diff mbox series

[ovs-dev,1/8] datapath: kmalloc() -> kmalloc_array()

Message ID 1544036152-27247-2-git-send-email-gvrose8192@gmail.com
State Superseded
Headers show
Series datapath: Pull in upstream fixes and updates | expand

Commit Message

Gregory Rose Dec. 5, 2018, 6:55 p.m. UTC 
From: Kees Cook <keescook@chromium.org>

Upstream commit:
    commit 6da2ec56059c3c7a7e5f729e6349e74ace1e5c57
    Author: Kees Cook <keescook@chromium.org>
    Date:   Tue Jun 12 13:55:00 2018 -0700

    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>

CC:  Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Rose <gvrose8192@gmail.com>
---
 datapath/datapath.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Comments

0-day Robot Dec. 5, 2018, 7:18 p.m. UTC | #1 
Bleep bloop.  Greetings Greg Rose, I am a robot and I have tried out your patch.
Thanks for your contribution.

I encountered some error that I wasn't expecting.  See the details below.


checkpatch:
ERROR: Author Kees Cook <keescook@chromium.org> needs to sign off.
WARNING: Unexpected sign-offs from developers who are not authors or co-authors or committers: Greg Rose <gvrose8192@gmail.com>
Lines checked: 453, Warnings: 1, Errors: 1


Please check this out.  If you feel there has been an error, please email aconole@bytheb.org

Thanks,
0-day Robot
Gregory Rose Dec. 5, 2018, 8:24 p.m. UTC | #2 
I think this is a false positive due to the upstream commit format we use.

- Greg

On 12/5/2018 11:18 AM, 0-day Robot wrote:
> Bleep bloop.  Greetings Greg Rose, I am a robot and I have tried out your patch.
> Thanks for your contribution.
>
> I encountered some error that I wasn't expecting.  See the details below.
>
>
> checkpatch:
> ERROR: Author Kees Cook <keescook@chromium.org> needs to sign off.
> WARNING: Unexpected sign-offs from developers who are not authors or co-authors or committers: Greg Rose <gvrose8192@gmail.com>
> Lines checked: 453, Warnings: 1, Errors: 1
>
>
> Please check this out.  If you feel there has been an error, please email aconole@bytheb.org
>
> Thanks,
> 0-day Robot
diff mbox series

Patch

diff --git a/datapath/datapath.c b/datapath/datapath.c
index 3f1cdb0..2febcb3 100644
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -1594,8 +1594,9 @@  static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
 		goto err_destroy_table;
 	}
 
-	dp->ports = kmalloc(DP_VPORT_HASH_BUCKETS * sizeof(struct hlist_head),
-			    GFP_KERNEL);
+	dp->ports = kmalloc_array(DP_VPORT_HASH_BUCKETS,
+				  sizeof(struct hlist_head),
+				  GFP_KERNEL);
 	if (!dp->ports) {
 		err = -ENOMEM;
 		goto err_destroy_percpu;