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datapath: kmalloc() -> kmalloc_array()
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Upstream commit:
    commit 6da2ec56059c3c7a7e5f729e6349e74ace1e5c57
    Author: Kees Cook <[email protected]>
    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 <[email protected]>

CC:  Kees Cook <[email protected]>
Acked-by: William Tu <[email protected]>
Signed-off-by: Greg Rose <[email protected]>
Signed-off-by: Ben Pfaff <[email protected]>
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@kees @blp
kees authored and blp committed Dec 15, 2018
1 parent 6aa4a3b commit 8401bb6
Showing 1 changed file with 3 additions and 2 deletions.
5 changes: 3 additions & 2 deletions datapath/datapath.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;
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