commit 3ace678fd1b246b75e01eeac0554de35656136a4
author Andrey Ryabinin <a.ryabinin@samsung.com> Mon Jan 27 17:06:58 2014 -0800
committer Linus Torvalds <torvalds@linux-foundation.org> Mon Jan 27 21:02:39 2014 -0800
tree 81db6091116b988123782988a37f8eadb4b4c55c
parent d9e133e6f05fbb39e2ecf7bc1edca299729a8595

dynamic_debug: fix ddebug_parse_query()

This fixes following scenario:

  $ echo 'file dynamic_debug.c line 1-123 +p' > /sys/kernel/debug/dynamic_debug/control
  -bash: echo: write error: Invalid argument
  $ dmesg | grep dynamic_debug
  dynamic_debug:ddebug_parse_query: last-line:123 < 1st-line:1
  dynamic_debug:ddebug_parse_query: query parse failed

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Jason Baron <jbaron@akamai.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/dynamic_debug.c

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index f959c39..e488d9a 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -352,8 +352,10 @@
 				return -EINVAL;
 			if (last) {
 				/* range <first>-<last> */
-				if (parse_lineno(last, &query->last_lineno)
-				    < query->first_lineno) {
+				if (parse_lineno(last, &query->last_lineno) < 0)
+					return -EINVAL;
+
+				if (query->last_lineno < query->first_lineno) {
 					pr_err("last-line:%d < 1st-line:%d\n",
 						query->last_lineno,
 						query->first_lineno);