syzbot

loop0: detected capacity change from 0 to 1024
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BUG: KASAN: slab-out-of-bounds in hfsplus_uni2asc+0x680/0x1270 fs/hfsplus/unicode.c:179
Read of size 2 at addr ffff888026806a18 by task syz-executor290/5833

CPU: 1 UID: 0 PID: 5833 Comm: syz-executor290 Not tainted 6.16.0-rc2-syzkaller-00318-g739a6c93cc75 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xd2/0x2b0 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 hfsplus_uni2asc+0x680/0x1270 fs/hfsplus/unicode.c:179
 hfsplus_listxattr+0x58e/0xb80 fs/hfsplus/xattr.c:734
 vfs_listxattr fs/xattr.c:493 [inline]
 listxattr+0x10d/0x2a0 fs/xattr.c:924
 filename_listxattr fs/xattr.c:958 [inline]
 path_listxattrat+0x179/0x3a0 fs/xattr.c:988
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7a0c5e9a99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff61cab798 EFLAGS: 00000246 ORIG_RAX: 00000000000000c3
RAX: ffffffffffffffda RBX: 0031656c69662f2e RCX: 00007f7a0c5e9a99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000
RBP: 00007f7a0c65d5f0 R08: 0000000000000658 R09: 0000555579c4f4c0
R10: 00007fff61cab660 R11: 0000000000000246 R12: 00007fff61cab7c0
R13: 00007fff61cab9e8 R14: 431bde82d7b634db R15: 00007f7a0c63203b
 </TASK>

Allocated by task 5833:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4328 [inline]
 __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4340
 kmalloc_noprof include/linux/slab.h:909 [inline]
 hfsplus_find_init+0x8c/0x1d0 fs/hfsplus/bfind.c:21
 hfsplus_listxattr+0x38f/0xb80 fs/hfsplus/xattr.c:693
 vfs_listxattr fs/xattr.c:493 [inline]
 listxattr+0x10d/0x2a0 fs/xattr.c:924
 filename_listxattr fs/xattr.c:958 [inline]
 path_listxattrat+0x179/0x3a0 fs/xattr.c:988
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888026806800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 0 bytes to the right of
 allocated 536-byte region [ffff888026806800, ffff888026806a18)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26800
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a441dc0 ffffea00018fbc00 dead000000000002
raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a441dc0 ffffea00018fbc00 dead000000000002
head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea00009a0001 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 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 36, tgid 36 (kworker/u8:2), ts 9810587487, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
 alloc_slab_page mm/slub.c:2453 [inline]
 allocate_slab+0x65/0x3b0 mm/slub.c:2619
 new_slab mm/slub.c:2673 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859
 __slab_alloc mm/slub.c:3949 [inline]
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __kmalloc_cache_node_noprof+0x29a/0x3d0 mm/slub.c:4367
 kmalloc_node_noprof include/linux/slab.h:928 [inline]
 blk_mq_alloc_hctx block/blk-mq.c:3997 [inline]
 blk_mq_alloc_and_init_hctx+0x181/0xd60 block/blk-mq.c:4500
 __blk_mq_realloc_hw_ctxs+0x169/0x400 block/blk-mq.c:4531
 blk_mq_realloc_hw_ctxs block/blk-mq.c:4558 [inline]
 blk_mq_init_allocated_queue+0x400/0x1490 block/blk-mq.c:4590
 blk_mq_alloc_queue+0x197/0x290 block/blk-mq.c:4400
 scsi_alloc_sdev+0x76d/0xb50 drivers/scsi/scsi_scan.c:339
 scsi_probe_and_add_lun+0x1cb/0x4520 drivers/scsi/scsi_scan.c:1210
 __scsi_scan_target+0x1dd/0xd10 drivers/scsi/scsi_scan.c:1775
 scsi_scan_channel drivers/scsi/scsi_scan.c:1863 [inline]
 scsi_scan_host_selected+0x372/0x690 drivers/scsi/scsi_scan.c:1892
 do_scsi_scan_host drivers/scsi/scsi_scan.c:2031 [inline]
 do_scan_async+0x124/0x760 drivers/scsi/scsi_scan.c:2041
 async_run_entry_fn+0xa8/0x3f0 kernel/async.c:129
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888026806900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888026806980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888026806a00: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc
                            ^
 ffff888026806a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888026806b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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