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>

4 files changed, 17 insertions, 12 deletions

diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
index 9a51710..d4e45ad 100644
--- a/fs/ubifs/lpt.c
+++ b/fs/ubifs/lpt.c
@@ -628,7 +628,7 @@ int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
 	/* Needed by 'ubifs_pack_lsave()' */
 	c->main_first = c->leb_cnt - *main_lebs;
 
-	lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_KERNEL);
+	lsave = kmalloc_array(c->lsave_cnt, sizeof(int), GFP_KERNEL);
 	pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_KERNEL);
 	nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_KERNEL);
 	buf = vmalloc(c->leb_size);
@@ -1636,15 +1636,17 @@ static int lpt_init_rd(struct ubifs_info *c)
 		return -ENOMEM;
 
 	for (i = 0; i < LPROPS_HEAP_CNT; i++) {
-		c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ,
-					     GFP_KERNEL);
+		c->lpt_heap[i].arr = kmalloc_array(LPT_HEAP_SZ,
+						   sizeof(void *),
+						   GFP_KERNEL);
 		if (!c->lpt_heap[i].arr)
 			return -ENOMEM;
 		c->lpt_heap[i].cnt = 0;
 		c->lpt_heap[i].max_cnt = LPT_HEAP_SZ;
 	}
 
-	c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL);
+	c->dirty_idx.arr = kmalloc_array(LPT_HEAP_SZ, sizeof(void *),
+					 GFP_KERNEL);
 	if (!c->dirty_idx.arr)
 		return -ENOMEM;
 	c->dirty_idx.cnt = 0;
@@ -1697,7 +1699,7 @@ static int lpt_init_wr(struct ubifs_info *c)
 		return -ENOMEM;
 
 	if (c->big_lpt) {
-		c->lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_NOFS);
+		c->lsave = kmalloc_array(c->lsave_cnt, sizeof(int), GFP_NOFS);
 		if (!c->lsave)
 			return -ENOMEM;
 		err = read_lsave(c);
@@ -1939,8 +1941,8 @@ int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
 			return err;
 	}
 
-	path = kmalloc(sizeof(struct lpt_scan_node) * (c->lpt_hght + 1),
-		       GFP_NOFS);
+	path = kmalloc_array(c->lpt_hght + 1, sizeof(struct lpt_scan_node),
+			     GFP_NOFS);
 	if (!path)
 		return -ENOMEM;
 
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 6c397a3..c5466c7 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1196,7 +1196,8 @@ static int mount_ubifs(struct ubifs_info *c)
 	 * never exceed 64.
 	 */
 	err = -ENOMEM;
-	c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL);
+	c->bottom_up_buf = kmalloc_array(BOTTOM_UP_HEIGHT, sizeof(int),
+					 GFP_KERNEL);
 	if (!c->bottom_up_buf)
 		goto out_free;
 
diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c
index ba3d0e0..4a21e7f 100644
--- a/fs/ubifs/tnc.c
+++ b/fs/ubifs/tnc.c
@@ -1104,8 +1104,9 @@ static struct ubifs_znode *dirty_cow_bottom_up(struct ubifs_info *c,
 	ubifs_assert(znode);
 	if (c->zroot.znode->level > BOTTOM_UP_HEIGHT) {
 		kfree(c->bottom_up_buf);
-		c->bottom_up_buf = kmalloc(c->zroot.znode->level * sizeof(int),
-					   GFP_NOFS);
+		c->bottom_up_buf = kmalloc_array(c->zroot.znode->level,
+						 sizeof(int),
+						 GFP_NOFS);
 		if (!c->bottom_up_buf)
 			return ERR_PTR(-ENOMEM);
 		path = c->bottom_up_buf;
diff --git a/fs/ubifs/tnc_commit.c b/fs/ubifs/tnc_commit.c
index aa31f60..a9df94a 100644
--- a/fs/ubifs/tnc_commit.c
+++ b/fs/ubifs/tnc_commit.c
@@ -366,7 +366,8 @@ static int layout_in_gaps(struct ubifs_info *c, int cnt)
 
 	dbg_gc("%d znodes to write", cnt);
 
-	c->gap_lebs = kmalloc(sizeof(int) * (c->lst.idx_lebs + 1), GFP_NOFS);
+	c->gap_lebs = kmalloc_array(c->lst.idx_lebs + 1, sizeof(int),
+				    GFP_NOFS);
 	if (!c->gap_lebs)
 		return -ENOMEM;
 
@@ -674,7 +675,7 @@ static int alloc_idx_lebs(struct ubifs_info *c, int cnt)
 	dbg_cmt("need about %d empty LEBS for TNC commit", leb_cnt);
 	if (!leb_cnt)
 		return 0;
-	c->ilebs = kmalloc(leb_cnt * sizeof(int), GFP_NOFS);
+	c->ilebs = kmalloc_array(leb_cnt, sizeof(int), GFP_NOFS);
 	if (!c->ilebs)
 		return -ENOMEM;
 	for (i = 0; i < leb_cnt; i++) {