1 files changed, 2 insertions, 0 deletions

diff --git a/arch/ia64/sn/kernel/sn2/sn2_smp.c b/arch/ia64/sn/kernel/sn2/sn2_smp.c
index 49d3120415e..e585f9a2afb 100644
--- 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 == 0 || count > sizeof(optstr))
+                return -EINVAL;
         if (copy_from_user(optstr, user, count))
                 return -EFAULT;
         optstr[count - 1] = '\0';