================================================================== BUG: KASAN: slab-out-of-bounds in afs_split_string fs/afs/addr_prefs.c:51 [inline] BUG: KASAN: slab-out-of-bounds in afs_proc_addr_prefs_write+0x123b/0x14e0 fs/afs/addr_prefs.c:415 Read of size 1 at addr ffff88805e899f90 by task syz.3.10155/30287 CPU: 1 UID: 0 PID: 30287 Comm: syz.3.10155 Not tainted 6.13.0-rc2-syzkaller-00333-ga0e3919a2df2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xc3/0x620 mm/kasan/report.c:489 kasan_report+0xd9/0x110 mm/kasan/report.c:602 afs_split_string fs/afs/addr_prefs.c:51 [inline] afs_proc_addr_prefs_write+0x123b/0x14e0 fs/afs/addr_prefs.c:415 proc_simple_write+0x114/0x1b0 fs/proc/generic.c:815 pde_write fs/proc/inode.c:330 [inline] proc_reg_write+0x23d/0x330 fs/proc/inode.c:342 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f67ce585d19 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:00007f67cf38a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f67ce775fa0 RCX: 00007f67ce585d19 RDX: 000000000000000f RSI: 0000000020000340 RDI: 0000000000000003 RBP: 00007f67ce601a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f67ce775fa0 R15: 00007ffdce0c36f8 Allocated by task 30287: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4298 [inline] __kmalloc_node_track_caller_noprof+0x21d/0x520 mm/slub.c:4317 memdup_user_nul+0x2b/0x110 mm/util.c:305 proc_simple_write+0xc7/0x1b0 fs/proc/generic.c:812 pde_write fs/proc/inode.c:330 [inline] proc_reg_write+0x23d/0x330 fs/proc/inode.c:342 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805e899f80 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 0 bytes to the right of allocated 16-byte region [ffff88805e899f80, ffff88805e899f90) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5e899 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801ac41640 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080800080 00000001f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 22475, tgid 22475 (syz-executor), ts 724732385748, free_ts 724728941519 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474 __alloc_pages_noprof+0x223/0x25b0 mm/page_alloc.c:4751 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_slab_page mm/slub.c:2425 [inline] allocate_slab mm/slub.c:2589 [inline] new_slab+0xca/0x410 mm/slub.c:2642 ___slab_alloc+0xce2/0x1650 mm/slub.c:3830 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __do_kmalloc_node mm/slub.c:4297 [inline] __kmalloc_node_noprof+0x2f0/0x520 mm/slub.c:4304 __kvmalloc_node_noprof+0xad/0x1a0 mm/util.c:650 xt_jumpstack_alloc net/netfilter/x_tables.c:1355 [inline] xt_replace_table+0x1e3/0x940 net/netfilter/x_tables.c:1394 __do_replace+0x1d3/0x9e0 net/ipv4/netfilter/arp_tables.c:912 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline] do_ip6t_set_ctl+0x990/0xc20 net/ipv6/netfilter/ip6_tables.c:1644 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x135/0x170 net/ipv6/ipv6_sockglue.c:998 tcp_setsockopt+0xa4/0x100 net/ipv4/tcp.c:4030 do_sock_setsockopt+0x222/0x480 net/socket.c:2313 __sys_setsockopt+0x1a0/0x230 net/socket.c:2338 page last free pid 27365 tgid 27365 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0x661/0x1080 mm/page_alloc.c:2657 tlb_batch_list_free mm/mmu_gather.c:159 [inline] tlb_finish_mmu+0x237/0x7b0 mm/mmu_gather.c:468 exit_mmap+0x3df/0xb20 mm/mmap.c:1681 __mmput+0x12a/0x4c0 kernel/fork.c:1353 mmput+0x62/0x70 kernel/fork.c:1375 exit_mm kernel/exit.c:570 [inline] do_exit+0x9bf/0x2d70 kernel/exit.c:925 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 __do_sys_exit_group kernel/exit.c:1098 [inline] __se_sys_exit_group kernel/exit.c:1096 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1096 x64_sys_call+0x151f/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88805e899e80: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc ffff88805e899f00: 00 01 fc fc fa fb fc fc fa fb fc fc fa fb fc fc >ffff88805e899f80: 00 00 fc fc fa fb fc fc fa fb fc fc fa fb fc fc ^ ffff88805e89a000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805e89a080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================