loop4: detected capacity change from 0 to 1024 ================================================================== BUG: KASAN: slab-out-of-bounds in hfsplus_uni2asc+0x5b9/0x1240 fs/hfsplus/unicode.c:186 Read of size 2 at addr ffff88801cdd5218 by task syz.4.111/4970 CPU: 0 PID: 4970 Comm: syz.4.111 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 hfsplus_uni2asc+0x5b9/0x1240 fs/hfsplus/unicode.c:186 hfsplus_listxattr+0x58b/0xb80 fs/hfsplus/xattr.c:740 vfs_listxattr fs/xattr.c:448 [inline] listxattr+0x283/0x2e0 fs/xattr.c:783 path_listxattr+0xd9/0x1b0 fs/xattr.c:807 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f19d8942be9 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:00007f19d6baa038 EFLAGS: 00000246 ORIG_RAX: 00000000000000c3 RAX: ffffffffffffffda RBX: 00007f19d8b79fa0 RCX: 00007f19d8942be9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000040 RBP: 00007f19d89c5e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f19d8b7a038 R14: 00007f19d8b79fa0 R15: 00007fff85af0ba8 Allocated by task 4970: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:609 [inline] hfsplus_find_init+0x85/0x1c0 fs/hfsplus/bfind.c:21 hfsplus_listxattr+0x38c/0xb80 fs/hfsplus/xattr.c:700 vfs_listxattr fs/xattr.c:448 [inline] listxattr+0x283/0x2e0 fs/xattr.c:783 path_listxattr+0xd9/0x1b0 fs/xattr.c:807 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88801cdd5000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 536 bytes inside of 1024-byte region [ffff88801cdd5000, ffff88801cdd5400) The buggy address belongs to the page: page:ffffea0000737400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1cdd0 head:ffffea0000737400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888016841dc0 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4226, ts 66735354843, free_ts 66619888852 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1975 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] __kmalloc_node_track_caller+0x1fc/0x3a0 mm/slub.c:4958 kmalloc_reserve net/core/skbuff.c:356 [inline] __alloc_skb+0x22c/0x750 net/core/skbuff.c:427 alloc_skb include/linux/skbuff.h:1162 [inline] ndisc_alloc_skb+0xa6/0x420 net/ipv6/ndisc.c:422 ndisc_send_ns+0x29e/0x840 net/ipv6/ndisc.c:631 addrconf_dad_work+0xa47/0x1520 net/ipv6/addrconf.c:4198 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x94/0x280 mm/page_alloc.c:3396 free_slab mm/slub.c:2015 [inline] discard_slab mm/slub.c:2021 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2507 put_cpu_partial+0x12d/0x190 mm/slub.c:2587 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] kmem_cache_alloc_node+0x12d/0x2d0 mm/slub.c:3256 __alloc_skb+0xf4/0x750 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] alloc_skb_with_frags+0xa7/0x730 net/core/skbuff.c:6170 sock_alloc_send_pskb+0x853/0x980 net/core/sock.c:2531 unix_dgram_sendmsg+0x5ef/0x1890 net/unix/af_unix.c:1809 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x423/0x580 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2071 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff88801cdd5100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801cdd5180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88801cdd5200: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88801cdd5280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801cdd5300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================