syzbot


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

Status: fixed on 2024/05/22 23:46
Subsystems: bridge netfilter
[Documentation on labels]
Fix commit: 0c83842df40f netfilter: validate user input for expected length
First crash: 47d, last: 47d

Sample crash report:
UDPLite: UDP-Lite is deprecated and scheduled to be removed in 2025, please contact the netdev mailing list
==================================================================
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline]
BUG: KASAN: slab-out-of-bounds in update_counters+0xec/0x2e8 net/bridge/netfilter/ebtables.c:1426
Read of size 120 at addr ffff0000d597e300 by task syz-executor427/6170

CPU: 0 PID: 6170 Comm: syz-executor427 Not tainted 6.8.0-rc7-syzkaller-g707081b61156 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x178/0x518 mm/kasan/report.c:488
 kasan_report+0xd8/0x138 mm/kasan/report.c:601
 kasan_check_range+0x254/0x294 mm/kasan/generic.c:189
 __asan_memcpy+0x3c/0x84 mm/kasan/shadow.c:105
 copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
 copy_from_sockptr include/linux/sockptr.h:55 [inline]
 update_counters+0xec/0x2e8 net/bridge/netfilter/ebtables.c:1426
 do_ebt_set_ctl+0x498/0x13ec
 nf_setsockopt+0x270/0x290 net/netfilter/nf_sockopt.c:101
 ip_setsockopt+0x118/0x128 net/ipv4/ip_sockglue.c:1420
 udp_setsockopt+0xb8/0xd0 net/ipv4/udp.c:2783
 sock_common_setsockopt+0xb0/0xcc net/core/sock.c:3715
 do_sock_setsockopt+0x2a0/0x4e0 net/socket.c:2311
 __sys_setsockopt+0x128/0x1a8 net/socket.c:2334
 __do_sys_setsockopt net/socket.c:2343 [inline]
 __se_sys_setsockopt net/socket.c:2340 [inline]
 __arm64_sys_setsockopt+0xb8/0xd4 net/socket.c:2340
 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598

Allocated by task 6170:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:68
 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:575
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slub.c:3981 [inline]
 __kmalloc+0x2bc/0x5d4 mm/slub.c:3994
 kmalloc include/linux/slab.h:594 [inline]
 kzalloc include/linux/slab.h:711 [inline]
 sockopt_alloc_buf kernel/bpf/cgroup.c:1779 [inline]
 __cgroup_bpf_run_filter_setsockopt+0x240/0xd1c kernel/bpf/cgroup.c:1820
 do_sock_setsockopt+0x498/0x4e0 net/socket.c:2293
 __sys_setsockopt+0x128/0x1a8 net/socket.c:2334
 __do_sys_setsockopt net/socket.c:2343 [inline]
 __se_sys_setsockopt net/socket.c:2340 [inline]
 __arm64_sys_setsockopt+0xb8/0xd4 net/socket.c:2340
 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598

The buggy address belongs to the object at ffff0000d597e300
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes inside of
 allocated 33-byte region [ffff0000d597e300, ffff0000d597e321)

The buggy address belongs to the physical page:
page:000000007709c76c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11597e
flags: 0x5ffc00000000800(slab|node=0|zone=2|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 05ffc00000000800 ffff0000c0001640 fffffdffc30ef140 dead000000000006
raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000d597e200: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff0000d597e280: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
>ffff0000d597e300: 00 00 00 00 01 fc fc fc fc fc fc fc fc fc fc fc
                               ^
 ffff0000d597e380: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff0000d597e400: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/06 05:13 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 707081b61156 18ea8213 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in update_counters
2024/04/06 04:46 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 707081b61156 18ea8213 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in update_counters
2024/04/06 04:46 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 707081b61156 18ea8213 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in update_counters
* Struck through repros no longer work on HEAD.