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    [media] siano: firmware buffer is too small · 21cf734c
    Mauro Carvalho Chehab 提交于
    As pointed by KASAN:
    
    	BUG: KASAN: slab-out-of-bounds in memcpy+0x1d/0x40 at addr ffff880000038d8c
    	Read of size 128 by task systemd-udevd/2536
    	page:ffffea0000000800 count:1 mapcount:0 mapping:          (null) index:0x0 compound_mapcount: 0
    	flags: 0xffff8000004000(head)
    	page dumped because: kasan: bad access detected
    	CPU: 1 PID: 2536 Comm: systemd-udevd Not tainted 4.5.0-rc3+ #47
    	Hardware name:                  /NUC5i7RYB, BIOS RYBDWi35.86A.0350.2015.0812.1722 08/12/2015
    	  ffff880000038d8c ffff8803b0f1f1e8 ffffffff81933901 0000000000000080
    	  ffff8803b0f1f280 ffff8803b0f1f270 ffffffff815602c5 ffffffff8284cf93
    	  ffffffff822ddc00 0000000000000282 0000000000000001 ffff88009c7c6000
    	Call Trace:
    	  [<ffffffff81933901>] dump_stack+0x85/0xc4
    	  [<ffffffff815602c5>] kasan_report_error+0x525/0x550
    	  [<ffffffff815606e9>] kasan_report+0x39/0x40
    	  [<ffffffff8155f84d>] memcpy+0x1d/0x40
    	  [<ffffffffa120cb90>] smscore_set_device_mode+0xee0/0x2560 [smsmdtv]
    
    Such error happens at the memcpy code below:
    
    0x4bc0 is in smscore_set_device_mode (drivers/media/common/siano/smscoreapi.c:975).
    970					      sizeof(u32) + payload_size));
    971
    972			data_msg->mem_addr = mem_address;
    973			memcpy(data_msg->payload, payload, payload_size);
    974
    975			rc = smscore_sendrequest_and_wait(coredev, data_msg,
    976					data_msg->x_msg_header.msg_length,
    977					&coredev->data_download_done);
    978
    979			payload += payload_size;
    
    The problem is that the Siano driver uses a header to store the firmware,
    with requires a few more bytes than allocated.
    
    Tested with:
    	PCTV 77e (2013:0257)
    	Hauppauge WinTV MiniStick (2040:5510)
    Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>
    21cf734c
smscoreapi.c 79.5 KB