================================================================== BUG: KASAN: slab-out-of-bounds in _decode_session6+0xf56/0x1370 net/ipv6/xfrm6_policy.c:137 Read of size 1 at addr ffff8880b27cda96 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load1_noabort+0x88/0x90 mm/kasan/report.c:430 _decode_session6+0xf56/0x1370 net/ipv6/xfrm6_policy.c:137 __xfrm_decode_session+0x5a/0x130 net/xfrm/xfrm_policy.c:2299 xfrm_decode_session include/net/xfrm.h:1238 [inline] vti_tunnel_xmit+0x279/0x1850 net/ipv4/ip_vti.c:326 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [inline] xmit_one net/core/dev.c:3256 [inline] dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272 sch_direct_xmit+0x2d6/0xf70 net/sched/sch_generic.c:332 qdisc_restart net/sched/sch_generic.c:395 [inline] __qdisc_run+0x4d0/0x1640 net/sched/sch_generic.c:403 __dev_xmit_skb net/core/dev.c:3500 [inline] __dev_queue_xmit+0x1518/0x2e00 net/core/dev.c:3807 neigh_output include/net/neighbour.h:501 [inline] ip6_finish_output2+0x113d/0x2290 net/ipv6/ip6_output.c:120 ip6_finish_output+0x89b/0x10f0 net/ipv6/ip6_output.c:192 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x205/0x770 net/ipv6/ip6_output.c:209 dst_output include/net/dst.h:455 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ndisc_send_skb+0xa24/0x1720 net/ipv6/ndisc.c:491 ndisc_send_rs+0x131/0x690 net/ipv6/ndisc.c:685 addrconf_rs_timer+0x384/0x6a0 net/ipv6/addrconf.c:3835 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61 Code: 48 89 df e8 f4 20 7f f9 e9 2e ff ff ff 48 89 df e8 e7 20 7f f9 eb 82 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 14 43 4e 00 fb f4 90 e9 07 00 00 00 0f 00 2d 04 43 4e 00 f4 c3 90 90 41 56 41 55 RSP: 0018:ffffffff89e07d40 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3054 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffffffff89e78904 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff89f18290 R13: 1ffffffff13c0fb2 R14: 0000000000000000 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0x49/0x310 arch/x86/kernel/process.c:557 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x2ec/0x4b0 kernel/sched/idle.c:263 cpu_startup_entry+0xc5/0xe0 kernel/sched/idle.c:369 start_kernel+0x8d6/0x911 init/main.c:736 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 Allocated by task 4696: kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 getname_flags+0xce/0x590 fs/namei.c:140 getname fs/namei.c:211 [inline] __do_sys_unlink fs/namei.c:4112 [inline] __se_sys_unlink fs/namei.c:4110 [inline] __x64_sys_unlink+0x31/0x50 fs/namei.c:4110 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 4696: __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 putname+0xe1/0x120 fs/namei.c:261 do_unlinkat+0x12b/0x660 fs/namei.c:4086 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880b27cc2c0 which belongs to the cache names_cache of size 4096 The buggy address is located 2006 bytes to the right of 4096-byte region [ffff8880b27cc2c0, ffff8880b27cd2c0) The buggy address belongs to the page: page:ffffea0002c9f300 count:1 mapcount:0 mapping:ffff88823b843380 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea0002caca08 ffffea0002450008 ffff88823b843380 raw: 0000000000000000 ffff8880b27cc2c0 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880b27cd980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880b27cda00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880b27cda80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880b27cdb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880b27cdb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 48 89 df mov %rbx,%rdi 3: e8 f4 20 7f f9 callq 0xf97f20fc 8: e9 2e ff ff ff jmpq 0xffffff3b d: 48 89 df mov %rbx,%rdi 10: e8 e7 20 7f f9 callq 0xf97f20fc 15: eb 82 jmp 0xffffff99 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: e9 07 00 00 00 jmpq 0x28 21: 0f 00 2d 14 43 4e 00 verw 0x4e4314(%rip) # 0x4e433c 28: fb sti 29: f4 hlt * 2a: c3 retq <-- trapping instruction 2b: 90 nop 2c: e9 07 00 00 00 jmpq 0x38 31: 0f 00 2d 04 43 4e 00 verw 0x4e4304(%rip) # 0x4e433c 38: f4 hlt 39: c3 retq 3a: 90 nop 3b: 90 nop 3c: 41 56 push %r14 3e: 41 55 push %r13