KASAN: use-after-free Read in tcf_block

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-4.19	KASAN: use-after-free Read in tcf_block_put (2)				3	873d	904d	0/1	auto-closed as invalid on 2022/04/03 08:44
linux-4.19	KASAN: use-after-free Read in tcf_block_put (3)				2	449d	558d	0/1	upstream: reported on 2022/10/14 14:10
2097051 pages RAM
0 pages HighMem/MovableOnly
369638 pages reserved
0 pages cma reserved
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BUG: KASAN: use-after-free in tcf_block_put+0xf6/0x100 net/sched/cls_api.c:797
Read of size 8 at addr ffff8880583d9ce0 by task syz-executor.0/26979

CPU: 1 PID: 26979 Comm: syz-executor.0 Not tainted 4.19.171-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+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_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 tcf_block_put+0xf6/0x100 net/sched/cls_api.c:797
 cake_destroy+0x3f/0x80 net/sched/sch_cake.c:2630
 qdisc_create+0xb70/0x1130 net/sched/sch_api.c:1204
 tc_modify_qdisc+0x50d/0x1a80 net/sched/sch_api.c:1572
 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115
 __sys_sendmsg net/socket.c:2153 [inline]
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45e219
Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f0938bacc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045e219
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003
RBP: 00007f0938bacca0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000f
R13: 00007ffd2fe3630f R14: 00007f0938bad9c0 R15: 000000000119bf8c

Allocated by task 26979:
 kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625
 kmalloc include/linux/slab.h:515 [inline]
 kzalloc include/linux/slab.h:709 [inline]
 tcf_block_create net/sched/cls_api.c:505 [inline]
 tcf_block_get_ext+0x26a/0x13b0 net/sched/cls_api.c:680
 tcf_block_get+0xa9/0xf0 net/sched/cls_api.c:742
 cake_init+0x2c9/0xb50 net/sched/sch_cake.c:2663
 qdisc_create+0x579/0x1130 net/sched/sch_api.c:1156
 tc_modify_qdisc+0x50d/0x1a80 net/sched/sch_api.c:1572
 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115
 __sys_sendmsg net/socket.c:2153 [inline]
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 26979:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 tcf_block_put_ext.part.0+0x5a1/0x6e0 net/sched/cls_api.c:784
 tcf_block_put_ext net/sched/cls_api.c:754 [inline]
 tcf_block_put+0xad/0x100 net/sched/cls_api.c:797
 cake_destroy net/sched/sch_cake.c:2630 [inline]
 cake_init+0xa9a/0xb50 net/sched/sch_cake.c:2706
 qdisc_create+0x579/0x1130 net/sched/sch_api.c:1156
 tc_modify_qdisc+0x50d/0x1a80 net/sched/sch_api.c:1572
 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115
 __sys_sendmsg net/socket.c:2153 [inline]
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
 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 ffff8880583d9cc0
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 32 bytes inside of
 128-byte region [ffff8880583d9cc0, ffff8880583d9d40)
The buggy address belongs to the page:
page:ffffea000160f640 count:1 mapcount:0 mapping:ffff88813bff0640 index:0x0
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffffea000122e648 ffff88813bff1548 ffff88813bff0640
raw: 0000000000000000 ffff8880583d9000 0000000100000015 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880583d9b80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff8880583d9c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880583d9c80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                       ^
 ffff8880583d9d00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880583d9d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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