[IA64] Handle count==0 in sn2_ptc_proc_write()

The fix applied in e0c6d97c65
"security hole in sn2_ptc_proc_write" didn't take into account
the case where count==0 (which results in a buffer underrun
when adding the trailing '\0').  Thanks to Andi Kleen for
pointing this out.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This commit is contained in:
Cliff Wickman 2008-06-24 10:20:06 -07:00 committed by Tony Luck
parent 2826f8c0f4
commit 8097110d17

View File

@ -512,7 +512,7 @@ static ssize_t sn2_ptc_proc_write(struct file *file, const char __user *user, si
int cpu;
char optstr[64];
if (count > sizeof(optstr))
if (count == 0 || count > sizeof(optstr))
return -EINVAL;
if (copy_from_user(optstr, user, count))
return -EFAULT;