treewide: kmalloc() -> kmalloc_array()

The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>

7 files changed, 12 insertions, 10 deletions

diff --git a/lib/argv_split.c b/lib/argv_split.c
index 5c35752..1a19a0a 100644
--- a/lib/argv_split.c
+++ b/lib/argv_split.c
@@ -69,7 +69,7 @@ char **argv_split(gfp_t gfp, const char *str, int *argcp)
 		return NULL;
 
 	argc = count_argc(argv_str);
-	argv = kmalloc(sizeof(*argv) * (argc + 2), gfp);
+	argv = kmalloc_array(argc + 2, sizeof(*argv), gfp);
 	if (!argv) {
 		kfree(argv_str);
 		return NULL;
diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c
index 835242e..75509a1 100644
--- a/lib/interval_tree_test.c
+++ b/lib/interval_tree_test.c
@@ -64,11 +64,12 @@ static int interval_tree_test_init(void)
 	unsigned long results;
 	cycles_t time1, time2, time;
 
-	nodes = kmalloc(nnodes * sizeof(struct interval_tree_node), GFP_KERNEL);
+	nodes = kmalloc_array(nnodes, sizeof(struct interval_tree_node),
+			      GFP_KERNEL);
 	if (!nodes)
 		return -ENOMEM;
 
-	queries = kmalloc(nsearches * sizeof(int), GFP_KERNEL);
+	queries = kmalloc_array(nsearches, sizeof(int), GFP_KERNEL);
 	if (!queries) {
 		kfree(nodes);
 		return -ENOMEM;
diff --git a/lib/kfifo.c b/lib/kfifo.c
index b0f757b..015656a 100644
--- a/lib/kfifo.c
+++ b/lib/kfifo.c
@@ -54,7 +54,7 @@ int __kfifo_alloc(struct __kfifo *fifo, unsigned int size,
 		return -EINVAL;
 	}
 
-	fifo->data = kmalloc(size * esize, gfp_mask);
+	fifo->data = kmalloc_array(esize, size, gfp_mask);
 
 	if (!fifo->data) {
 		fifo->mask = 0;
diff --git a/lib/mpi/mpiutil.c b/lib/mpi/mpiutil.c
index 314f4df..2dbfc4c 100644
--- a/lib/mpi/mpiutil.c
+++ b/lib/mpi/mpiutil.c
@@ -91,7 +91,7 @@ int mpi_resize(MPI a, unsigned nlimbs)
 		return 0;	/* no need to do it */
 
 	if (a->d) {
-		p = kmalloc(nlimbs * sizeof(mpi_limb_t), GFP_KERNEL);
+		p = kmalloc_array(nlimbs, sizeof(mpi_limb_t), GFP_KERNEL);
 		if (!p)
 			return -ENOMEM;
 		memcpy(p, a->d, a->alloced * sizeof(mpi_limb_t));
diff --git a/lib/rbtree_test.c b/lib/rbtree_test.c
index 7d36c1e..b7055b2 100644
--- a/lib/rbtree_test.c
+++ b/lib/rbtree_test.c
@@ -247,7 +247,7 @@ static int __init rbtree_test_init(void)
 	cycles_t time1, time2, time;
 	struct rb_node *node;
 
-	nodes = kmalloc(nnodes * sizeof(*nodes), GFP_KERNEL);
+	nodes = kmalloc_array(nnodes, sizeof(*nodes), GFP_KERNEL);
 	if (!nodes)
 		return -ENOMEM;
 
diff --git a/lib/reed_solomon/reed_solomon.c b/lib/reed_solomon/reed_solomon.c
index dfcf542..d8bb1a1 100644
--- a/lib/reed_solomon/reed_solomon.c
+++ b/lib/reed_solomon/reed_solomon.c
@@ -88,15 +88,15 @@ static struct rs_codec *codec_init(int symsize, int gfpoly, int (*gffunc)(int),
 	rs->gffunc = gffunc;
 
 	/* Allocate the arrays */
-	rs->alpha_to = kmalloc(sizeof(uint16_t) * (rs->nn + 1), gfp);
+	rs->alpha_to = kmalloc_array(rs->nn + 1, sizeof(uint16_t), gfp);
 	if (rs->alpha_to == NULL)
 		goto err;
 
-	rs->index_of = kmalloc(sizeof(uint16_t) * (rs->nn + 1), gfp);
+	rs->index_of = kmalloc_array(rs->nn + 1, sizeof(uint16_t), gfp);
 	if (rs->index_of == NULL)
 		goto err;
 
-	rs->genpoly = kmalloc(sizeof(uint16_t) * (rs->nroots + 1), gfp);
+	rs->genpoly = kmalloc_array(rs->nroots + 1, sizeof(uint16_t), gfp);
 	if(rs->genpoly == NULL)
 		goto err;
 
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index 06dad7a..1642fd5 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -170,7 +170,8 @@ static struct scatterlist *sg_kmalloc(unsigned int nents, gfp_t gfp_mask)
 		kmemleak_alloc(ptr, PAGE_SIZE, 1, gfp_mask);
 		return ptr;
 	} else
-		return kmalloc(nents * sizeof(struct scatterlist), gfp_mask);
+		return kmalloc_array(nents, sizeof(struct scatterlist),
+				     gfp_mask);
 }
 
 static void sg_kfree(struct scatterlist *sg, unsigned int nents)