[syzbot] KASAN: use-after-free Read in rtl8712_dl_fw

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8ef1e58783b9 usb: typec: STUSB160X should select REGMAP_I2C
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=1106dcfb300000
kernel config: https://syzkaller.appspot.com/x/.config?x=c27d285bdb7457e2
dashboard link: https://syzkaller.appspot.com/bug?extid=c55162be492189fb4f51
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12725770b00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1168c158b00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c55162...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in rtl871x_open_fw drivers/staging/rtl8712/hal_init.c:83 [inline]
BUG: KASAN: use-after-free in rtl8712_dl_fw+0xd95/0xe10 drivers/staging/rtl8712/hal_init.c:170
Read of size 8 at addr ffff88810e25c9c0 by task dhcpcd/1204

CPU: 0 PID: 1204 Comm: dhcpcd Not tainted 5.15.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:256
__kasan_report mm/kasan/report.c:442 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
rtl871x_open_fw drivers/staging/rtl8712/hal_init.c:83 [inline]
rtl8712_dl_fw+0xd95/0xe10 drivers/staging/rtl8712/hal_init.c:170
rtl8712_hal_init drivers/staging/rtl8712/hal_init.c:330 [inline]
rtl871x_hal_init+0xae/0x180 drivers/staging/rtl8712/hal_init.c:394
netdev_open+0xe6/0x6c0 drivers/staging/rtl8712/os_intfs.c:380
__dev_open+0x2bc/0x4d0 net/core/dev.c:1484
__dev_change_flags+0x583/0x750 net/core/dev.c:8761
dev_change_flags+0x93/0x170 net/core/dev.c:8832
devinet_ioctl+0x15d1/0x1ca0 net/ipv4/devinet.c:1142
inet_ioctl+0x1e6/0x320 net/ipv4/af_inet.c:971
sock_do_ioctl+0xcc/0x230 net/socket.c:1118
sock_ioctl+0x2f1/0x640 net/socket.c:1235
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7ff4004a20e7
Code: 3c 1c e8 1c ff ff ff 85 c0 79 87 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 61 9d 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007fffba0f8738 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff4003b46c8 RCX: 00007ff4004a20e7
RDX: 00007fffba108928 RSI: 0000000000008914 RDI: 0000000000000005
RBP: 00007fffba118ad8 R08: 00007fffba1088e8 R09: 00007fffba108898
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffba108928 R14: 0000000000000028 R15: 0000000000008914

Allocated by task 1128:
kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
____kasan_kmalloc mm/kasan/common.c:513 [inline]
__kasan_kmalloc+0x7c/0x90 mm/kasan/common.c:522
kmalloc include/linux/slab.h:591 [inline]
kzalloc include/linux/slab.h:721 [inline]
_request_firmware_prepare drivers/base/firmware_loader/main.c:732 [inline]
_request_firmware+0x192/0x1440 drivers/base/firmware_loader/main.c:808
request_firmware_work_func+0xdd/0x230 drivers/base/firmware_loader/main.c:1079
process_one_work+0x9bf/0x1620 kernel/workqueue.c:2297
worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
kthread+0x3c2/0x4a0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 1306:
kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360
____kasan_slab_free mm/kasan/common.c:366 [inline]
____kasan_slab_free mm/kasan/common.c:328 [inline]
__kasan_slab_free+0xe0/0x110 mm/kasan/common.c:374
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:1700 [inline]
slab_free_freelist_hook mm/slub.c:1725 [inline]
slab_free mm/slub.c:3483 [inline]
kfree+0xd9/0x460 mm/slub.c:4543
release_firmware+0x1b/0x30 drivers/base/firmware_loader/main.c:1053
r871xu_dev_remove+0xcc/0x2c0 drivers/staging/rtl8712/usb_intf.c:599
usb_unbind_interface+0x1d8/0x8d0 drivers/usb/core/driver.c:458
__device_release_driver+0x5d7/0x700 drivers/base/dd.c:1205
device_release_driver_internal drivers/base/dd.c:1236 [inline]
device_release_driver+0x26/0x40 drivers/base/dd.c:1259
bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:529
device_del+0x502/0xd60 drivers/base/core.c:3583
usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1419
usb_disconnect.cold+0x27a/0x78e drivers/usb/core/hub.c:2225
hub_port_connect drivers/usb/core/hub.c:5199 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5488 [inline]
port_event drivers/usb/core/hub.c:5634 [inline]
hub_event+0x1c9c/0x4330 drivers/usb/core/hub.c:5716
process_one_work+0x9bf/0x1620 kernel/workqueue.c:2297
worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
kthread+0x3c2/0x4a0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff88810e25c9c0
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
32-byte region [ffff88810e25c9c0, ffff88810e25c9e0)
The buggy address belongs to the page:
page:ffffea0004389700 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88810e25c900 pfn:0x10e25c
flags: 0x200000000000200(slab|node=0|zone=2)
raw: 0200000000000200 ffffea000418e000 0000000c0000000c ffff888100041500
raw: ffff88810e25c900 000000008040003f 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 0x12c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY), pid 1165, ts 7264636375, free_ts 7245803911
prep_new_page mm/page_alloc.c:2424 [inline]
get_page_from_freelist+0x11d2/0x28b0 mm/page_alloc.c:4153
__alloc_pages+0x1b2/0x4e0 mm/page_alloc.c:5375
alloc_pages+0x1a7/0x300 mm/mempolicy.c:2197
alloc_slab_page mm/slub.c:1763 [inline]
allocate_slab mm/slub.c:1900 [inline]
new_slab+0x319/0x490 mm/slub.c:1963
___slab_alloc+0xa4b/0x1170 mm/slub.c:2994
__slab_alloc mm/slub.c:3081 [inline]
slab_alloc_node mm/slub.c:3172 [inline]
slab_alloc mm/slub.c:3214 [inline]
__kmalloc+0x303/0x320 mm/slub.c:4387
kmalloc include/linux/slab.h:596 [inline]
tomoyo_add_entry security/tomoyo/common.c:2031 [inline]
tomoyo_supervisor+0xce8/0xf00 security/tomoyo/common.c:2103
tomoyo_audit_path_log security/tomoyo/file.c:168 [inline]
tomoyo_path_permission security/tomoyo/file.c:587 [inline]
tomoyo_path_permission+0x270/0x3a0 security/tomoyo/file.c:573
tomoyo_check_open_permission+0x33e/0x380 security/tomoyo/file.c:777
tomoyo_file_open security/tomoyo/tomoyo.c:311 [inline]
tomoyo_file_open+0xa3/0xd0 security/tomoyo/tomoyo.c:306
security_file_open+0x45/0xb0 security/security.c:1634
do_dentry_open+0x34e/0x1110 fs/open.c:809
do_open fs/namei.c:3428 [inline]
path_openat+0x1c9a/0x2740 fs/namei.c:3561
do_filp_open+0x1aa/0x400 fs/namei.c:3588
do_sys_openat2+0x16d/0x4d0 fs/open.c:1200
do_sys_open fs/open.c:1216 [inline]
__do_sys_openat fs/open.c:1232 [inline]
__se_sys_openat fs/open.c:1227 [inline]
__x64_sys_openat+0x13f/0x1f0 fs/open.c:1227
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1338 [inline]
free_pcp_prepare+0x2b3/0x670 mm/page_alloc.c:1389
free_unref_page_prepare mm/page_alloc.c:3315 [inline]
free_unref_page+0x19/0x490 mm/page_alloc.c:3394
__vunmap+0x783/0xb70 mm/vmalloc.c:2621
free_work+0x58/0x70 mm/vmalloc.c:95
process_one_work+0x9bf/0x1620 kernel/workqueue.c:2297
worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
kthread+0x3c2/0x4a0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
ffff88810e25c880: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88810e25c900: fb fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88810e25c980: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
^
ffff88810e25ca00: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88810e25ca80: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
==================================================================


---
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[Pavel Skripkin]

On 10/19/21 18:29, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 8ef1e58783b9 usb: typec: STUSB160X should select REGMAP_I2C
> git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
> console output: https://syzkaller.appspot.com/x/log.txt?x=1106dcfb300000
> kernel config: https://syzkaller.appspot.com/x/.config?x=c27d285bdb7457e2
> dashboard link: https://syzkaller.appspot.com/bug?extid=c55162be492189fb4f51
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12725770b00000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1168c158b00000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+c55162...@syzkaller.appspotmail.com
>

Ok, this driver can't be fixed.... Let's try unregister netdev before
doing clean up stuff to not race with ->ndo_open()

#syz test:
https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing





With regards,
Pavel Skripkin

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+c55162...@syzkaller.appspotmail.com

Tested on:

commit: 8ef1e587 usb: typec: STUSB160X should select REGMAP_I2C

git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing

kernel config: https://syzkaller.appspot.com/x/.config?x=c27d285bdb7457e2
dashboard link: https://syzkaller.appspot.com/bug?extid=c55162be492189fb4f51
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=164527c8b00000

Note: testing is done by a robot and is best-effort only.