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, 16 insertions, 12 deletions

diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index fc68c7aaef8e..136e7e66d870 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -2743,7 +2743,8 @@ static int create_journal(struct dm_integrity_c *ic, char **error)
 					r = -ENOMEM;
 					goto bad;
 				}
-				section_req->iv = kmalloc(ivsize * 2, GFP_KERNEL);
+				section_req->iv = kmalloc_array(ivsize, 2,
+								GFP_KERNEL);
 				if (!section_req->iv) {
 					skcipher_request_free(section_req);
 					*error = "Unable to allocate iv";
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index f745404da721..97de7a7334d4 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -326,8 +326,8 @@ static int init_origin_hash(void)
 {
 	int i;
 
-	_origins = kmalloc(ORIGIN_HASH_SIZE * sizeof(struct list_head),
-			   GFP_KERNEL);
+	_origins = kmalloc_array(ORIGIN_HASH_SIZE, sizeof(struct list_head),
+				 GFP_KERNEL);
 	if (!_origins) {
 		DMERR("unable to allocate memory for _origins");
 		return -ENOMEM;
@@ -335,8 +335,9 @@ static int init_origin_hash(void)
 	for (i = 0; i < ORIGIN_HASH_SIZE; i++)
 		INIT_LIST_HEAD(_origins + i);
 
-	_dm_origins = kmalloc(ORIGIN_HASH_SIZE * sizeof(struct list_head),
-			      GFP_KERNEL);
+	_dm_origins = kmalloc_array(ORIGIN_HASH_SIZE,
+				    sizeof(struct list_head),
+				    GFP_KERNEL);
 	if (!_dm_origins) {
 		DMERR("unable to allocate memory for _dm_origins");
 		kfree(_origins);
diff --git a/drivers/md/dm-stats.c b/drivers/md/dm-stats.c
index 56059fb56e2d..21de30b4e2a1 100644
--- a/drivers/md/dm-stats.c
+++ b/drivers/md/dm-stats.c
@@ -915,7 +915,9 @@ static int parse_histogram(const char *h, unsigned *n_histogram_entries,
 		if (*q == ',')
 			(*n_histogram_entries)++;
 
-	*histogram_boundaries = kmalloc(*n_histogram_entries * sizeof(unsigned long long), GFP_KERNEL);
+	*histogram_boundaries = kmalloc_array(*n_histogram_entries,
+					      sizeof(unsigned long long),
+					      GFP_KERNEL);
 	if (!*histogram_boundaries)
 		return -ENOMEM;
 
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index caa51dd351b6..938766794c2e 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -561,7 +561,7 @@ static char **realloc_argv(unsigned *size, char **old_argv)
 		new_size = 8;
 		gfp = GFP_NOIO;
 	}
-	argv = kmalloc(new_size * sizeof(*argv), gfp);
+	argv = kmalloc_array(new_size, sizeof(*argv), gfp);
 	if (argv) {
 		memcpy(argv, old_argv, *size * sizeof(*argv));
 		*size = new_size;
diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 239c7bb3929b..01c8329b512d 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -789,8 +789,8 @@ static int bitmap_storage_alloc(struct bitmap_storage *store,
 	num_pages = DIV_ROUND_UP(bytes, PAGE_SIZE);
 	offset = slot_number * num_pages;
 
-	store->filemap = kmalloc(sizeof(struct page *)
-				 * num_pages, GFP_KERNEL);
+	store->filemap = kmalloc_array(num_pages, sizeof(struct page *),
+				       GFP_KERNEL);
 	if (!store->filemap)
 		return -ENOMEM;
 
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 0b344d087581..e7c0ecd19234 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -126,8 +126,8 @@ static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
 	if (!r1_bio)
 		return NULL;
 
-	rps = kmalloc(sizeof(struct resync_pages) * pi->raid_disks,
-		      gfp_flags);
+	rps = kmalloc_array(pi->raid_disks, sizeof(struct resync_pages),
+			    gfp_flags);
 	if (!rps)
 		goto out_free_r1bio;
 
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 1147ae59e3b6..e35db73b9b9e 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -175,7 +175,7 @@ static void * r10buf_pool_alloc(gfp_t gfp_flags, void *data)
 		nalloc_rp = nalloc;
 	else
 		nalloc_rp = nalloc * 2;
-	rps = kmalloc(sizeof(struct resync_pages) * nalloc_rp, gfp_flags);
+	rps = kmalloc_array(nalloc_rp, sizeof(struct resync_pages), gfp_flags);
 	if (!rps)
 		goto out_free_r10bio;