[IA64] SN2: security hole in sn2_ptc_proc_write

Security hole in sn2_ptc_proc_write

It is possible to overrun a buffer with a write to this /proc file.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

diff --git a/arch/ia64/sn/kernel/sn2/sn2_smp.c b/arch/ia64/sn/kernel/sn2/sn2_smp.c
index 49d3120415eb740154a5469be144e51598775d04..6dd886c5d860a29dd71b7c91a168728ff97b4611 100644 (file)
--- a/arch/ia64/sn/kernel/sn2/sn2_smp.c
+++ b/arch/ia64/sn/kernel/sn2/sn2_smp.c
@@ -512,6 +512,8 @@ static ssize_t sn2_ptc_proc_write(struct file *file, const char __user *user, si
        int cpu;
        char optstr[64];
 
+       if (count > sizeof(optstr))
+               return -EINVAL;
        if (copy_from_user(optstr, user, count))
                return -EFAULT;
        optstr[count - 1] = '\0';