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KASAN: slab-out-of-bounds Read in cfg80211_wext_freq (2)

Status: upstream: reported on 2024/08/17 19:12
Subsystems: wireless
[Documentation on labels]
Reported-by: syzbot+ad5a1b5c1c112c61fc6f@syzkaller.appspotmail.com
First crash: 99d, last: 99d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [wireless?] KASAN: slab-out-of-bounds Read in cfg80211_wext_freq (2) 0 (1) 2024/08/17 19:12
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in cfg80211_wext_freq wireless C inconclusive 133 149d 175d 26/28 fixed on 2024/07/09 19:14
linux-6.1 KASAN: slab-out-of-bounds Read in cfg80211_wext_freq origin:lts-only C done 48 119d 165d 0/3 upstream: reported C repro on 2024/06/09 04:12
linux-5.15 KASAN: slab-out-of-bounds Read in cfg80211_wext_freq origin:lts-only C error 71 118d 160d 0/3 upstream: reported C repro on 2024/06/13 10:59

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in cfg80211_wext_freq+0x170/0x1ac net/wireless/wext-compat.c:238
Read of size 2 at addr ffff0000cbece140 by task syz.3.369/7789

CPU: 1 PID: 7789 Comm: syz.3.369 Tainted: G        W          6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:317
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x198/0x538 mm/kasan/report.c:488
 kasan_report+0xd8/0x138 mm/kasan/report.c:601
 __asan_report_load2_noabort+0x20/0x2c mm/kasan/report_generic.c:379
 cfg80211_wext_freq+0x170/0x1ac net/wireless/wext-compat.c:238
 cfg80211_wext_siwscan+0x438/0xef0 net/wireless/scan.c:3447
 ioctl_standard_iw_point+0x7f0/0xdc4 net/wireless/wext-core.c:867
 ioctl_standard_call+0xcc/0x264 net/wireless/wext-core.c:1052
 wext_ioctl_dispatch+0x1b4/0x534 net/wireless/wext-core.c:1016
 wext_handle_ioctl+0x1f8/0x3f4 net/wireless/wext-core.c:1077
 sock_ioctl+0x15c/0x838 net/socket.c:1275
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl fs/ioctl.c:893 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893
 __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 7789:
 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:565
 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:4121 [inline]
 __kmalloc_noprof+0x2a0/0x494 mm/slub.c:4134
 kmalloc_noprof include/linux/slab.h:664 [inline]
 kzalloc_noprof include/linux/slab.h:778 [inline]
 ioctl_standard_iw_point+0x3b8/0xdc4 net/wireless/wext-core.c:828
 ioctl_standard_call+0xcc/0x264 net/wireless/wext-core.c:1052
 wext_ioctl_dispatch+0x1b4/0x534 net/wireless/wext-core.c:1016
 wext_handle_ioctl+0x1f8/0x3f4 net/wireless/wext-core.c:1077
 sock_ioctl+0x15c/0x838 net/socket.c:1275
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl fs/ioctl.c:893 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893
 __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 ffff0000cbece000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 4 bytes to the right of
 allocated 316-byte region [ffff0000cbece000, ffff0000cbece13c)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10becc
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff)
page_type: 0xffffefff(slab)
raw: 05ffc00000000040 ffff0000c0001c80 0000000000000000 dead000000000001
raw: 0000000000000000 0000000080100010 00000001ffffefff 0000000000000000
head: 05ffc00000000040 ffff0000c0001c80 0000000000000000 dead000000000001
head: 0000000000000000 0000000080100010 00000001ffffefff 0000000000000000
head: 05ffc00000000002 fffffdffc32fb301 ffffffffffffffff 0000000000000000
head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000cbece000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff0000cbece080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff0000cbece100: 00 00 00 00 00 00 00 04 fc fc fc fc fc fc fc fc
                                           ^
 ffff0000cbece180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000cbece200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in net/wireless/scan.c:3445:8
index 33 is out of range for type 'struct iw_freq[32]'
CPU: 1 PID: 7789 Comm: syz.3.369 Tainted: G    B   W          6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:317
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:114
 dump_stack+0x1c/0x28 lib/dump_stack.c:123
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_out_of_bounds+0xf8/0x148 lib/ubsan.c:429
 cfg80211_wext_siwscan+0x4a8/0xef0 net/wireless/scan.c:3445
 ioctl_standard_iw_point+0x7f0/0xdc4 net/wireless/wext-core.c:867
 ioctl_standard_call+0xcc/0x264 net/wireless/wext-core.c:1052
 wext_ioctl_dispatch+0x1b4/0x534 net/wireless/wext-core.c:1016
 wext_handle_ioctl+0x1f8/0x3f4 net/wireless/wext-core.c:1077
 sock_ioctl+0x15c/0x838 net/socket.c:1275
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl fs/ioctl.c:893 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893
 __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
---[ end trace ]---

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/14 00:12 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8867bbd4a056 f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in cfg80211_wext_freq
2024/08/14 00:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8867bbd4a056 f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in cfg80211_wext_freq
2024/08/13 23:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8867bbd4a056 f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in cfg80211_wext_freq
2024/08/13 22:33 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8867bbd4a056 f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in cfg80211_wext_freq
2024/08/13 19:09 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8867bbd4a056 f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in cfg80211_wext_freq
2024/08/13 19:09 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8867bbd4a056 f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-out-of-bounds Read in cfg80211_wext_freq
* Struck through repros no longer work on HEAD.