Hi all,
When implementing a syscall for FreeBSD, how do you ensure that the arguments
you have been passed are sane? I'm interested in the following syscall:
int setattr(char *file, struct stat *st, unsigned bitmap);
As far as I can see from reading similar functions, such as fhstatfs, the
correct way to do it is:
{
struct stat st;
error = copyin(SCARG(uap, st), &st, sizeof(struct stat));
if (error) { return error; }
}
Does the above code ensure that I'm safe, and I can 'trust' that there is a
struct stat 'st' that I can access normally in the code? Obviously I can't
trust the values contained in it, however can I be assured that I'm not going
to overrun or anything nasty by doing the above?
Cheers,
Grahame
--
Grahame Bowland Email: [EMAIL PROTECTED]
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The University of Western Australia Fax: +61 8 9380 1109
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