[syzbot] [pvrusb2?] KASAN: slab-use-after-free Read in pvr2_context_set_notify (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f1a27f081c1f usb: typec: qcom-pmic-typec: allow different ..
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=159f19fde80000
kernel config: https://syzkaller.appspot.com/x/.config?x=70204d1d16341bf4
dashboard link: https://syzkaller.appspot.com/bug?extid=ce750e124675d4599449
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5c37a861daee/disk-f1a27f08.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/09f1af46fd09/vmlinux-f1a27f08.xz
kernel image: https://storage.googleapis.com/syzbot-assets/82eb085e0be1/bzImage-f1a27f08.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ce750e...@syzkaller.appspotmail.com

pvrusb2: Device being rendered inoperable
==================================================================
BUG: KASAN: slab-use-after-free in pvr2_context_set_notify+0x2c4/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:35
Read of size 4 at addr ffff888111b8fed8 by task kworker/0:6/8544

CPU: 0 PID: 8544 Comm: kworker/0:6 Not tainted 6.8.0-rc1-syzkaller-00046-gf1a27f081c1f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc4/0x620 mm/kasan/report.c:488
kasan_report+0xda/0x110 mm/kasan/report.c:601
pvr2_context_set_notify+0x2c4/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:35
pvr2_context_notify drivers/media/usb/pvrusb2/pvrusb2-context.c:95 [inline]
pvr2_context_disconnect+0x94/0xb0 drivers/media/usb/pvrusb2/pvrusb2-context.c:272
pvr_disconnect+0x80/0xf0 drivers/media/usb/pvrusb2/pvrusb2-main.c:79
usb_unbind_interface+0x1e5/0x960 drivers/usb/core/driver.c:461
device_remove drivers/base/dd.c:569 [inline]
device_remove+0x11f/0x170 drivers/base/dd.c:561
__device_release_driver drivers/base/dd.c:1272 [inline]
device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1295
bus_remove_device+0x22c/0x420 drivers/base/bus.c:574
device_del+0x39a/0xa50 drivers/base/core.c:3814
usb_disable_device+0x36c/0x7f0 drivers/usb/core/message.c:1416
usb_disconnect+0x2e1/0x910 drivers/usb/core/hub.c:2286
hub_port_connect drivers/usb/core/hub.c:5334 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5634 [inline]
port_event drivers/usb/core/hub.c:5794 [inline]
hub_event+0x1be0/0x4f40 drivers/usb/core/hub.c:5876
process_one_work+0x884/0x15c0 kernel/workqueue.c:2633
process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787
kthread+0x33c/0x440 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
</TASK>

Allocated by task 8544:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:372 [inline]
__kasan_kmalloc+0x87/0x90 mm/kasan/common.c:389
kmalloc include/linux/slab.h:590 [inline]
kzalloc include/linux/slab.h:711 [inline]
pvr2_context_create+0x53/0x2a0 drivers/media/usb/pvrusb2/pvrusb2-context.c:207
pvr_probe+0x25/0xe0 drivers/media/usb/pvrusb2/pvrusb2-main.c:54
usb_probe_interface+0x307/0x9c0 drivers/usb/core/driver.c:399
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x234/0xc90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x4b0 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:830
__device_attach_driver+0x1d4/0x300 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1d0 drivers/base/bus.c:457
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532
device_add+0x117e/0x1aa0 drivers/base/core.c:3625
usb_set_configuration+0x10cb/0x1c40 drivers/usb/core/message.c:2207
usb_generic_driver_probe+0xad/0x110 drivers/usb/core/generic.c:254
usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:294
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x234/0xc90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x4b0 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:830
__device_attach_driver+0x1d4/0x300 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1d0 drivers/base/bus.c:457
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532
device_add+0x117e/0x1aa0 drivers/base/core.c:3625
usb_new_device+0xd80/0x19f0 drivers/usb/core/hub.c:2625
hub_port_connect drivers/usb/core/hub.c:5494 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5634 [inline]
port_event drivers/usb/core/hub.c:5794 [inline]
hub_event+0x2e62/0x4f40 drivers/usb/core/hub.c:5876
process_one_work+0x884/0x15c0 kernel/workqueue.c:2633
process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787
kthread+0x33c/0x440 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Freed by task 897:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640
poison_slab_object mm/kasan/common.c:241 [inline]
__kasan_slab_free+0x106/0x1b0 mm/kasan/common.c:257
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2121 [inline]
slab_free mm/slub.c:4299 [inline]
kfree+0x105/0x330 mm/slub.c:4409
pvr2_context_check drivers/media/usb/pvrusb2/pvrusb2-context.c:137 [inline]
pvr2_context_thread_func+0x69d/0x960 drivers/media/usb/pvrusb2/pvrusb2-context.c:158
kthread+0x33c/0x440 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

The buggy address belongs to the object at ffff888111b8fe00
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 216 bytes inside of
freed 256-byte region [ffff888111b8fe00, ffff888111b8ff00)

The buggy address belongs to the physical page:
page:ffffea000446e380 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x111b8e
head:ffffea000446e380 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x200000000000840(slab|head|node=0|zone=2)
page_type: 0xffffffff()
raw: 0200000000000840 ffff888100041b40 ffffea0004698e80 dead000000000003
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6208, tgid 6208 (dhcpcd-run-hook), ts 253184444708, free_ts 252376724208
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1533
prep_new_page mm/page_alloc.c:1540 [inline]
get_page_from_freelist+0x139a/0x3460 mm/page_alloc.c:3311
__alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4567
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page mm/slub.c:2190 [inline]
allocate_slab+0xa3/0x360 mm/slub.c:2354
new_slab mm/slub.c:2407 [inline]
___slab_alloc+0x4d2/0x1950 mm/slub.c:3540
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3625
__slab_alloc_node mm/slub.c:3678 [inline]
slab_alloc_node mm/slub.c:3850 [inline]
__do_kmalloc_node mm/slub.c:3980 [inline]
__kmalloc_node+0x177/0x4b0 mm/slub.c:3988
kmalloc_array_node include/linux/slab.h:688 [inline]
kcalloc_node include/linux/slab.h:693 [inline]
memcg_alloc_slab_cgroups+0xa9/0x170 mm/memcontrol.c:2988
account_slab mm/slub.c:2317 [inline]
allocate_slab+0x2b5/0x360 mm/slub.c:2372
new_slab mm/slub.c:2407 [inline]
___slab_alloc+0x4d2/0x1950 mm/slub.c:3540
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3625
__slab_alloc_node mm/slub.c:3678 [inline]
slab_alloc_node mm/slub.c:3850 [inline]
kmem_cache_alloc+0x326/0x370 mm/slub.c:3867
anon_vma_chain_alloc mm/rmap.c:142 [inline]
anon_vma_fork+0x1fc/0x610 mm/rmap.c:365
dup_mmap kernel/fork.c:712 [inline]
dup_mm kernel/fork.c:1685 [inline]
copy_mm kernel/fork.c:1734 [inline]
copy_process+0x9306/0x9920 kernel/fork.c:2496
kernel_clone+0xfc/0x850 kernel/fork.c:2901
__do_sys_clone+0xba/0x100 kernel/fork.c:3044
page last free pid 4799 tgid 4799 stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1140 [inline]
free_unref_page_prepare+0x503/0xae0 mm/page_alloc.c:2346
free_unref_page+0x33/0x2c0 mm/page_alloc.c:2486
__put_partials+0x149/0x160 mm/slub.c:2922
qlink_free mm/kasan/quarantine.c:160 [inline]
qlist_free_all+0x58/0x150 mm/kasan/quarantine.c:176
kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:283
__kasan_slab_alloc+0x4a/0x70 mm/kasan/common.c:324
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook mm/slub.c:3813 [inline]
slab_alloc_node mm/slub.c:3860 [inline]
kmalloc_trace+0x13a/0x390 mm/slub.c:4007
kmalloc include/linux/slab.h:590 [inline]
usb_control_msg+0xbd/0x4a0 drivers/usb/core/message.c:144
get_bMaxPacketSize0+0xc3/0x280 drivers/usb/core/hub.c:4779
hub_port_init+0x6a8/0x3a50 drivers/usb/core/hub.c:4975
hub_port_connect drivers/usb/core/hub.c:5423 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5634 [inline]
port_event drivers/usb/core/hub.c:5794 [inline]
hub_event+0x2c20/0x4f40 drivers/usb/core/hub.c:5876
process_one_work+0x884/0x15c0 kernel/workqueue.c:2633
process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787
kthread+0x33c/0x440 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Memory state around the buggy address:
ffff888111b8fd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888111b8fe00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888111b8fe80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888111b8ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888111b8ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================


---
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If you want to undo deduplication, reply with:
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: f1a27f081c1f usb: typec: qcom-pmic-typec: allow different ..
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=14800bdfe80000
kernel config: https://syzkaller.appspot.com/x/.config?x=986ce9258c6856ff

dashboard link: https://syzkaller.appspot.com/bug?extid=ce750e124675d4599449
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17c7cad3e80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1429ed40180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c77efcf770e8/disk-f1a27f08.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a827d6ba40bf/vmlinux-f1a27f08.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9d21d228bf73/bzImage-f1a27f08.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ce750e...@syzkaller.appspotmail.com

pvrusb2: Device being rendered inoperable
==================================================================
BUG: KASAN: slab-use-after-free in pvr2_context_set_notify+0x2c4/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:35

Read of size 4 at addr ffff888112202ad8 by task kworker/0:1/9

CPU: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.8.0-rc1-syzkaller-00046-gf1a27f081c1f #0

process_one_work+0x886/0x15d0 kernel/workqueue.c:2633

process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787

kthread+0x2c6/0x3a0 kernel/kthread.c:388

ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
</TASK>

Allocated by task 9:

process_one_work+0x886/0x15d0 kernel/workqueue.c:2633

process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787

kthread+0x2c6/0x3a0 kernel/kthread.c:388

ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Freed by task 901:

kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640
poison_slab_object mm/kasan/common.c:241 [inline]
__kasan_slab_free+0x106/0x1b0 mm/kasan/common.c:257
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2121 [inline]
slab_free mm/slub.c:4299 [inline]

kfree+0x105/0x340 mm/slub.c:4409

pvr2_context_check drivers/media/usb/pvrusb2/pvrusb2-context.c:137 [inline]
pvr2_context_thread_func+0x69d/0x960 drivers/media/usb/pvrusb2/pvrusb2-context.c:158

kthread+0x2c6/0x3a0 kernel/kthread.c:388

ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

The buggy address belongs to the object at ffff888112202a00

which belongs to the cache kmalloc-256 of size 256
The buggy address is located 216 bytes inside of

freed 256-byte region [ffff888112202a00, ffff888112202b00)

The buggy address belongs to the physical page:

page:ffffea0004488080 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x112202
head:ffffea0004488080 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0

anon flags: 0x200000000000840(slab|head|node=0|zone=2)
page_type: 0xffffffff()

raw: 0200000000000840 ffff888100041b40 ffffea0004498080 0000000000000005
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000

page dumped because: kasan: bad access detected
page_owner tracks the page as allocated

page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 7680321640, free_ts 0
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1533
prep_new_page mm/page_alloc.c:1540 [inline]
get_page_from_freelist+0x139c/0x3470 mm/page_alloc.c:3311
__alloc_pages+0x228/0x2250 mm/page_alloc.c:4567

__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page mm/slub.c:2190 [inline]

allocate_slab mm/slub.c:2354 [inline]
new_slab+0xcc/0x3a0 mm/slub.c:2407
___slab_alloc+0x4b0/0x1860 mm/slub.c:3540

__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3625
__slab_alloc_node mm/slub.c:3678 [inline]
slab_alloc_node mm/slub.c:3850 [inline]
__do_kmalloc_node mm/slub.c:3980 [inline]

__kmalloc_node_track_caller+0x171/0x420 mm/slub.c:4001
__do_krealloc mm/slab_common.c:1187 [inline]
krealloc+0x5d/0xf0 mm/slab_common.c:1220
add_sysfs_param+0xca/0x960 kernel/params.c:654
kernel_add_sysfs_param kernel/params.c:817 [inline]
param_sysfs_builtin kernel/params.c:856 [inline]
param_sysfs_builtin_init+0x2ca/0x450 kernel/params.c:990
do_one_initcall+0x11c/0x650 init/main.c:1236
do_initcall_level init/main.c:1298 [inline]
do_initcalls init/main.c:1314 [inline]
do_basic_setup init/main.c:1333 [inline]
kernel_init_freeable+0x682/0xc10 init/main.c:1551
kernel_init+0x1c/0x2a0 init/main.c:1441

ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

page_owner free stack trace missing

Memory state around the buggy address:

ffff888112202980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888112202a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888112202a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888112202b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888112202b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

[Hillf Danton]

On Wed, 31 Jan 2024 02:22:39 -0800

> HEAD commit: f1a27f081c1f usb: typec: qcom-pmic-typec: allow different ..
> git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1429ed40180000

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

--- x/drivers/media/usb/pvrusb2/pvrusb2-context.c
+++ y/drivers/media/usb/pvrusb2/pvrusb2-context.c
@@ -267,9 +267,9 @@ static void pvr2_context_exit(struct pvr
void pvr2_context_disconnect(struct pvr2_context *mp)
{
pvr2_hdw_disconnect(mp->hdw);
- mp->disconnect_flag = !0;
if (!pvr2_context_shutok())
pvr2_context_notify(mp);
+ pvr2_context_destroy(mp);
}


--

[Edward Adam Davis]

please test uaf in pvr2_context_set_notify

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

diff --git a/drivers/media/usb/pvrusb2/pvrusb2-context.c b/drivers/media/usb/pvrusb2/pvrusb2-context.c
index 1764674de98b..e93bca93ce4c 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-context.c
+++ b/drivers/media/usb/pvrusb2/pvrusb2-context.c
@@ -267,9 +267,9 @@ static void pvr2_context_exit(struct pvr2_context *mp)

void pvr2_context_disconnect(struct pvr2_context *mp)
{
pvr2_hdw_disconnect(mp->hdw);
- mp->disconnect_flag = !0;
if (!pvr2_context_shutok())
pvr2_context_notify(mp);

+ mp->disconnect_flag = !0;
}

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in pvr2_context_set_notify

pvrusb2: You might need to power cycle the pvrusb2 device in order to recover.
==================================================================
BUG: KASAN: slab-use-after-free in pvr2_context_set_notify+0x2ba/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:48
Read of size 4 at addr ffff88810fb02ed8 by task pvrusb2-context/902

CPU: 0 PID: 902 Comm: pvrusb2-context Not tainted 6.8.0-rc4-syzkaller-00180-g4f5e5092fdbf-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024

Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc4/0x620 mm/kasan/report.c:488
kasan_report+0xda/0x110 mm/kasan/report.c:601

pvr2_context_set_notify+0x2ba/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:48
pvr2_context_thread_func+0x10d/0x960 drivers/media/usb/pvrusb2/pvrusb2-context.c:157

kthread+0x2c6/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
</TASK>

Allocated by task 724:

kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:372 [inline]
__kasan_kmalloc+0x87/0x90 mm/kasan/common.c:389
kmalloc include/linux/slab.h:590 [inline]
kzalloc include/linux/slab.h:711 [inline]
pvr2_context_create+0x53/0x2a0 drivers/media/usb/pvrusb2/pvrusb2-context.c:207
pvr_probe+0x25/0xe0 drivers/media/usb/pvrusb2/pvrusb2-main.c:54

usb_probe_interface+0x307/0x930 drivers/usb/core/driver.c:399

call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x234/0xc90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x4b0 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:830
__device_attach_driver+0x1d4/0x300 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1d0 drivers/base/bus.c:457
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532
device_add+0x117e/0x1aa0 drivers/base/core.c:3625
usb_set_configuration+0x10cb/0x1c40 drivers/usb/core/message.c:2207
usb_generic_driver_probe+0xad/0x110 drivers/usb/core/generic.c:254

usb_probe_device+0xec/0x350 drivers/usb/core/driver.c:294

call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x234/0xc90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x4b0 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:830
__device_attach_driver+0x1d4/0x300 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1d0 drivers/base/bus.c:457
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532
device_add+0x117e/0x1aa0 drivers/base/core.c:3625

usb_new_device+0xd90/0x1a10 drivers/usb/core/hub.c:2614
hub_port_connect drivers/usb/core/hub.c:5483 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5623 [inline]
port_event drivers/usb/core/hub.c:5783 [inline]
hub_event+0x2e62/0x4f40 drivers/usb/core/hub.c:5865

process_one_work+0x886/0x15d0 kernel/workqueue.c:2633
process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787
kthread+0x2c6/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Freed by task 724:

kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640
poison_slab_object mm/kasan/common.c:241 [inline]
__kasan_slab_free+0x106/0x1b0 mm/kasan/common.c:257
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2121 [inline]
slab_free mm/slub.c:4299 [inline]
kfree+0x105/0x340 mm/slub.c:4409

pvr_disconnect+0x80/0xf0 drivers/media/usb/pvrusb2/pvrusb2-main.c:79
usb_unbind_interface+0x1dd/0x8d0 drivers/usb/core/driver.c:461

device_remove drivers/base/dd.c:569 [inline]
device_remove+0x11f/0x170 drivers/base/dd.c:561
__device_release_driver drivers/base/dd.c:1272 [inline]
device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1295
bus_remove_device+0x22c/0x420 drivers/base/bus.c:574
device_del+0x39a/0xa50 drivers/base/core.c:3814
usb_disable_device+0x36c/0x7f0 drivers/usb/core/message.c:1416

usb_disconnect+0x2e1/0x910 drivers/usb/core/hub.c:2267
hub_port_connect drivers/usb/core/hub.c:5323 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5623 [inline]
port_event drivers/usb/core/hub.c:5783 [inline]
hub_event+0x1be0/0x4f40 drivers/usb/core/hub.c:5865

process_one_work+0x886/0x15d0 kernel/workqueue.c:2633
process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787
kthread+0x2c6/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

The buggy address belongs to the object at ffff88810fb02e00

which belongs to the cache kmalloc-256 of size 256
The buggy address is located 216 bytes inside of

freed 256-byte region [ffff88810fb02e00, ffff88810fb02f00)

The buggy address belongs to the physical page:

page:ffffea00043ec080 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10fb02
head:ffffea00043ec080 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0

flags: 0x200000000000840(slab|head|node=0|zone=2)
page_type: 0xffffffff()

raw: 0200000000000840 ffff888100041b40 ffffea00041ef600 0000000000000002
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000

page dumped because: kasan: bad access detected
page_owner tracks the page as allocated

page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5358, tgid 5358 (kworker/1:4), ts 131458586273, free_ts 131438325014

set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1533
prep_new_page mm/page_alloc.c:1540 [inline]
get_page_from_freelist+0x139c/0x3470 mm/page_alloc.c:3311
__alloc_pages+0x228/0x2250 mm/page_alloc.c:4567
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page mm/slub.c:2190 [inline]
allocate_slab mm/slub.c:2354 [inline]
new_slab+0xcc/0x3a0 mm/slub.c:2407
___slab_alloc+0x4b0/0x1860 mm/slub.c:3540
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3625
__slab_alloc_node mm/slub.c:3678 [inline]
slab_alloc_node mm/slub.c:3850 [inline]

kmalloc_trace+0x2ce/0x300 mm/slub.c:4007

kmalloc include/linux/slab.h:590 [inline]
kzalloc include/linux/slab.h:711 [inline]
pvr2_context_create+0x53/0x2a0 drivers/media/usb/pvrusb2/pvrusb2-context.c:207
pvr_probe+0x25/0xe0 drivers/media/usb/pvrusb2/pvrusb2-main.c:54

usb_probe_interface+0x307/0x930 drivers/usb/core/driver.c:399

call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x234/0xc90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x4b0 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:830
__device_attach_driver+0x1d4/0x300 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1d0 drivers/base/bus.c:457
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030

page last free pid 5341 tgid 5341 stack trace:

reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1140 [inline]

free_unref_page_prepare+0x504/0xae0 mm/page_alloc.c:2346
free_unref_page+0x33/0x2d0 mm/page_alloc.c:2486

qlink_free mm/kasan/quarantine.c:160 [inline]
qlist_free_all+0x58/0x150 mm/kasan/quarantine.c:176
kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:283
__kasan_slab_alloc+0x4a/0x70 mm/kasan/common.c:324
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook mm/slub.c:3813 [inline]
slab_alloc_node mm/slub.c:3860 [inline]

kmem_cache_alloc+0x131/0x2e0 mm/slub.c:3867
getname_flags.part.0+0x50/0x4e0 fs/namei.c:140
getname_flags+0x9c/0xf0 include/linux/audit.h:322
vfs_fstatat+0x9a/0x140 fs/stat.c:303
__do_sys_newfstatat+0x98/0x110 fs/stat.c:468
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

Memory state around the buggy address:

ffff88810fb02d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88810fb02e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88810fb02e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88810fb02f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88810fb02f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================


Tested on:

commit: 4f5e5092 Merge tag 'net-6.8-rc5' of git://git.kernel.o..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=17133c1c180000
kernel config: https://syzkaller.appspot.com/x/.config?x=4f5e432f25b85a97

dashboard link: https://syzkaller.appspot.com/bug?extid=ce750e124675d4599449
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=12c58494180000

[syzbot]

Hello,

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

Reported-and-tested-by: syzbot+ce750e...@syzkaller.appspotmail.com

Tested on:

commit: 88bae831 usb: typec: ucsi: Add qcm6490-pmic-glink as n..

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=16675a78180000
kernel config: https://syzkaller.appspot.com/x/.config?x=28a3704ea90ef255

dashboard link: https://syzkaller.appspot.com/bug?extid=ce750e124675d4599449
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=15e33c1c180000

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

[Edward Adam Davis]

[Syzbot reported]

BUG: KASAN: slab-use-after-free in pvr2_context_set_notify+0x2c4/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:35

Read of size 4 at addr ffff888113aeb0d8 by task kworker/1:1/26

CPU: 1 PID: 26 Comm: kworker/1:1 Not tainted 6.8.0-rc1-syzkaller-00046-gf1a27f081c1f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024

Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc4/0x620 mm/kasan/report.c:488
kasan_report+0xda/0x110 mm/kasan/report.c:601
pvr2_context_set_notify+0x2c4/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:35
pvr2_context_notify drivers/media/usb/pvrusb2/pvrusb2-context.c:95 [inline]
pvr2_context_disconnect+0x94/0xb0 drivers/media/usb/pvrusb2/pvrusb2-context.c:272

Freed by task 906:

kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640
poison_slab_object mm/kasan/common.c:241 [inline]
__kasan_slab_free+0x106/0x1b0 mm/kasan/common.c:257
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2121 [inline]
slab_free mm/slub.c:4299 [inline]
kfree+0x105/0x340 mm/slub.c:4409
pvr2_context_check drivers/media/usb/pvrusb2/pvrusb2-context.c:137 [inline]
pvr2_context_thread_func+0x69d/0x960 drivers/media/usb/pvrusb2/pvrusb2-context.c:158

[Analyze]
Task A set disconnect_flag = !0, which resulted in Task B's condition being met
and releasing mp, leading to this issue.

[Fix]
Place the disconnect_flag assignment operation after all code in pvr2_context_disconnect()
to avoid this issue.

Reported-and-tested-by: syzbot+ce750e...@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <ead...@qq.com>
---
drivers/media/usb/pvrusb2/pvrusb2-context.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/usb/pvrusb2/pvrusb2-context.c b/drivers/media/usb/pvrusb2/pvrusb2-context.c
index 1764674de98b..e93bca93ce4c 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-context.c
+++ b/drivers/media/usb/pvrusb2/pvrusb2-context.c
@@ -267,9 +267,9 @@ static void pvr2_context_exit(struct pvr2_context *mp)
void pvr2_context_disconnect(struct pvr2_context *mp)
{
pvr2_hdw_disconnect(mp->hdw);
- mp->disconnect_flag = !0;
if (!pvr2_context_shutok())
pvr2_context_notify(mp);
+ mp->disconnect_flag = !0;
}

--
2.43.0

[Greg KH]

What commit id does this fix?

And should it be cc: stable as well?

thanks,

greg k-h

[Edward Adam Davis]

e5be15c63804 ("V4L/DVB (7711): pvrusb2: Fix race on module unload")

>
> And should it be cc: stable as well?

I checked the stable git tree and it introduced e5be15c63804. I think we need to
cc stable.

thanks,
edward

[Edward Adam Davis]

Fixes: e5be15c63804 ("V4L/DVB (7711): pvrusb2: Fix race on module unload")
cc: sta...@vger.kernel.org

Signed-off-by: Edward Adam Davis <ead...@qq.com>