[Linux-ima-user] buffer overflow fix

[Amadeusz S. <am...@as...>]

Hello,

I noticed that 'evmctl ima_hash file' will fail on big files and after a bit of
investigation found that code assumes that file size will fit in int
which may not always be the case.

# evmctl ima_hash /swapfile
*** buffer overflow detected ***: evmctl - terminated
evmctl: buffer overflow attack in function <unknown> - terminated
Report to http://bugs.gentoo.org/
zsh: killed     evmctl ima_hash /swapfile
# ls -lh /swapfile 
-rw-r--r--. 1 root root 3.0G Sep 13 14:07 /swapfile
# ls -l /swapfile 
-rw-r--r--. 1 root root 3221225472 Sep 13 14:07 /swapfile

After applying attached patch changing get_fdsize it works without problem.

There is also similar code in get_filesize, but I havent't changed it, it is
used later to pass filesize to malloc() in file2bin and I'm not sure if it
will work with such big files.

Amadeusz