Hello, syzbot found the following issue on: HEAD commit: 171d4ff7 Merge tag 'mmc-v5.9-rc4-2' of git://git.kernel.or.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=105fbac5900000 kernel config: https://syzkaller.appspot.com/x/.config?x=af502ec9a451c9fc dashboard link: https://syzkaller.appspot.com/bug?extid=9f43bb6a66ff96a21931 compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13cb8f8b900000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12af2c81900000 The issue was bisected to: commit 974e6f02e27e1b46c6c5e600e70ced25079f73eb Author: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx> Date: Mon Aug 1 09:54:35 2016 +0000 iio: cros_ec_sensors_core: Add common functions for the ChromeOS EC Sensor Hub. bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11fe49d3900000 final oops: https://syzkaller.appspot.com/x/report.txt?x=13fe49d3900000 console output: https://syzkaller.appspot.com/x/log.txt?x=15fe49d3900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9f43bb6a66ff96a21931@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 974e6f02e27e ("iio: cros_ec_sensors_core: Add common functions for the ChromeOS EC Sensor Hub.") netlink: 32 bytes leftover after parsing attributes in process `syz-executor211'. ================================================================== BUG: KASAN: use-after-free in tcf_action_destroy net/sched/act_api.c:724 [inline] BUG: KASAN: use-after-free in tcf_action_init+0x231/0x3d0 net/sched/act_api.c:1058 Read of size 8 at addr ffff888097225c00 by task syz-executor211/7086 CPU: 0 PID: 7086 Comm: syz-executor211 Not tainted 5.9.0-rc6-syzkaller #0 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+0x1d6/0x29e lib/dump_stack.c:118 print_address_description+0x66/0x620 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report+0x132/0x1d0 mm/kasan/report.c:530 tcf_action_destroy net/sched/act_api.c:724 [inline] tcf_action_init+0x231/0x3d0 net/sched/act_api.c:1058 tcf_action_add net/sched/act_api.c:1451 [inline] tc_ctl_action+0x2c7/0x7e0 net/sched/act_api.c:1504 rtnetlink_rcv_msg+0x889/0xd40 net/core/rtnetlink.c:5563 netlink_rcv_skb+0x190/0x3a0 net/netlink/af_netlink.c:2470 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x786/0x940 net/netlink/af_netlink.c:1330 netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2353 ___sys_sendmsg net/socket.c:2407 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2440 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x44abe9 Code: e8 dc 13 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 cb 0b fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f842a305ce8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000006e0c48 RCX: 000000000044abe9 RDX: 0000000000000000 RSI: 0000000020002980 RDI: 0000000000000003 RBP: 00000000006e0c40 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006e0c4c R13: 00007ffcf73121ef R14: 00007f842a3069c0 R15: 00000000006e0c4c Allocated by task 7086: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0x100/0x130 mm/kasan/common.c:461 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x205/0x300 mm/slab.c:3664 kmalloc include/linux/slab.h:559 [inline] kzalloc+0x16/0x30 include/linux/slab.h:666 tcf_idr_create+0x56/0x5e0 net/sched/act_api.c:408 tcf_connmark_init+0x230/0x7d0 net/sched/act_connmark.c:126 tcf_action_init_1+0x7dc/0xce0 net/sched/act_api.c:984 tcf_action_init+0x114/0x3d0 net/sched/act_api.c:1043 tcf_action_add net/sched/act_api.c:1451 [inline] tc_ctl_action+0x2c7/0x7e0 net/sched/act_api.c:1504 rtnetlink_rcv_msg+0x889/0xd40 net/core/rtnetlink.c:5563 netlink_rcv_skb+0x190/0x3a0 net/netlink/af_netlink.c:2470 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x786/0x940 net/netlink/af_netlink.c:1330 netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2353 ___sys_sendmsg net/socket.c:2407 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2440 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 7088: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track+0x3d/0x70 mm/kasan/common.c:56 kasan_set_free_info+0x17/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xdd/0x110 mm/kasan/common.c:422 __cache_free mm/slab.c:3418 [inline] kfree+0x113/0x200 mm/slab.c:3756 tcf_idr_release_unsafe net/sched/act_api.c:284 [inline] tcf_del_walker net/sched/act_api.c:310 [inline] tcf_generic_walker+0x6f8/0xbc0 net/sched/act_api.c:339 tca_action_flush net/sched/act_api.c:1278 [inline] tca_action_gd+0x135a/0x18f0 net/sched/act_api.c:1385 tc_ctl_action+0x395/0x7e0 net/sched/act_api.c:1512 rtnetlink_rcv_msg+0x889/0xd40 net/core/rtnetlink.c:5563 netlink_rcv_skb+0x190/0x3a0 net/netlink/af_netlink.c:2470 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x786/0x940 net/netlink/af_netlink.c:1330 netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2353 ___sys_sendmsg net/socket.c:2407 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2440 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888097225c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes inside of 512-byte region [ffff888097225c00, ffff888097225e00) The buggy address belongs to the page: page:00000000598892c8 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x97225 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00028423c8 ffffea00028bbc48 ffff8880aa440600 raw: 0000000000000000 ffff888097225000 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888097225b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888097225b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888097225c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888097225c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888097225d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
