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> > > > Secondly, they seem to use memcpy as opposed to using > > > > copy_to_user/copy_from_user which is also very > > > > dangerous. > > > > > > If they are grabbing data from user context into kernel (or vise versa) > > > that could easily cause an oops. Not to mention it is a security risk. > > > > Not to mention it simply won't work on a many platforms, no matter what... > > Hmm, I've only worked with a few platforms (i386, x86_64, ppc, mips, and > a little arm but I don't remember that much). I believe that a memcpy > could work on all these platforms (error prone of course, but if the > memory is mapped its OK). When entering a system call, the kernel still > has access to the memory locations assigned to the user. Won't work at all on platforms that have distinct address spaces for user and kernel space. E.g. on s390/s390x it wouldn't work. And yes, there are special instructions to copy data between address spaces. Heiko - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||||
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