CVE request: kernel: parisc: isa-eeprom missing lower bound check

[Eugene Teo <eugeneteo () kernel sg>]

loff_t is a signed type. If userspace passes a negative ppos, the
"count" range check is weakened. If ppos is negative, the readb() later
in the function will poke in random memory. Only affects if you are
using a PA-RISC kernel with CONFIG_EISA set.

Upstream commit:
http://git.kernel.org/linus/6b4dbcd86a9d464057fcc7abe4d0574093071fcc

Reference:
http://patchwork.kernel.org/patch/36418/

Thanks, Eugene