checkpatch: add check for reuse of krealloc arg

On Thu, 2013-03-14 at 13:30 +0000, David Woodhouse wrote: > If krealloc() returns NULL, it *doesn't* free the original. So any code > of the form 'foo = krealloc(foo, …);' is almost certainly a bug. So add a check for it to checkpatch. Signed-off-by: Joe Perches <[email protected]> Tested-by: Guenter Roeck <[email protected]> Acked-by: Guenter Roeck <[email protected]> Cc: David Woodhouse <[email protected]> Cc: Andy Whitcroft <[email protected]> Cc: Jean Delvare <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
klaby · Apr 30, 2013 · 972fdea · 972fdea
1 parent 2e0fb40
commit 972fdea
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
@@ -3477,6 +3477,13 @@ sub process {
 			     "unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr);
 		}
 
+# check for krealloc arg reuse
+		if ($^V && $^V ge 5.10.0 &&
+		    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*\1\s*,/) {
+			WARN("KREALLOC_ARG_REUSE",
+			     "Reusing the krealloc arg is almost always a bug\n" . $herecurr);
+		}
+
 # check for alloc argument mismatch
 		if ($line =~ /\b(kcalloc|kmalloc_array)\s*\(\s*sizeof\b/) {
 			WARN("ALLOC_ARRAY_ARGS",