated by task 8696:
kasan_save_stack+0x22/0x50
kasan_set_track+0x25/0x30
__kasan_slab_alloc+0x59/0x70
kmem_cache_alloc_node+0x189/0x3a0
copy_process+0x3c2/0x7330
kernel_clone+0xeb/0x7d0
__do_sys_clone+0xba/0x100
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
Freed by task 238:
kasan_save_stack+0x22/0x50
kasan_set_track+0x25/0x30
kasan_save_free_info+0x2e/0x50
__kasan_slab_free+0x10a/0x190
kmem_cache_free+0xff/0x4a0
delayed_put_task_struct+0x1c9/0x240
rcu_core+0x899/0x2750
__do_softirq+0x1b7/0x7d4
Last potentially related work creation:
kasan_save_stack+0x22/0x50
__kasan_record_aux_stack+0x95/0xb0
__call_rcu_common.constprop.0+0x6a/0xb90
put_task_struct_rcu_user+0x87/0xd0
__schedule+0x995/0x2a00
schedule+0xdb/0x1a0
exit_to_user_mode_prepare+0x95/0x180
irqentry_exit_to_user_mode+0x9/0x30
asm_sysvec_apic_timer_interrupt+0x1a/0x20
Second to last potentially related work creation:
kasan_save_stack+0x22/0x50
__kasan_record_aux_stack+0x95/0xb0
__call_rcu_common.constprop.0+0x6a/0xb90
put_task_struct_rcu_user+0x87/0xd0
wait_consider_task+0x2f59/0x3c40
do_wait+0x777/0xbc0
kernel_wait4+0x150/0x260
__do_sys_wait4+0x143/0x150
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
The buggy address belongs to the object at ffff88801d29d040
which belongs to the cache task_struct of size 6592
The buggy address is located 52 bytes inside of
freed 6592-byte region [ffff88801d29d040, ffff88801d29ea00)
The buggy address belongs to the physical page:
page:0000000068094e98 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d298
head:0000000068094e98 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88800fc69541
anon flags: 0x100000000010200(slab|head|node=0|zone=1)
page_type: 0xffffffff()
raw: 0100000000010200 ffff888008797640 ffffea00003f1200 dead000000000003
raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88800fc69541
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88801d29cf00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
ffff88801d29cf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88801d29d000: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
^
ffff88801d29d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88801d29d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 90 nop
1: 90 nop
2: 90 nop
3: 90 nop
4: 90 nop
5: 90 nop
6: 90 nop
7: f3 0f 1e fa endbr64
b: 55 push %rbp
c: 48 89 fd mov %rdi,%rbp
f: 53 push %rbx
10: e8 32 58 e7 ff callq 0xffe75847
15: 48 8d 7d 18 lea 0x18(%rbp),%rdi
19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
20: fc ff df
23: 48 89 fa mov %rdi,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2e: 0f 85 a4 00 00 00 jne 0xd8
34: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
3b: fc ff df
3e: 48 rex.W
3f: 8b .byte 0x8b