================================================================== BUG: KASAN: slab-out-of-bounds in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] BUG: KASAN: slab-out-of-bounds in atomic_fetch_add_unless include/linux/atomic-fallback.h:1086 [inline] BUG: KASAN: slab-out-of-bounds in atomic_add_unless include/linux/atomic-fallback.h:1111 [inline] BUG: KASAN: slab-out-of-bounds in atomic_inc_not_zero include/linux/atomic-fallback.h:1127 [inline] BUG: KASAN: slab-out-of-bounds in dst_hold_safe include/net/dst.h:297 [inline] BUG: KASAN: slab-out-of-bounds in ip6_hold_safe+0xad/0x380 net/ipv6/route.c:1046 Read of size 4 at addr ffff88808ebb6988 by task syz-executor.0/21487 CPU: 1 PID: 21487 Comm: syz-executor.0 Not tainted 5.2.0-rc3+ #50 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_read+0x11/0x20 mm/kasan/common.c:94 atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] atomic_fetch_add_unless include/linux/atomic-fallback.h:1086 [inline] atomic_add_unless include/linux/atomic-fallback.h:1111 [inline] atomic_inc_not_zero include/linux/atomic-fallback.h:1127 [inline] dst_hold_safe include/net/dst.h:297 [inline] ip6_hold_safe+0xad/0x380 net/ipv6/route.c:1046 rt6_get_pcpu_route net/ipv6/route.c:1273 [inline] ip6_pol_route+0x339/0x1050 net/ipv6/route.c:1952 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2128 fib6_rule_lookup+0x279/0x5a0 net/ipv6/fib6_rules.c:120 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2157 ip6_route_output include/net/ip6_route.h:89 [inline] ip6_dst_lookup_tail+0xd10/0x1b30 net/ipv6/ip6_output.c:962 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1090 ip6_datagram_dst_update+0x5d8/0xc20 net/ipv6/datagram.c:87 __ip6_datagram_connect+0x5e9/0x1390 net/ipv6/datagram.c:246 ip6_datagram_connect+0x30/0x50 net/ipv6/datagram.c:269 ip6_datagram_connect_v6_only+0x69/0x90 net/ipv6/datagram.c:281 inet_dgram_connect+0x14a/0x2d0 net/ipv4/af_inet.c:571 __sys_connect+0x264/0x330 net/socket.c:1834 __do_sys_connect net/socket.c:1845 [inline] __se_sys_connect net/socket.c:1842 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1842 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fe488aeec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 000000000000001c RSI: 0000000020000240 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe488aef6d4 R13: 00000000004bf7b5 R14: 00000000004d0f38 R15: 00000000ffffffff Allocated by task 11102: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503 kmem_cache_alloc_trace+0x151/0x750 mm/slab.c:3555 kmalloc include/linux/slab.h:547 [inline] kzalloc include/linux/slab.h:742 [inline] kernfs_iop_get_link fs/kernfs/symlink.c:136 [inline] kernfs_iop_get_link+0x6a/0x680 fs/kernfs/symlink.c:127 vfs_readlink+0x201/0x3e0 fs/namei.c:4734 do_readlinkat+0x2ab/0x320 fs/stat.c:411 __do_sys_readlink fs/stat.c:432 [inline] __se_sys_readlink fs/stat.c:429 [inline] __x64_sys_readlink+0x78/0xb0 fs/stat.c:429 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 11102: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kfree+0xcf/0x220 mm/slab.c:3755 kfree_link+0x16/0x20 fs/libfs.c:1108 do_delayed_call include/linux/delayed_call.h:28 [inline] vfs_readlink+0x16e/0x3e0 fs/namei.c:4739 do_readlinkat+0x2ab/0x320 fs/stat.c:411 __do_sys_readlink fs/stat.c:432 [inline] __se_sys_readlink fs/stat.c:429 [inline] __x64_sys_readlink+0x78/0xb0 fs/stat.c:429 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88808ebb6bc0 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 568 bytes to the left of 4096-byte region [ffff88808ebb6bc0, ffff88808ebb7bc0) The buggy address belongs to the page: page:ffffea00023aed80 refcount:1 mapcount:0 mapping:ffff8880aa400dc0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea00024b1d08 ffffea0002418188 ffff8880aa400dc0 raw: 0000000000000000 ffff88808ebb6bc0 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808ebb6880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808ebb6900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88808ebb6980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88808ebb6a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808ebb6a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================