syzbot


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

Status: fixed on 2024/05/22 23:16
Subsystems: isdn4linux
[Documentation on labels]
Fix commit: 138b787804f4 mISDN: fix MISDN_TIME_STAMP handling
First crash: 45d, last: 45d

Sample crash report:
==================================================================
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 data_sock_setsockopt+0x46c/0x4cc drivers/isdn/mISDN/socket.c:417
Read of size 4 at addr ffff0000c6d54083 by task syz-executor406/6167

CPU: 1 PID: 6167 Comm: syz-executor406 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
 __asan_report_load_n_noabort+0x1c/0x28 mm/kasan/report_generic.c:391
 copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
 copy_from_sockptr include/linux/sockptr.h:55 [inline]
 data_sock_setsockopt+0x46c/0x4cc drivers/isdn/mISDN/socket.c:417
 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 6167:
 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]
 __cgroup_bpf_run_filter_setsockopt+0xa94/0xd1c kernel/bpf/cgroup.c:1872
 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 ffff0000c6d54080
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 2 bytes to the right of
 allocated 1-byte region [ffff0000c6d54080, ffff0000c6d54081)

The buggy address belongs to the physical page:
page:000000009dca0a37 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106d54
flags: 0x5ffc00000000800(slab|node=0|zone=2|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 05ffc00000000800 ffff0000c0001280 fffffdffc31a6e80 dead000000000002
raw: 0000000000000000 0000000080800080 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000c6d53f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000c6d54000: 06 fc fc fc 06 fc fc fc 06 fc fc fc 05 fc fc fc
>ffff0000c6d54080: 01 fc fc fc 00 fc fc fc 06 fc fc fc 06 fc fc fc
                   ^
 ffff0000c6d54100: 06 fc fc fc 05 fc fc fc fa fc fc fc fa fc fc fc
 ffff0000c6d54180: 06 fc fc fc 06 fc fc fc 06 fc fc fc 05 fc fc fc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/08 06:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 707081b61156 ca620dd8 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in data_sock_setsockopt
2024/04/08 05:23 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 707081b61156 ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in data_sock_setsockopt
* Struck through repros no longer work on HEAD.