[ Upstream commit ab599eb118 ]
I got a use-after-free report:
dvbdev: dvb_register_device: failed to create device dvb1.dvr0 (-12)
...
==================================================================
BUG: KASAN: use-after-free in dvb_dmxdev_release+0xce/0x2f0
...
Call Trace:
dump_stack_lvl+0x6c/0x8b
print_address_description.constprop.0+0x48/0x70
kasan_report.cold+0x82/0xdb
__asan_load4+0x6b/0x90
dvb_dmxdev_release+0xce/0x2f0
...
Allocated by task 7666:
kasan_save_stack+0x23/0x50
__kasan_kmalloc+0x83/0xa0
kmem_cache_alloc_trace+0x22e/0x470
dvb_register_device+0x12f/0x980
dvb_dmxdev_init+0x1f3/0x230
...
Freed by task 7666:
kasan_save_stack+0x23/0x50
kasan_set_track+0x20/0x30
kasan_set_free_info+0x24/0x40
__kasan_slab_free+0xf2/0x130
kfree+0xd1/0x5c0
dvb_register_device.cold+0x1ac/0x1fa
dvb_dmxdev_init+0x1f3/0x230
...
When dvb_register_device() in dvb_dmxdev_init() fails, dvb_dmxdev_init()
does not return a failure, and the memory pointed to by dvbdev or
dvr_dvbdev is invalid at this point. If they are used subsequently, it
will result in UFA or null-ptr-deref.
If dvb_register_device() in dvb_dmxdev_init() fails, fix the bug by making
dvb_dmxdev_init() return an error as well.
Link: https://lore.kernel.org/linux-media/20211015085741.1203283-1-wanghai38@huawei.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
4d6a558bde