From 60a55369aad3336e604218abf2057363f69c0722 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Wed, 4 Jun 2014 16:12:07 -0700 Subject: [PATCH] checkpatch: add warning for kmalloc/kzalloc with multiply Protect against sizeof overflows by preferring kmalloc_array/kcalloc over kmalloc/kzalloc with a sizeof multiply. Signed-off-by: Joe Perches Cc: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/checkpatch.pl | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index e7ff52a39ec9..77740252bbed 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -4378,6 +4378,30 @@ sub process { "Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr); } +# check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc + if ($^V && $^V ge 5.10.0 && + $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/) { + my $oldfunc = $3; + my $a1 = $4; + my $a2 = $10; + my $newfunc = "kmalloc_array"; + $newfunc = "kcalloc" if ($oldfunc eq "kzalloc"); + if ($a1 =~ /^sizeof\s*\S/ || $a2 =~ /^sizeof\s*\S/) { + if (WARN("ALLOC_WITH_MULTIPLY", + "Prefer $newfunc over $oldfunc with multiply\n" . $herecurr) && + $fix) { + my $r1 = $a1; + my $r2 = $a2; + if ($a1 =~ /^sizeof\s*\S/) { + $r1 = $a2; + $r2 = $a1; + } + $fixed[$linenr - 1] =~ s/\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/$1 . ' = ' . "$newfunc(" . trim($r1) . ', ' . trim($r2)/e; + + } + } + } + # 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*,/) { -- 2.20.1