RBP: 00007f40a8ef81d0 R08: 0000000000000000 R09: 0000000000000000 R10: 000000010000027f R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffc3fe7c60f R14: 00007f40a8ef8300 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: 8150 Comm: syz-executor.0 Not tainted 6.3.0-rc6-next-20230413 #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 62 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:ffff888043c77488 EFLAGS: 00010213 RAX: dffffc0000000000 RBX: ffff88801bf32068 RCX: ffffc900007cf000 RDX: 0000000000000001 RSI: ffffffff81646e3e RDI: 000000000000000c RBP: fffffffffffffff4 R08: 0000000000000001 R09: ffffffff856c1213 R10: fffffbfff0ad8242 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88801bf32290 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f40a8ef8700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5aac102ba0 CR3: 000000000a4b0000 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 do_iter_readv_writev+0x211/0x3c0 do_iter_write+0x189/0x7e0 vfs_iter_write+0x74/0xb0 iter_file_splice_write+0x73f/0xcb0 direct_splice_actor+0x113/0x180 splice_direct_to_actor+0x33a/0x8c0 do_splice_direct+0x1bc/0x290 do_sendfile+0xb1d/0x12b0 __x64_sys_sendfile64+0x1d5/0x210 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f40ab982b19 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:00007f40a8ef8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f40aba95f60 RCX: 00007f40ab982b19 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004 RBP: 00007f40a8ef81d0 R08: 0000000000000000 R09: 0000000000000000 R10: 000000010000027f R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffc3fe7c60f R14: 00007f40a8ef8300 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 62 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:ffff888043c77488 EFLAGS: 00010213 RAX: dffffc0000000000 RBX: ffff88801bf32068 RCX: ffffc900007cf000 RDX: 0000000000000001 RSI: ffffffff81646e3e RDI: 000000000000000c RBP: fffffffffffffff4 R08: 0000000000000001 R09: ffffffff856c1213 R10: fffffbfff0ad8242 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88801bf32290 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f40a8ef8700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5aac102ba0 CR3: 000000000a4b0000 CR4: 0000000000350ef0 netlink: 12 bytes leftover after parsing attributes in process `syz-executor.6'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.6'. ================================================================== BUG: KASAN: slab-use-after-free in rwsem_down_write_slowpath+0x13a6/0x14a0 Read of size 4 at addr ffff88801a530034 by task syz-executor.0/266 CPU: 0 PID: 266 Comm: syz-executor.0 Tainted: G D 6.3.0-rc6-next-20230413 #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: 0033:0x7f40ab982457 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:00007ffc3fe7b758 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f40ab982457 RDX: 00007ffc3fe7b790 RSI: 00007ffc3fe7b790 RDI: 00007ffc3fe7b820 RBP: 00007ffc3fe7b820 R08: 0000000000000001 R09: 00007ffc3fe7b5f0 R10: 0000555556943d13 R11: 0000000000000206 R12: 00007f40ab9dc105 R13: 00007ffc3fe7c8e0 R14: 0000555556943c20 R15: 00007ffc3fe7c920 Allocated by task 8149: 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 8149: 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 _free_event+0xab4/0x1150 perf_event_release_kernel+0x5b8/0x7a0 perf_release+0x37/0x50 __fput+0x263/0xa40 task_work_run+0x174/0x280 exit_to_user_mode_prepare+0x17d/0x180 syscall_exit_to_user_mode+0x1d/0x50 do_syscall_64+0x4c/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc 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_reschedule_ipi+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 __schedule+0x995/0x2a00 __cond_resched+0x46/0x70 kmem_cache_alloc+0x32c/0x390 security_file_alloc+0x38/0x170 __alloc_file+0xb6/0x240 alloc_empty_file+0x71/0x190 path_openat+0xd8/0x2750 do_filp_open+0x1ba/0x410 do_sys_openat2+0x171/0x4c0 __x64_sys_openat+0x143/0x200 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc The buggy address belongs to the object at ffff88801a530000 which belongs to the cache task_struct of size 6592 The buggy address is located 52 bytes inside of freed 6592-byte region [ffff88801a530000, ffff88801a5319c0) The buggy address belongs to the physical page: page:000000004278ec48 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1a530 head:000000004278ec48 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff8880084c1f81 anon flags: 0x100000000010200(slab|head|node=0|zone=1) page_type: 0xffffffff() raw: 0100000000010200 ffff888008792640 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff8880084c1f81 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88801a52ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801a52ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801a530000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801a530080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801a530100: 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 62 58 e7 ff callq 0xffe75877 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