| Message ID | 20230109223818.1706292-1-quic_bjorande@quicinc.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | rpmsg: glink: Release driver_override | expand |
On 1/9/2023 2:38 PM, Bjorn Andersson wrote: > Upon termination of the rpmsg_device, driver_override needs to be freed > to avoid leaking the potentially assigned string. > > Fixes: 42cd402b8fd4 ("rpmsg: Fix kfree() of static memory on setting driver_override") > Fixes: 39e47767ec9b ("rpmsg: Add driver_override device attribute for rpmsg_device") > Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com> > --- > drivers/rpmsg/qcom_glink_native.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c > index 8620eea1dc8a..046271e439c5 100644 > --- a/drivers/rpmsg/qcom_glink_native.c > +++ b/drivers/rpmsg/qcom_glink_native.c > @@ -1454,6 +1454,7 @@ static void qcom_glink_rpdev_release(struct device *dev) > { > struct rpmsg_device *rpdev = to_rpmsg_device(dev); > > + kfree(rpdev->driver_override); I see in Krzysztof's original patch to fix up the driver_override we do kfree in other areas of rpmsg. More of a just curious as to why don't we use the driver_set_override function to clear the string? It's mentioned in the rpmsg header that the helper should be used. --- include/linux/rpmsg.h * @driver_override: driver name to force a match; do not set directly, * because core frees it; use driver_set_override() to * set or clear it. > kfree(rpdev); > } > > @@ -1697,6 +1698,7 @@ static void qcom_glink_device_release(struct device *dev) > > /* Release qcom_glink_alloc_channel() reference */ > kref_put(&channel->refcount, qcom_glink_channel_release); > + kfree(rpdev->driver_override); > kfree(rpdev); > } > >
On Tue, Jan 17, 2023 at 05:01:01PM -0800, Chris Lew wrote: > > > On 1/9/2023 2:38 PM, Bjorn Andersson wrote: > > Upon termination of the rpmsg_device, driver_override needs to be freed > > to avoid leaking the potentially assigned string. > > > > Fixes: 42cd402b8fd4 ("rpmsg: Fix kfree() of static memory on setting driver_override") > > Fixes: 39e47767ec9b ("rpmsg: Add driver_override device attribute for rpmsg_device") > > Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com> > > --- > > drivers/rpmsg/qcom_glink_native.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c > > index 8620eea1dc8a..046271e439c5 100644 > > --- a/drivers/rpmsg/qcom_glink_native.c > > +++ b/drivers/rpmsg/qcom_glink_native.c > > @@ -1454,6 +1454,7 @@ static void qcom_glink_rpdev_release(struct device *dev) > > { > > struct rpmsg_device *rpdev = to_rpmsg_device(dev); > > + kfree(rpdev->driver_override); > > I see in Krzysztof's original patch to fix up the driver_override we do > kfree in other areas of rpmsg. > Right, in the original patch what became driver_set_override() was open coded and hence there was a kfree(). > More of a just curious as to why don't we use the driver_set_override > function to clear the string? It's mentioned in the rpmsg header that the > helper should be used. > > --- include/linux/rpmsg.h > * @driver_override: driver name to force a match; do not set directly, > * because core frees it; use driver_set_override() to > * set or clear it. > Looking around the kernel, just calling kfree() in the release function seems to be how others are doing it as well. As such I presume that comment applies to the runtime state, rather than while we're cleaning things up. Regards, Bjorn > > kfree(rpdev); > > } > > @@ -1697,6 +1698,7 @@ static void qcom_glink_device_release(struct device *dev) > > /* Release qcom_glink_alloc_channel() reference */ > > kref_put(&channel->refcount, qcom_glink_channel_release); > > + kfree(rpdev->driver_override); > > kfree(rpdev); > > } > >
On 1/18/2023 9:50 AM, Bjorn Andersson wrote: > On Tue, Jan 17, 2023 at 05:01:01PM -0800, Chris Lew wrote: >> >> >> On 1/9/2023 2:38 PM, Bjorn Andersson wrote: >>> Upon termination of the rpmsg_device, driver_override needs to be freed >>> to avoid leaking the potentially assigned string. >>> >>> Fixes: 42cd402b8fd4 ("rpmsg: Fix kfree() of static memory on setting driver_override") >>> Fixes: 39e47767ec9b ("rpmsg: Add driver_override device attribute for rpmsg_device") >>> Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com> >>> --- >>> drivers/rpmsg/qcom_glink_native.c | 2 ++ >>> 1 file changed, 2 insertions(+) >>> >>> diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c >>> index 8620eea1dc8a..046271e439c5 100644 >>> --- a/drivers/rpmsg/qcom_glink_native.c >>> +++ b/drivers/rpmsg/qcom_glink_native.c >>> @@ -1454,6 +1454,7 @@ static void qcom_glink_rpdev_release(struct device *dev) >>> { >>> struct rpmsg_device *rpdev = to_rpmsg_device(dev); >>> + kfree(rpdev->driver_override); >> >> I see in Krzysztof's original patch to fix up the driver_override we do >> kfree in other areas of rpmsg. >> > > Right, in the original patch what became driver_set_override() was open > coded and hence there was a kfree(). > >> More of a just curious as to why don't we use the driver_set_override >> function to clear the string? It's mentioned in the rpmsg header that the >> helper should be used. >> >> --- include/linux/rpmsg.h >> * @driver_override: driver name to force a match; do not set directly, >> * because core frees it; use driver_set_override() to >> * set or clear it. >> > > Looking around the kernel, just calling kfree() in the release function > seems to be how others are doing it as well. As such I presume that > comment applies to the runtime state, rather than while we're cleaning > things up. > > Regards, > Bjorn > Got it - should be safe to follow how others are handling this in cleanup. Reviewed-by: Chris Lew <quic_clew@quicinc.com> >>> kfree(rpdev); >>> } >>> @@ -1697,6 +1698,7 @@ static void qcom_glink_device_release(struct device *dev) >>> /* Release qcom_glink_alloc_channel() reference */ >>> kref_put(&channel->refcount, qcom_glink_channel_release); >>> + kfree(rpdev->driver_override); >>> kfree(rpdev); >>> } >>>
diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c index 8620eea1dc8a..046271e439c5 100644 --- a/drivers/rpmsg/qcom_glink_native.c +++ b/drivers/rpmsg/qcom_glink_native.c @@ -1454,6 +1454,7 @@ static void qcom_glink_rpdev_release(struct device *dev) { struct rpmsg_device *rpdev = to_rpmsg_device(dev); + kfree(rpdev->driver_override); kfree(rpdev); } @@ -1697,6 +1698,7 @@ static void qcom_glink_device_release(struct device *dev) /* Release qcom_glink_alloc_channel() reference */ kref_put(&channel->refcount, qcom_glink_channel_release); + kfree(rpdev->driver_override); kfree(rpdev); }
Upon termination of the rpmsg_device, driver_override needs to be freed to avoid leaking the potentially assigned string. Fixes: 42cd402b8fd4 ("rpmsg: Fix kfree() of static memory on setting driver_override") Fixes: 39e47767ec9b ("rpmsg: Add driver_override device attribute for rpmsg_device") Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com> --- drivers/rpmsg/qcom_glink_native.c | 2 ++ 1 file changed, 2 insertions(+)