Messages in this thread | | | Date | Fri, 22 Mar 2013 12:39:38 -0400 | From | Jason Cooper <> | Subject | Re: [PATCH v3] pinctrl: mvebu: prevent walking off the end of group array |
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Linus,
On Sat, Mar 16, 2013 at 12:44:32PM +0100, Sebastian Hesselbarth wrote: > From: David Woodhouse <dwmw2@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.Woodhouse@intel.com> > Signed-off-by: Jason Cooper <jason@lakedaemon.net> > Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@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 <jason@lakedaemon.net>
thx,
Jason.
> --- > Cc: Jason Cooper <jason@lakedaemon.net> > Cc: David Woodhouse <dwmw2@infradead.org> > Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> > Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> > Cc: Gregory Clement <gregory.clement@free-electrons.com> > Cc: Andrew Lunn <andrew@lunn.ch> > Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> > Cc: Linus Walleij <linus.walleij@linaro.org> > Cc: Stephen Warren <swarren@wwwdotorg.org> > Cc: Linux ARM Kernel <linux-arm-kernel@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-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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