| Message ID | 20180227140926.22996-2-benjamin.gaignard@st.com |
|---|---|
| State | New |
| Headers | show |
| Series | [1/3] driver core: check notifier_call_chain return value | expand |
2018-03-15 18:10 GMT+01:00 Greg KH <gregkh@linuxfoundation.org>: > On Tue, Feb 27, 2018 at 03:09:24PM +0100, Benjamin Gaignard wrote: >> When being notified that a driver is about to be bind a listener >> could return NOTIFY_BAD. >> Check the return to be sure that the driver could be bind. >> >> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> >> --- >> drivers/base/dd.c | 9 ++++++--- >> 1 file changed, 6 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/base/dd.c b/drivers/base/dd.c >> index de6fd092bf2f..9275f2c0fed2 100644 >> --- a/drivers/base/dd.c >> +++ b/drivers/base/dd.c >> @@ -304,9 +304,12 @@ static int driver_sysfs_add(struct device *dev) >> { >> int ret; >> >> - if (dev->bus) >> - blocking_notifier_call_chain(&dev->bus->p->bus_notifier, >> - BUS_NOTIFY_BIND_DRIVER, dev); >> + if (dev->bus) { >> + if (blocking_notifier_call_chain(&dev->bus->p->bus_notifier, >> + BUS_NOTIFY_BIND_DRIVER, dev) == >> + NOTIFY_BAD) >> + return -EINVAL; > > checkpatch does not complain about this? No (even with --strict), it should be indented with tabs > > And what is going to break when we enable this, as we have never checked > this before? I could have miss some occurences but when greping with BUS_NOTIFY_* patern I haven't any problematic cases. When notifiers don't care of the message they almost all return NOTIFY_DONE, some return NOTIFY_OK but none return NOTIFY_BAD. That I wrote the test like "== NOTIFY_BAD" and not "!= NOTIFY_OK". I have checked this list of files (I hope I haven't forgot any occurence) arch/powerpc/kernel/isa-bridge.c arch/powerpc/kernel/iommu.c arch/powerpc/kernel/dma-swiotlb.c arch/powerpc/platforms/pasemi/setup.c arch/powerpc/platforms/512x/pdm360ng.c arch/powerpc/platforms/cell/iommu.c arch/arm/mach-mvebu/coherency.c arch/arm/common/sa1111.c arch/arm/mach-keystone/keystone.c -> this one return NOTIFY_BAD if dev is NULL which is never the case. arch/arm/mach-highbank/highbank.c arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c arch/arm/mach-omap2/omap_device.c drivers/base/power/clock_ops.c drivers/platform/x86/silead_dmi.c drivers/input/serio/i8042.c drivers/input/mouse/psmouse-smbus.c drivers/w1/w1.c drivers/media/platform/soc_camera/sh_mobile_ceu_camera.c drivers/i2c/i2c-dev.c drivers/acpi/acpi_lpss.c drivers/gpu/vga/vgaarb.c drivers/xen/pci.c drivers/xen/xen-pciback/pci_stub.c drivers/xen/arm-device.c drivers/iommu/s390-iommu.c drivers/iommu/iommu.c drivers/iommu/dmar.c drivers/iommu/intel-iommu.c drivers/usb/core/usb.c drivers/s390/cio/ccwgroup.c drivers/net/ethernet/ibm/emac/core.c Benjamin > > thanks, > > greg k-h
diff --git a/drivers/base/dd.c b/drivers/base/dd.c index de6fd092bf2f..9275f2c0fed2 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -304,9 +304,12 @@ static int driver_sysfs_add(struct device *dev) { int ret; - if (dev->bus) - blocking_notifier_call_chain(&dev->bus->p->bus_notifier, - BUS_NOTIFY_BIND_DRIVER, dev); + if (dev->bus) { + if (blocking_notifier_call_chain(&dev->bus->p->bus_notifier, + BUS_NOTIFY_BIND_DRIVER, dev) == + NOTIFY_BAD) + return -EINVAL; + } ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj, kobject_name(&dev->kobj));
When being notified that a driver is about to be bind a listener could return NOTIFY_BAD. Check the return to be sure that the driver could be bind. Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> --- drivers/base/dd.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) -- 2.15.0