[syzbot] [pvrusb2?] [usb?] KASAN: slab-use-after-free Read in pvr2_context_set_notify

syzbot
2023-07-08T12:30:59Z

Hello,

syzbot found the following issue on:

HEAD commit: 24be4d0b46bb arch/arm64/mm/fault: Fix undeclared variable ..
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=11383b04a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=f9122dc1c4589f4c
dashboard link: https://syzkaller.appspot.com/bug?extid=621409285c4156a009b3
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=14e2e43ca80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=109a3a90a80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b64cbb1118f1/disk-24be4d0b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/568048c1dd0d/vmlinux-24be4d0b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/84ac264152e7/bzImage-24be4d0b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+621409285c4156a009b3@syzkaller.appspotmail.com

==================================================================
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 ffff88810eb986d8 by task kworker/0:0/7

CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.4.0-syzkaller-11311-g24be4d0b46bb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Workqueue: usb_hub_wq hub_event

Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:364
print_report mm/kasan/report.c:475 [inline]
kasan_report+0x11d/0x130 mm/kasan/report.c:588
pvr2_context_set_notify+0x2c4/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:35
pvr_disconnect+0x80/0xf0 drivers/media/usb/pvrusb2/pvrusb2-main.c:79
usb_unbind_interface+0x1dc/0x8e0 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:569 [inline]
device_remove+0x11f/0x170 drivers/base/dd.c:561
__device_release_driver drivers/base/dd.c:1270 [inline]
device_release_driver_internal+0x443/0x610 drivers/base/dd.c:1293
bus_remove_device+0x22c/0x420 drivers/base/bus.c:574
device_del+0x399/0xa30 drivers/base/core.c:3814
usb_disable_device+0x360/0x7b0 drivers/usb/core/message.c:1420
usb_disconnect+0x2db/0x8a0 drivers/usb/core/hub.c:2253
hub_port_connect drivers/usb/core/hub.c:5261 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5566 [inline]
port_event drivers/usb/core/hub.c:5726 [inline]
hub_event+0x2073/0x4ed0 drivers/usb/core/hub.c:5808
process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597
process_scheduled_works kernel/workqueue.c:2664 [inline]
worker_thread+0x881/0x10c0 kernel/workqueue.c:2750
kthread+0x344/0x440 kernel/kthread.c:389
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>

Allocated by task 7:
kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
____kasan_kmalloc mm/kasan/common.c:374 [inline]
__kasan_kmalloc+0x7b/0x90 mm/kasan/common.c:383
kmalloc include/linux/slab.h:579 [inline]
kzalloc include/linux/slab.h:700 [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+0x30f/0x960 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x240/0xca0 drivers/base/dd.c:658
__driver_probe_device+0x1df/0x4b0 drivers/base/dd.c:798
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:828
__device_attach_driver+0x1d4/0x2e0 drivers/base/dd.c:956
bus_for_each_drv+0x149/0x1d0 drivers/base/bus.c:457
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1028
bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532
device_add+0x112d/0x1a40 drivers/base/core.c:3625
usb_set_configuration+0x1196/0x1bc0 drivers/usb/core/message.c:2211
usb_generic_driver_probe+0xcf/0x130 drivers/usb/core/generic.c:238
usb_probe_device+0xd8/0x2c0 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x240/0xca0 drivers/base/dd.c:658
__driver_probe_device+0x1df/0x4b0 drivers/base/dd.c:798
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:828
__device_attach_driver+0x1d4/0x2e0 drivers/base/dd.c:956
bus_for_each_drv+0x149/0x1d0 drivers/base/bus.c:457
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1028
bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532
device_add+0x112d/0x1a40 drivers/base/core.c:3625
usb_new_device+0xcb2/0x19d0 drivers/usb/core/hub.c:2590
hub_port_connect drivers/usb/core/hub.c:5422 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5566 [inline]
port_event drivers/usb/core/hub.c:5726 [inline]
hub_event+0x2e3d/0x4ed0 drivers/usb/core/hub.c:5808
process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597
process_scheduled_works kernel/workqueue.c:2664 [inline]
worker_thread+0x881/0x10c0 kernel/workqueue.c:2750
kthread+0x344/0x440 kernel/kthread.c:389
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Freed by task 892:
kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521
____kasan_slab_free mm/kasan/common.c:236 [inline]
____kasan_slab_free+0x144/0x1b0 mm/kasan/common.c:200
kasan_slab_free include/linux/kasan.h:162 [inline]
slab_free_hook mm/slub.c:1792 [inline]
slab_free_freelist_hook mm/slub.c:1818 [inline]
slab_free mm/slub.c:3801 [inline]
__kmem_cache_free+0xa1/0x350 mm/slub.c:3814
pvr2_context_check drivers/media/usb/pvrusb2/pvrusb2-context.c:137 [inline]
pvr2_context_thread_func+0x664/0x8e0 drivers/media/usb/pvrusb2/pvrusb2-context.c:158
kthread+0x344/0x440 kernel/kthread.c:389
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

The buggy address belongs to the object at ffff88810eb98600
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 216 bytes inside of
freed 256-byte region [ffff88810eb98600, ffff88810eb98700)

The buggy address belongs to the physical page:
page:ffffea00043ae600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10eb98
head:ffffea00043ae600 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x200000000010200(slab|head|node=0|zone=2)
page_type: 0xffffffff()
raw: 0200000000010200 ffff888100041b40 ffffea00043ae300 0000000000000003
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 7338785555, free_ts 0
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1570
prep_new_page mm/page_alloc.c:1577 [inline]
get_page_from_freelist+0x13d5/0x2cb0 mm/page_alloc.c:3221
__alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4477
alloc_page_interleave+0x1e/0x1e0 mm/mempolicy.c:2112
alloc_pages+0x233/0x270 mm/mempolicy.c:2274
alloc_slab_page mm/slub.c:1862 [inline]
allocate_slab+0x25f/0x390 mm/slub.c:2009
new_slab mm/slub.c:2062 [inline]
___slab_alloc+0xbc3/0x15d0 mm/slub.c:3215
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3314
__slab_alloc_node mm/slub.c:3367 [inline]
slab_alloc_node mm/slub.c:3460 [inline]
__kmem_cache_alloc_node+0x2c3/0x300 mm/slub.c:3509
__do_kmalloc_node mm/slab_common.c:984 [inline]
__kmalloc_node_track_caller+0x4f/0x1a0 mm/slab_common.c:1005
__do_krealloc mm/slab_common.c:1373 [inline]
krealloc+0x5e/0xf0 mm/slab_common.c:1406
add_sysfs_param+0xca/0x960 kernel/params.c:652
kernel_add_sysfs_param kernel/params.c:813 [inline]
param_sysfs_builtin kernel/params.c:852 [inline]
param_sysfs_builtin_init+0x241/0x440 kernel/params.c:986
do_one_initcall+0x105/0x630 init/main.c:1232
do_initcall_level init/main.c:1294 [inline]
do_initcalls init/main.c:1310 [inline]
do_basic_setup init/main.c:1329 [inline]
kernel_init_freeable+0x649/0xb90 init/main.c:1546
kernel_init+0x1e/0x2c0 init/main.c:1437
page_owner free stack trace missing

Memory state around the buggy address:
ffff88810eb98580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88810eb98600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88810eb98680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88810eb98700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88810eb98780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

---
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