================================================================== BUG: KASAN: slab-use-after-free in rose_get_neigh+0x1b6/0x6f0 net/rose/rose_route.c:692 Read of size 1 at addr ffff88807e446830 by task syz.2.145/6380 CPU: 1 UID: 0 PID: 6380 Comm: syz.2.145 Not tainted 6.14.0-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 rose_get_neigh+0x1b6/0x6f0 net/rose/rose_route.c:692 rose_connect+0x465/0x1190 net/rose/af_rose.c:816 __sys_connect_file net/socket.c:2038 [inline] __sys_connect+0x28c/0x2d0 net/socket.c:2057 __do_sys_connect net/socket.c:2063 [inline] __se_sys_connect net/socket.c:2060 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2060 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x82/0x160 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fdde018d169 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:00007fdde0fc9038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007fdde03a5fa0 RCX: 00007fdde018d169 RDX: 0000000000000040 RSI: 0000200000000040 RDI: 0000000000000007 RBP: 00007fdde020e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdde03a5fa0 R15: 00007ffe093df7d8 Allocated by task 6096: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x82/0x90 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x256/0x370 mm/slub.c:4362 kmalloc_noprof include/linux/slab.h:905 [inline] rose_add_node+0x209/0xdb0 net/rose/rose_route.c:85 rose_rt_ioctl+0xac2/0xf80 net/rose/rose_route.c:747 rose_ioctl+0x3ca/0x9e0 net/rose/af_rose.c:1380 sock_do_ioctl+0x114/0x470 net/socket.c:1190 sock_ioctl+0x644/0x900 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x82/0x160 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 6373: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x36/0x50 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2389 [inline] slab_free mm/slub.c:4646 [inline] kfree+0x181/0x440 mm/slub.c:4845 rose_rt_device_down+0x6e5/0x740 net/rose/rose_route.c:522 rose_device_event+0x5f2/0x690 net/rose/af_rose.c:248 notifier_call_chain+0x1a5/0x3e0 kernel/notifier.c:85 __dev_notify_flags+0x209/0x410 net/core/dev.c:-1 netif_change_flags+0xf0/0x1a0 net/core/dev.c:9441 dev_change_flags+0x146/0x270 net/core/dev_api.c:68 dev_ioctl+0x80f/0x1260 net/core/dev_ioctl.c:821 sock_do_ioctl+0x2a1/0x470 net/socket.c:1204 sock_ioctl+0x644/0x900 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x82/0x160 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff88807e446800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 48 bytes inside of freed 512-byte region [ffff88807e446800, ffff88807e446a00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e444 head: order:2 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 ffff88801a441c80 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a441c80 dead000000000122 0000000000000000 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001f91101 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6024, tgid 6024 (syz-executor), ts 143371123317, free_ts 143288092337 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ec/0x220 mm/page_alloc.c:1717 prep_new_page mm/page_alloc.c:1725 [inline] get_page_from_freelist+0x34d7/0x3660 mm/page_alloc.c:3652 __alloc_frozen_pages_noprof+0x211/0x5a0 mm/page_alloc.c:4934 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2459 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2623 new_slab mm/slub.c:2676 [inline] ___slab_alloc+0xc55/0x1510 mm/slub.c:3862 __slab_alloc+0x58/0xa0 mm/slub.c:3952 __slab_alloc_node mm/slub.c:4027 [inline] slab_alloc_node mm/slub.c:4188 [inline] __do_kmalloc_node mm/slub.c:4330 [inline] __kmalloc_noprof+0x2e5/0x490 mm/slub.c:4343 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] fib6_info_alloc+0x2e/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x445/0x1280 net/ipv6/route.c:3801 addrconf_f6i_alloc+0x3c7/0x7f0 net/ipv6/route.c:4630 ipv6_add_addr+0x5d4/0x10d0 net/ipv6/addrconf.c:1121 inet6_addr_add+0x41d/0xfa0 net/ipv6/addrconf.c:3049 inet6_rtm_newaddr+0xc19/0x11b0 net/ipv6/addrconf.c:5059 rtnetlink_rcv_msg+0x80f/0xd70 net/core/rtnetlink.c:6955 netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2534 page last free pid 6035 tgid 6035 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xdd0/0x1070 mm/page_alloc.c:2680 __slab_free+0x2c6/0x390 mm/slub.c:4557 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x60 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4151 [inline] slab_alloc_node mm/slub.c:4200 [inline] kmem_cache_alloc_noprof+0x1dc/0x350 mm/slub.c:4207 ext4_mb_new_blocks+0x667/0x4de0 fs/ext4/mballoc.c:6197 ext4_ext_map_blocks+0x1c09/0x7d50 fs/ext4/extents.c:4379 ext4_map_create_blocks fs/ext4/inode.c:519 [inline] ext4_map_blocks+0x909/0x1a70 fs/ext4/inode.c:705 ext4_getblk+0x1fc/0x890 fs/ext4/inode.c:852 ext4_bread+0x2e/0x180 fs/ext4/inode.c:915 ext4_append+0x32c/0x5d0 fs/ext4/namei.c:83 ext4_init_new_dir+0x230/0x8f0 fs/ext4/namei.c:2971 ext4_mkdir+0x4b9/0xc00 fs/ext4/namei.c:3017 vfs_mkdir+0x2f9/0x500 fs/namei.c:4324 do_mkdirat+0x273/0x3f0 fs/namei.c:4357 Memory state around the buggy address: ffff88807e446700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807e446780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807e446800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e446880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e446900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================