================================================================== BUG: KASAN: use-after-free in vxlan_vnifilter_dump_dev+0x9a0/0xb40 drivers/net/vxlan/vxlan_vnifilter.c:349 Read of size 4 at addr ffff888076738e70 by task syz-executor137/3687 CPU: 0 PID: 3687 Comm: syz-executor137 Tainted: G W 5.17.0-syzkaller-10107-gd717e4cae0fe #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 vxlan_vnifilter_dump_dev+0x9a0/0xb40 drivers/net/vxlan/vxlan_vnifilter.c:349 vxlan_vnifilter_dump+0x3ff/0x650 drivers/net/vxlan/vxlan_vnifilter.c:428 netlink_dump+0x4b5/0xb70 net/netlink/af_netlink.c:2270 __netlink_dump_start+0x647/0x900 net/netlink/af_netlink.c:2375 netlink_dump_start include/linux/netlink.h:245 [inline] rtnetlink_rcv_msg+0x70c/0xb80 net/core/rtnetlink.c:5953 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2496 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 ____sys_sendmsg+0x6e2/0x800 net/socket.c:2413 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f873f8acf49 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffced20ede8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f873f8acf49 RDX: 0000000000000000 RSI: 00000000200003c0 RDI: 0000000000000004 RBP: 0000000000000000 R08: 00007ffced20ee31 R09: 00007ffced20ee31 R10: 00007ffced20ee31 R11: 0000000000000246 R12: 00007ffced20ee30 R13: 00007ffced20ee20 R14: 00007ffced20ee10 R15: 00007ffced20ee50 Allocated by task 3538: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524 kmalloc include/linux/slab.h:586 [inline] tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x140 security/security.c:1350 vfs_getattr fs/stat.c:157 [inline] vfs_statx+0x16a/0x390 fs/stat.c:232 vfs_fstatat+0x8c/0xb0 fs/stat.c:255 __do_sys_newfstatat+0x91/0x110 fs/stat.c:426 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 3538: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kfree+0xd6/0x4d0 mm/slub.c:4552 tomoyo_realpath_from_path+0x191/0x620 security/tomoyo/realpath.c:291 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x140 security/security.c:1350 vfs_getattr fs/stat.c:157 [inline] vfs_statx+0x16a/0x390 fs/stat.c:232 vfs_fstatat+0x8c/0xb0 fs/stat.c:255 __do_sys_newfstatat+0x91/0x110 fs/stat.c:426 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff888076738000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 3696 bytes inside of 4096-byte region [ffff888076738000, ffff888076739000) The buggy address belongs to the physical page: page:ffffea0001d9ce00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x76738 head:ffffea0001d9ce00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010c42140 raw: 0000000000000000 0000000000040004 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2967, tgid 2967 (udevd), ts 15855511621, free_ts 12004225701 prep_new_page mm/page_alloc.c:2438 [inline] get_page_from_freelist+0xba2/0x3df0 mm/page_alloc.c:4179 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5405 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2262 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x8df/0xf20 mm/slub.c:3005 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092 slab_alloc_node mm/slub.c:3183 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x318/0x350 mm/slub.c:4410 kmalloc include/linux/slab.h:586 [inline] tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x140 security/security.c:1350 vfs_getattr fs/stat.c:157 [inline] vfs_statx+0x16a/0x390 fs/stat.c:232 vfs_fstatat+0x8c/0xb0 fs/stat.c:255 __do_sys_newfstatat+0x91/0x110 fs/stat.c:426 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1353 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1403 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3420 free_contig_range+0xb1/0x180 mm/page_alloc.c:9414 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1018 debug_vm_pgtable+0x2a50/0x2ae2 mm/debug_vm_pgtable.c:1332 do_one_initcall+0x103/0x650 init/main.c:1298 do_initcall_level init/main.c:1371 [inline] do_initcalls init/main.c:1387 [inline] do_basic_setup init/main.c:1406 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1613 kernel_init+0x1a/0x1d0 init/main.c:1502 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Memory state around the buggy address: ffff888076738d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076738d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888076738e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888076738e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076738f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================