CVE-2024-26875

In the Linux kernel, the following vulnerability has been resolved: media:
pvrusb2: fix uaf in pvr2_context_set_notify [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.