================================================================== BUG: KASAN: slab-out-of-bounds in iov_iter_revert+0x1da/0x5f0 lib/iov_iter.c:633 Read of size 4 at addr ffff88807e51fe18 by task kworker/u8:9/17757 CPU: 0 UID: 0 PID: 17757 Comm: kworker/u8:9 Not tainted 6.15.0-syzkaller-09113-g8477ab143069 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound netfs_write_collection_worker Call Trace: 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 iov_iter_revert+0x1da/0x5f0 lib/iov_iter.c:633 netfs_retry_write_stream fs/netfs/write_retry.c:44 [inline] netfs_retry_writes+0x1645/0x1840 fs/netfs/write_retry.c:231 netfs_collect_write_results fs/netfs/write_collect.c:352 [inline] netfs_write_collection_worker+0x2007/0x2bd0 fs/netfs/write_collect.c:374 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 20665: 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] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:905 [inline] add_stack_record_to_list mm/page_owner.c:172 [inline] inc_stack_record_count mm/page_owner.c:214 [inline] __set_page_owner+0x25c/0x4a0 mm/page_owner.c:333 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1710 prep_new_page mm/page_alloc.c:1718 [inline] get_page_from_freelist+0x21d1/0x22b0 mm/page_alloc.c:3680 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 __alloc_pages_noprof+0xa/0x30 mm/page_alloc.c:5004 __alloc_pages_node_noprof include/linux/gfp.h:284 [inline] alloc_pages_node_noprof include/linux/gfp.h:311 [inline] ___kmalloc_large_node+0x85/0x210 mm/slub.c:4271 __kmalloc_large_node_noprof+0x18/0x90 mm/slub.c:4299 __do_kmalloc_node mm/slub.c:4315 [inline] __kmalloc_node_track_caller_noprof+0x361/0x4e0 mm/slub.c:4346 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1336 [inline] alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6668 sock_alloc_send_pskb+0x857/0x990 net/core/sock.c:2999 packet_alloc_skb net/packet/af_packet.c:2981 [inline] packet_snd net/packet/af_packet.c:3074 [inline] packet_sendmsg+0x3672/0x53f0 net/packet/af_packet.c:3163 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:727 __sys_sendto+0x3bd/0x520 net/socket.c:2180 __do_sys_sendto net/socket.c:2187 [inline] __se_sys_sendto net/socket.c:2183 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2183 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 ffff88807e51fe00 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 8 bytes to the right of allocated 16-byte region [ffff88807e51fe00, ffff88807e51fe10) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807e51fce0 pfn:0x7e51f flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801a441640 ffffea00009f6a80 dead000000000002 raw: ffff88807e51fce0 000000000080007e 00000000f5000000 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 5820, tgid 5820 (syz-executor), ts 1077738933482, free_ts 1077738816912 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1710 prep_new_page mm/page_alloc.c:1718 [inline] get_page_from_freelist+0x21d1/0x22b0 mm/page_alloc.c:3680 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_slab_page mm/slub.c:2452 [inline] allocate_slab+0x65/0x3b0 mm/slub.c:2618 new_slab mm/slub.c:2672 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858 __slab_alloc mm/slub.c:3948 [inline] __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kvmalloc_node_noprof+0x430/0x600 mm/slub.c:5012 xt_jumpstack_alloc net/netfilter/x_tables.c:1355 [inline] xt_replace_table+0x180/0x790 net/netfilter/x_tables.c:1394 __do_replace+0x15a/0x980 net/ipv6/netfilter/ip6_tables.c:1081 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline] do_ip6t_set_ctl+0xa16/0xce0 net/ipv6/netfilter/ip6_tables.c:1644 nf_setsockopt+0x26c/0x290 net/netfilter/nf_sockopt.c:101 do_sock_setsockopt+0x257/0x3e0 net/socket.c:2296 __sys_setsockopt net/socket.c:2321 [inline] __do_sys_setsockopt net/socket.c:2327 [inline] __se_sys_setsockopt net/socket.c:2324 [inline] __x64_sys_setsockopt+0x18b/0x220 net/socket.c:2324 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 page last free pid 5820 tgid 5820 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1254 [inline] __free_frozen_pages+0xc65/0xe50 mm/page_alloc.c:2717 ___free_pages_bulk mm/kasan/shadow.c:332 [inline] __kasan_populate_vmalloc mm/kasan/shadow.c:375 [inline] kasan_populate_vmalloc+0x118/0x1a0 mm/kasan/shadow.c:417 alloc_vmap_area+0x1e2b/0x24c0 mm/vmalloc.c:2067 __get_vm_area_node+0x1f8/0x300 mm/vmalloc.c:3170 __vmalloc_node_range_noprof+0x301/0x1340 mm/vmalloc.c:3837 __vmalloc_node_noprof mm/vmalloc.c:3940 [inline] vzalloc_noprof+0xb2/0xf0 mm/vmalloc.c:4014 __do_replace+0xab/0x980 net/ipv6/netfilter/ip6_tables.c:1063 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline] do_ip6t_set_ctl+0xa16/0xce0 net/ipv6/netfilter/ip6_tables.c:1644 nf_setsockopt+0x26c/0x290 net/netfilter/nf_sockopt.c:101 do_sock_setsockopt+0x257/0x3e0 net/socket.c:2296 __sys_setsockopt net/socket.c:2321 [inline] __do_sys_setsockopt net/socket.c:2327 [inline] __se_sys_setsockopt net/socket.c:2324 [inline] __x64_sys_setsockopt+0x18b/0x220 net/socket.c:2324 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 Memory state around the buggy address: ffff88807e51fd00: 00 04 fc fc 00 00 fc fc fa fb fc fc 00 00 fc fc ffff88807e51fd80: fa fb fc fc 00 00 fc fc fa fb fc fc 00 00 fc fc >ffff88807e51fe00: 00 00 fc fc 00 00 fc fc 00 07 fc fc 00 00 fc fc ^ ffff88807e51fe80: fa fb fc fc fa fb fc fc 00 00 fc fc 00 00 fc fc ffff88807e51ff00: 00 00 fc fc fa fb fc fc 00 00 fc fc 00 00 fc fc ==================================================================