[libdvdcss-devel] [PATCH] fix uninitialized disk key usage

[Kirill Belokurov]

Hi!

Under certain conditions, the array "dvdcss->css.p_disc_key" may remain 
uninitialized till the line  (libdvdcss.c:492)

sprintf( &psz_key[1+i*2], "%.2x", dvdcss->css.p_disc_key[i] );

which will cause the "CSS keys cache folder" name to be generated using raw 
memory contents. This will lead to a bug when libdvdcss will not see the 
folder with previously cached keys and on each DVD open attempt will retry 
the brute-force keys retrieval.

The attached patch (against SVN trunk) fixes that for two different cases

libdvdcss.c: for the case when DVD is encrypted but no ioctl is available 
(which is usual for encrypted DVDs copied via dd /dev/cdrom /path/to/file )

css.c: for the case when key decryption fails, the fallback is done, but disk 
key is not zeroed

Regards, Kirill
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