bisecting fixing commit since 5b7a52cd2eef952cee8a72512ef370bcdef46636
building syzkaller on f24824d3d54060a7d878eeb35c47f85dab84966a
testing commit 5b7a52cd2eef952cee8a72512ef370bcdef46636 with gcc (GCC) 8.1.0
kernel signature: 7969781daf0a432526a52d91f6d6d2435bf112f94a643e2b5221db40138290a8
run #0: crashed: general protection fault in __tcf_idr_release
run #1: crashed: general protection fault in __tcf_idr_release
run #2: crashed: KASAN: use-after-free Read in tcf_action_destroy
run #3: crashed: general protection fault in __tcf_idr_release
run #4: crashed: general protection fault in __tcf_idr_release
run #5: crashed: general protection fault in __tcf_idr_release
run #6: crashed: general protection fault in __tcf_idr_release
run #7: crashed: general protection fault in __tcf_idr_release
run #8: crashed: general protection fault in __tcf_idr_release
run #9: crashed: KASAN: stack-out-of-bounds Read in tcf_action_destroy
testing current HEAD 2d2791fce891fc20709232d49a6bae075b9a77f8
testing commit 2d2791fce891fc20709232d49a6bae075b9a77f8 with gcc (GCC) 8.1.0
kernel signature: e3cc085ffaf34c186fed077c55491efaa174168928b5343a7dc176e6b7a213ce
run #0: crashed: BUG: unable to handle kernel paging request in tcf_action_destroy
run #1: crashed: general protection fault in __tcf_idr_release
run #2: crashed: general protection fault in __tcf_idr_release
run #3: crashed: general protection fault in __tcf_idr_release
run #4: crashed: BUG: unable to handle kernel paging request in tcf_action_destroy
run #5: crashed: general protection fault in __tcf_idr_release
run #6: crashed: KASAN: stack-out-of-bounds Read in tcf_action_destroy
run #7: crashed: general protection fault in __tcf_idr_release
run #8: crashed: BUG: unable to handle kernel paging request in tcf_action_destroy
run #9: crashed: general protection fault in __tcf_idr_release
revisions tested: 2, total time: 24m18.801294147s (build: 17m27.586803029s, test: 6m7.798799653s)
the crash still happens on HEAD
commit msg: Linux 4.14.217
crash: general protection fault in __tcf_idr_release
netlink: 32 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 32 bytes leftover after parsing attributes in process `syz-executor.5'.
netlink: 32 bytes leftover after parsing attributes in process `syz-executor.0'.
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 14214 Comm: syz-executor.2 Not tainted 4.14.217-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8881da632280 task.stack: ffff8881cc330000
RIP: 0010:__tcf_idr_release+0xeb/0x1c0 net/sched/act_api.c:99
RSP: 0018:ffff8881cc3373e0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881c5eff680 RCX: ffff8881c5eff680
RDX: 03fffe220717bfe5 RSI: 0000000000000000 RDI: 1ffff11038bdff2a
RBP: ffff8881cc337400 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8881da632280 R12: 0000000000000000
R13: 1ffff11038bdfee2 R14: 0000000000000001 R15: 0000000000000000
FS:  00007f3b1fe53700(0000) GS:ffff8881f6500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555830a03238 CR3: 00000001ed701002 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcf_action_destroy+0xbf/0x160 net/sched/act_api.c:527
 tcf_action_init+0x335/0x460 net/sched/act_api.c:769
 tcf_action_add net/sched/act_api.c:1079 [inline]
 tc_ctl_action+0x3c4/0x580 net/sched/act_api.c:1131
 rtnetlink_rcv_msg+0x34c/0x9e0 net/core/rtnetlink.c:4316
 netlink_rcv_skb+0x12f/0x3b0 net/netlink/af_netlink.c:2433
 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4328
 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x40b/0x610 net/netlink/af_netlink.c:1313
 netlink_sendmsg+0x657/0xc60 net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xac/0xf0 net/socket.c:656
 ___sys_sendmsg+0x625/0x920 net/socket.c:2062
 __sys_sendmsg+0xc1/0x140 net/socket.c:2096
 SYSC_sendmsg net/socket.c:2107 [inline]
 SyS_sendmsg+0xd/0x20 net/socket.c:2103
 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45deb9
RSP: 002b:00007f3b1fe52c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000002e680 RCX: 000000000045deb9
RDX: 0000000000000000 RSI: 0000000020002980 RDI: 0000000000000003
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffcff283acf R14: 00007f3b1fe539c0 R15: 000000000118bf2c
Code: ff df 48 89 da 48 c1 ea 03 80 3c 02 00 0f 85 de 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 2b 49 8d 7d 48 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 b2 00 00 00 49 8b 45 48 48 85 c0 74 09 41 0f 
RIP: __tcf_idr_release+0xeb/0x1c0 net/sched/act_api.c:99 RSP: ffff8881cc3373e0
---[ end trace f3f48961b78527a5 ]---