Linus,
On Sat, Mar 16, 2013 at 12:44:32PM +0100, Sebastian Hesselbarth wrote:
> From: David Woodhouse <dw...@infradead.org>
>
> While investigating (ab)use of krealloc, David found this bug. It's
> unlikely to occur, but now we detect the condition and error out
> appropriately.
>
> Signed-off-by: David Woodhouse <david.woodho...@intel.com>
> Signed-off-by: Jason Cooper <ja...@lakedaemon.net>
> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselba...@gmail.com>
> ---
> Jason, David,
>
> I tested the patch on Dove and fixed all remaining issues.
>
> Thomas, Gregory, Andrew should test on their platforms, too.
>
> Sebastian
>
> Changes from v2:
> - fix counting of available array space
> - fix return code handling
>
> Changes from v1:
> - correct typo (s/ nt / int /) I should've caught before sending.
>
> drivers/pinctrl/mvebu/pinctrl-mvebu.c | 33
> +++++++++++++++++++++------------
> 1 file changed, 21 insertions(+), 12 deletions(-)
Does this look good to you?
fwiw,
Acked-by: Jason Cooper <ja...@lakedaemon.net>
thx,
Jason.
> ---
> Cc: Jason Cooper <ja...@lakedaemon.net>
> Cc: David Woodhouse <dw...@infradead.org>
> Cc: Sebastian Hesselbarth <sebastian.hesselba...@gmail.com>
> Cc: Thomas Petazzoni <thomas.petazz...@free-electrons.com>
> Cc: Gregory Clement <gregory.clem...@free-electrons.com>
> Cc: Andrew Lunn <and...@lunn.ch>
> Cc: Ezequiel Garcia <ezequiel.gar...@free-electrons.com>
> Cc: Linus Walleij <linus.wall...@linaro.org>
> Cc: Stephen Warren <swar...@wwwdotorg.org>
> Cc: Linux ARM Kernel <linux-arm-ker...@lists.infradead.org>
> Cc: linux-kernel@vger.kernel.org
> ---
> diff --git a/drivers/pinctrl/mvebu/pinctrl-mvebu.c
> b/drivers/pinctrl/mvebu/pinctrl-mvebu.c
> index c689c04..aa77fb7a 100644
> --- a/drivers/pinctrl/mvebu/pinctrl-mvebu.c
> +++ b/drivers/pinctrl/mvebu/pinctrl-mvebu.c
> @@ -478,8 +478,12 @@ static struct pinctrl_ops mvebu_pinctrl_ops = {
> .dt_free_map = mvebu_pinctrl_dt_free_map,
> };
>
> -static int _add_function(struct mvebu_pinctrl_function *funcs, const char
> *name)
> +static int _add_function(struct mvebu_pinctrl_function *funcs, int *funcsize,
> + const char *name)
> {
> + if (*funcsize <= 0)
> + return -EOVERFLOW;
> +
> while (funcs->num_groups) {
> /* function already there */
> if (strcmp(funcs->name, name) == 0) {
> @@ -488,8 +492,12 @@ static int _add_function(struct mvebu_pinctrl_function
> *funcs, const char *name)
> }
> funcs++;
> }
> +
> + /* append new unique function */
> funcs->name = name;
> funcs->num_groups = 1;
> + (*funcsize)--;
> +
> return 0;
> }
>
> @@ -497,12 +505,12 @@ static int mvebu_pinctrl_build_functions(struct
> platform_device *pdev,
> struct mvebu_pinctrl *pctl)
> {
> struct mvebu_pinctrl_function *funcs;
> - int num = 0;
> + int num = 0, funcsize = pctl->desc.npins;
> int n, s;
>
> /* we allocate functions for number of pins and hope
> - * there are less unique functions than pins available */
> - funcs = devm_kzalloc(&pdev->dev, pctl->desc.npins *
> + * there are fewer unique functions than pins available */
> + funcs = devm_kzalloc(&pdev->dev, funcsize *
> sizeof(struct mvebu_pinctrl_function), GFP_KERNEL);
> if (!funcs)
> return -ENOMEM;
> @@ -510,26 +518,27 @@ static int mvebu_pinctrl_build_functions(struct
> platform_device *pdev,
> for (n = 0; n < pctl->num_groups; n++) {
> struct mvebu_pinctrl_group *grp = &pctl->groups[n];
> for (s = 0; s < grp->num_settings; s++) {
> + int ret;
> +
> /* skip unsupported settings on this variant */
> if (pctl->variant &&
> !(pctl->variant & grp->settings[s].variant))
> continue;
>
> /* check for unique functions and count groups */
> - if (_add_function(funcs, grp->settings[s].name))
> + ret = _add_function(funcs, &funcsize,
> + grp->settings[s].name);
> + if (ret == -EOVERFLOW)
> + dev_err(&pdev->dev,
> + "More functions than pins(%d)\n",
> + pctl->desc.npins);
> + if (ret < 0)
> continue;
>
> num++;
> }
> }
>
> - /* with the number of unique functions and it's groups known,
> - reallocate functions and assign group names */
> - funcs = krealloc(funcs, num * sizeof(struct mvebu_pinctrl_function),
> - GFP_KERNEL);
> - if (!funcs)
> - return -ENOMEM;
> -
> pctl->num_functions = num;
> pctl->functions = funcs;
>
> --
> 1.7.10.4
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-ker...@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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