tree d92bf96b009bd0b0caec44c21348812b06805909
parent b6bb324dbddd704b4b9a85971e1f7ae79abb2e1d
author David Howells <dhowells@redhat.com> 1350692369 +0100
committer Linus Torvalds <torvalds@linux-foundation.org> 1350693040 -0700

MODSIGN: Move the magic string to the end of a module and eliminate the search

Emit the magic string that indicates a module has a signature after the
signature data instead of before it.  This allows module_sig_check() to
be made simpler and faster by the elimination of the search for the
magic string.  Instead we just need to do a single memcmp().

This works because at the end of the signature data there is the
fixed-length signature information block.  This block then falls
immediately prior to the magic number.

From the contents of the information block, it is trivial to calculate
the size of the signature data and thus the size of the actual module
data.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>