checkpatch: fix krealloc reuse test

The current krealloc test does not function correctly when the temporary
pointer return name contains the original pointer name.

Fix that by maximally matching the return pointer name and the original
pointer name and doing a separate comparison of the both names.

Link: http://lkml.kernel.org/r/e617ecb8c019a9c4c56540a1bec16c8aed43a4e4.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 4523dd6d04765b4d386641fab034afc5d0836d24..d43a446941ce544d0ebbd9a750dcbb58fb0f08aa 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -6167,7 +6167,8 @@ sub process {
 
 # check for krealloc arg reuse
                if ($perl_version_ok &&
-                   $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*\1\s*,/) {
+                   $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*($Lval)\s*,/ &&
+                   $1 eq $3) {
                        WARN("KREALLOC_ARG_REUSE",
                             "Reusing the krealloc arg is almost always a bug\n" . $herecurr);
                }