bcachefs (loop4): reading snapshots table
bcachefs (loop4): reading snapshots done
bcachefs (loop4): done starting filesystem
==================================================================
BUG: KASAN: slab-out-of-bounds in bch2_dirent_init_name+0x396/0x8b0
Write of size 1985 at addr ffff88810f4bc22d by task syz.4.97/6861

CPU: 1 UID: 0 PID: 6861 Comm: syz.4.97 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 kasan_check_range+0x2b0/0x2c0
 __asan_memset+0x22/0x50
 bch2_dirent_init_name+0x396/0x8b0
 bch2_dirent_create_key+0x2a1/0x5f0
 bch2_dirent_create+0xc5/0xc80
 bch2_link_trans+0x39e/0x560
 __bch2_link+0x231/0x3f0
 bch2_symlink+0x183/0x240
 vfs_symlink+0x143/0x2f0
 do_symlinkat+0x1b1/0x3f0
 __x64_sys_symlink+0x7a/0x90
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbbb018ec29
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbbb0f4b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007fbbb03d6090 RCX: 00007fbbb018ec29
RDX: 0000000000000000 RSI: 0000200000000800 RDI: 0000200000000540
RBP: 00007fbbb0211e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbbb03d6128 R14: 00007fbbb03d6090 R15: 00007ffedbef6098
 </TASK>

Allocated by task 6861:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_noprof+0x411/0x7f0
 __bch2_trans_kmalloc+0x396/0x9d0
 bch2_dirent_create_key+0x113/0x5f0
 bch2_dirent_create+0xc5/0xc80
 bch2_link_trans+0x39e/0x560
 __bch2_link+0x231/0x3f0
 bch2_symlink+0x183/0x240
 vfs_symlink+0x143/0x2f0
 do_symlinkat+0x1b1/0x3f0
 __x64_sys_symlink+0x7a/0x90
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88810f4bc000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 557 bytes inside of
 allocated 2048-byte region [ffff88810f4bc000, ffff88810f4bc800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10f4b8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff88801ac42000 ffffea00041be000 dead000000000002
raw: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff88801ac42000 ffffea00041be000 dead000000000002
head: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000
head: 057ff00000000003 ffffea00043d2e01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5842, tgid 5842 (syz-executor), ts 56595223005, free_ts 56566824206
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x2365/0x2440
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x96/0x3a0
 ___slab_alloc+0xe94/0x1920
 __slab_alloc+0x65/0x100
 __kmalloc_noprof+0x471/0x7f0
 sk_prot_alloc+0xe7/0x220
 sk_alloc+0x3a/0x370
 __netlink_create+0x65/0x260
 __netlink_kernel_create+0x131/0x710
 xfrm_user_net_init+0xa7/0x160
 ops_init+0x35c/0x5c0
 setup_net+0xfe/0x320
 copy_net_ns+0x34e/0x4e0
page last free pid 5846 tgid 5846 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __slab_free+0x2e7/0x390
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 __kmalloc_noprof+0x3c3/0x7f0
 tomoyo_supervisor+0xbd5/0x1480
 tomoyo_path_permission+0x25a/0x380
 tomoyo_check_open_permission+0x2b6/0x3b0
 security_file_open+0xb1/0x270
 do_dentry_open+0x384/0x13f0
 vfs_open+0x3b/0x340
 path_openat+0x2ee5/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170

Memory state around the buggy address:
 ffff88810f4bc700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88810f4bc780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88810f4bc800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88810f4bc880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88810f4bc900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
