================================================================== BUG: KASAN: stack-out-of-bounds in ip6mr_ioctl+0xba3/0xcb0 net/ipv6/ip6mr.c:1917 Read of size 16 at addr ffffc900033f7b68 by task syz-executor.5/12080 CPU: 1 PID: 12080 Comm: syz-executor.5 Not tainted 6.4.0-rc7-next-20230621-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:364 print_report mm/kasan/report.c:475 [inline] kasan_report+0x11d/0x130 mm/kasan/report.c:588 ip6mr_ioctl+0xba3/0xcb0 net/ipv6/ip6mr.c:1917 rawv6_ioctl+0x4e/0x1e0 net/ipv6/raw.c:1143 sock_ioctl_out net/core/sock.c:4186 [inline] sk_ioctl+0x151/0x440 net/core/sock.c:4214 inet6_ioctl+0x1b8/0x290 net/ipv6/af_inet6.c:582 sock_do_ioctl+0xcc/0x230 net/socket.c:1190 sock_ioctl+0x1f8/0x680 net/socket.c:1307 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x19d/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6ac168c389 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6ac24bf168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6ac17abf80 RCX: 00007f6ac168c389 RDX: 0000000020000080 RSI: 00000000000089e1 RDI: 0000000000000003 RBP: 00007f6ac16d7493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcc620d8df R14: 00007f6ac24bf300 R15: 0000000000022000 The buggy address belongs to stack of task syz-executor.5/12080 and is located at offset 40 in frame: sk_ioctl+0x0/0x440 net/core/sock.c:4172 This frame has 2 objects: [32, 36) 'karg' [48, 88) 'buffer' The buggy address belongs to the virtual mapping at [ffffc900033f0000, ffffc900033f9000) created by: kernel_clone+0xeb/0x890 kernel/fork.c:2911 The buggy address belongs to the physical page: page:ffffea000062f900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x18be4 memcg:ffff888019b22802 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff ffff888019b22802 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 5077, tgid 5077 (syz-executor.3), ts 822173780675, free_ts 822164772545 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1570 prep_new_page mm/page_alloc.c:1577 [inline] get_page_from_freelist+0xfc2/0x2b00 mm/page_alloc.c:3257 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4513 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2279 vm_area_alloc_pages mm/vmalloc.c:3059 [inline] __vmalloc_area_node mm/vmalloc.c:3135 [inline] __vmalloc_node_range+0xb73/0x14b0 mm/vmalloc.c:3316 alloc_thread_stack_node kernel/fork.c:309 [inline] dup_task_struct kernel/fork.c:1112 [inline] copy_process+0x13bb/0x75c0 kernel/fork.c:2329 kernel_clone+0xeb/0x890 kernel/fork.c:2911 __do_sys_clone+0xba/0x100 kernel/fork.c:3054 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1161 [inline] free_unref_page_prepare+0x4dd/0xb90 mm/page_alloc.c:2384 free_unref_page_list+0xe3/0xa70 mm/page_alloc.c:2525 release_pages+0xcd8/0x1380 mm/swap.c:1042 tlb_batch_pages_flush+0xa8/0x1a0 mm/mmu_gather.c:97 tlb_flush_mmu_free mm/mmu_gather.c:292 [inline] tlb_flush_mmu mm/mmu_gather.c:299 [inline] tlb_finish_mmu+0x14b/0x7e0 mm/mmu_gather.c:391 exit_mmap+0x2cd/0x960 mm/mmap.c:3140 __mmput+0x128/0x4c0 kernel/fork.c:1347 mmput+0x60/0x70 kernel/fork.c:1369 exit_mm kernel/exit.c:567 [inline] do_exit+0x9a7/0x2a30 kernel/exit.c:861 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024 get_signal+0x249b/0x25f0 kernel/signal.c:2877 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:308 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffffc900033f7a00: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00 ffffc900033f7a80: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc900033f7b00: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 00 00 ^ ffffc900033f7b80: 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 00 ffffc900033f7c00: 00 00 00 f1 f1 f1 f1 f1 f1 00 00 00 00 00 00 00 ==================================================================