Re: [PATCH -mm] Don't truncate /proc/PID/environ at 4096 characters

Arvin Moezzi wrote:

2007/9/19, James Pearson <[email protected]>:

+       while (count > 0) {
+               int this_len, retval;
+
+               this_len = mm->env_end - (mm->env_start + src);
+
+               if (this_len <= 0)
+                       break;
+
+               if (this_len > max_len)
+                       this_len = max_len;
+
+               retval = access_process_vm(task, (mm->env_start + src),
+                       page, this_len, 0);
+
+               if (retval <= 0) {
+                       ret = retval;
+                       break;
+               }
+
+               if (copy_to_user(buf, page, retval)) {

                                                                ^^^^
shouldn't you only copy min(count,retval) bytes? otherwise you could
write beyond the users buffer "buf", right?

AFAIK, 'retval' can never be greater than 'this_len', which can never be greater than 'max_len', which can never be greater than 'count'

James Pearson
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