checkpatch: add warning for kmalloc/kzalloc with multiply

Protect against sizeof overflows by preferring kmalloc_array/kcalloc over
kmalloc/kzalloc with a sizeof multiply.

Change-Id: I30b4a314eb21c672d7096af1ef565a5b54d12777
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 60a55369aad3336e604218abf2057363f69c0722
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
This commit is contained in:
Joe Perches 2014-06-04 16:12:07 -07:00 committed by Stepan Moskovchenko
parent 32c5d34caf
commit a3f8de30e9
1 changed files with 24 additions and 0 deletions

View File

@ -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*,/) {