syzbot


KASAN: slab-out-of-bounds Read in tc_setup_flow_action

Status: upstream: reported C repro on 2025/01/04 22:41
Bug presence: origin:lts
[Documentation on labels]
Reported-by: syzbot+04a3bfe287000b1a5529@syzkaller.appspotmail.com
First crash: 237d, last: 7h00m
Bug presence (2)
Date Name Commit Repro Result
2025/01/06 lts (merge base) a08241812f21 C [report] KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/01/06 upstream (ToT) 9d89551994a4 C Didn't crash
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 KASAN: slab-out-of-bounds Read in tc_setup_flow_action 17 C 1364 6h56m 237d 0/2 upstream: reported C repro on 2025/01/04 22:42

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in is_tcf_tunnel_set include/net/tc_act/tc_tunnel_key.h:33 [inline]
BUG: KASAN: slab-out-of-bounds in tc_setup_flow_action+0x870/0x3240 net/sched/cls_api.c:3625
Read of size 8 at addr ffff8881077a5dc0 by task syz-executor383/288

CPU: 1 PID: 288 Comm: syz-executor383 Not tainted 5.15.189-syzkaller-00079-ga71626bd56a5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0xf1/0x140 mm/kasan/report.c:444
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 is_tcf_tunnel_set include/net/tc_act/tc_tunnel_key.h:33 [inline]
 tc_setup_flow_action+0x870/0x3240 net/sched/cls_api.c:3625
 mall_replace_hw_filter+0x293/0x820 net/sched/cls_matchall.c:100
 mall_change+0x526/0x740 net/sched/cls_matchall.c:235
 tc_new_tfilter+0x12a2/0x1870 net/sched/cls_api.c:2131
 rtnetlink_rcv_msg+0x81b/0xb90 net/core/rtnetlink.c:5641
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2511
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668
 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348
 netlink_sendmsg+0x86a/0xb70 net/netlink/af_netlink.c:1922
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490
 __sys_sendmsg net/socket.c:2519 [inline]
 __do_sys_sendmsg net/socket.c:2528 [inline]
 __se_sys_sendmsg net/socket.c:2526 [inline]
 __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2526
 x64_sys_call+0x4b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb3335877a9
Code: 48 83 c4 28 c3 e8 37 17 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdb6cd2618 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ffdb6cd27e8 RCX: 00007fb3335877a9
RDX: 0000000000000000 RSI: 0000200000000580 RDI: 0000000000000003
RBP: 00007fb3335fa610 R08: 0000000000000004 R09: 00007ffdb6cd27e8
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffdb6cd27d8 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Allocated by task 288:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 ____kasan_kmalloc mm/kasan/common.c:512 [inline]
 __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:521
 kasan_kmalloc include/linux/kasan.h:227 [inline]
 __kmalloc+0x13d/0x2c0 mm/slub.c:4431
 kmalloc include/linux/slab.h:621 [inline]
 kzalloc include/linux/slab.h:747 [inline]
 tcf_idr_create+0x5f/0x790 net/sched/act_api.c:478
 tcf_idr_create_from_flags+0x61/0x70 net/sched/act_api.c:536
 tcf_gact_init+0x346/0x580 net/sched/act_gact.c:102
 tcf_action_init_1+0x3f7/0x6a0 net/sched/act_api.c:1071
 tcf_action_init+0x1e9/0x710 net/sched/act_api.c:1130
 tcf_exts_validate+0x217/0x520 net/sched/cls_api.c:3073
 mall_set_parms+0x48/0x520 net/sched/cls_matchall.c:171
 mall_change+0x45a/0x740 net/sched/cls_matchall.c:229
 tc_new_tfilter+0x12a2/0x1870 net/sched/cls_api.c:2131
 rtnetlink_rcv_msg+0x81b/0xb90 net/core/rtnetlink.c:5641
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2511
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668
 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348
 netlink_sendmsg+0x86a/0xb70 net/netlink/af_netlink.c:1922
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490
 __sys_sendmsg net/socket.c:2519 [inline]
 __do_sys_sendmsg net/socket.c:2528 [inline]
 __se_sys_sendmsg net/socket.c:2526 [inline]
 __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2526
 x64_sys_call+0x4b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff8881077a5d00
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 0 bytes to the right of
 192-byte region [ffff8881077a5d00, ffff8881077a5dc0)
The buggy address belongs to the page:
page:ffffea00041de940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1077a5
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 ffffea00041de280 0000000400000004 ffff888100042c00
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 1214215473, free_ts 0
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611
 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485
 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5795
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1932 [inline]
 new_slab+0xa1/0x4d0 mm/slub.c:1995
 ___slab_alloc+0x381/0x810 mm/slub.c:3028
 __slab_alloc+0x49/0x90 mm/slub.c:3115
 slab_alloc_node mm/slub.c:3206 [inline]
 slab_alloc mm/slub.c:3250 [inline]
 __kmalloc_track_caller+0x169/0x2c0 mm/slub.c:4949
 __do_krealloc mm/slab_common.c:1258 [inline]
 krealloc+0x6a/0x100 mm/slab_common.c:1291
 add_sysfs_param+0xce/0x830 kernel/params.c:651
 kernel_add_sysfs_param+0xb3/0x130 kernel/params.c:812
 param_sysfs_builtin+0x164/0x1e0 kernel/params.c:851
 param_sysfs_init+0x6a/0x70 kernel/params.c:972
 do_one_initcall+0x17f/0x500 init/main.c:1304
 do_initcall_level+0x16f/0x2d0 init/main.c:1377
 do_initcalls+0x50/0xa0 init/main.c:1393
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8881077a5c80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
 ffff8881077a5d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881077a5d80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
                                           ^
 ffff8881077a5e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881077a5e80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
==================================================================

Crashes (1349):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/22 13:42 android13-5.15-lts a71626bd56a5 1555463b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/04/15 13:25 android13-5.15-lts 610bd6013c81 23b969b7 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/01/05 06:43 android13-5.15-lts af461d0249a8 f3558dbf .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/01/04 22:36 android13-5.15-lts af461d0249a8 f3558dbf .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/30 03:18 android13-5.15-lts f32b52534f1d 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/29 01:38 android13-5.15-lts f32b52534f1d d401b9d7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/28 22:38 android13-5.15-lts f32b52534f1d d401b9d7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/28 22:37 android13-5.15-lts f32b52534f1d d401b9d7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/28 14:39 android13-5.15-lts f32b52534f1d e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/28 06:57 android13-5.15-lts f32b52534f1d e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/27 20:26 android13-5.15-lts f32b52534f1d e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/27 00:25 android13-5.15-lts f32b52534f1d e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/26 05:11 android13-5.15-lts f32b52534f1d bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/25 21:30 android13-5.15-lts f32b52534f1d bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/24 17:00 android13-5.15-lts f32b52534f1d bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/24 15:49 android13-5.15-lts f32b52534f1d bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/23 20:58 android13-5.15-lts f32b52534f1d bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/23 06:27 android13-5.15-lts f32b52534f1d bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/22 07:09 android13-5.15-lts f32b52534f1d bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/20 22:14 android13-5.15-lts f32b52534f1d 0b9605c8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/20 17:27 android13-5.15-lts f32b52534f1d 0b9605c8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/19 16:35 android13-5.15-lts f32b52534f1d 254a27c1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/18 16:35 android13-5.15-lts f32b52534f1d 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/17 10:50 android13-5.15-lts f32b52534f1d 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/16 07:37 android13-5.15-lts f32b52534f1d 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/15 22:56 android13-5.15-lts f32b52534f1d 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/15 18:28 android13-5.15-lts f32b52534f1d 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/15 05:25 android13-5.15-lts f32b52534f1d 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/14 15:53 android13-5.15-lts f32b52534f1d 5d8c2ac2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/14 12:27 android13-5.15-lts f32b52534f1d 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/14 05:27 android13-5.15-lts f32b52534f1d 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/12 22:08 android13-5.15-lts f32b52534f1d 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/12 10:57 android13-5.15-lts f32b52534f1d c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/12 06:57 android13-5.15-lts f32b52534f1d c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/11 21:20 android13-5.15-lts f32b52534f1d c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/11 21:20 android13-5.15-lts f32b52534f1d c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/11 14:54 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/11 11:35 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/11 05:33 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/10 17:37 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/10 11:00 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/10 00:14 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/09 08:24 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/09 06:05 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/09 06:05 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/09 04:15 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/09 03:04 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/08/08 16:54 android13-5.15-lts f32b52534f1d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
2025/01/04 22:20 android13-5.15-lts af461d0249a8 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in tc_setup_flow_action
* Struck through repros no longer work on HEAD.