| Message ID | 20200801220101.2783-1-cengiz@kernel.wtf (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v6] staging: atomisp: move null check to earlier point | expand |
Hello Andy, Can I get some feedback on v6 please? I hope it suits your standards this time. Thank you On August 2, 2020 01:02:22 Cengiz Can <cengiz@kernel.wtf> wrote: > `find_gmin_subdev()` that returns a pointer to `struct > gmin_subdev` can return NULL. > > In `gmin_v2p8_ctrl()` there's a call to this function but the > possibility of a NULL was not checked before its being dereferenced, > i.e.: > > /* Acquired here --------v */ > struct gmin_subdev *gs = find_gmin_subdev(subdev); > > /* v------Dereferenced here */ > if (gs->v2p8_gpio >= 0) { > ... > } > > With this change we're null checking `find_gmin_subdev()` result > and we return an error if that's the case. We also WARN() > for the sake of debugging. > > Signed-off-by: Cengiz Can <cengiz@kernel.wtf> > Reported-by: Coverity Static Analyzer CID 1465536 > Suggested-by: Mauro Carvalho Chehab <mchehab@kernel.org> > --- > > Please do note that this change introduces a new return value to > `gmin_v2p8_ctrl()`. > > [NEW] - raise a WARN and return -ENODEV if there are no subdevices. > - return result of `gpio_request` or `gpio_direction_output`. > - return 0 if GPIO is ON. > - return results of `regulator_enable` or `regulator_disable`. > - according to PMIC type, return result of `axp_regulator_set` > or `gmin_i2c_write`. > - return -EINVAL if unknown PMIC type. > > Patch Changelog: > v4: Fix minor typo in commit message > v5: Remove typo from email subject > v6: Remove duplicate Signed-off-by tag > > drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c > b/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c > index 0df46a1af5f0..1ad0246764a6 100644 > --- a/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c > +++ b/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c > @@ -871,6 +871,9 @@ static int gmin_v2p8_ctrl(struct v4l2_subdev *subdev, > int on) > int ret; > int value; > > + if (WARN_ON(!gs)) > + return -ENODEV; > + > if (gs->v2p8_gpio >= 0) { > pr_info("atomisp_gmin_platform: 2.8v power on GPIO %d\n", > gs->v2p8_gpio); > @@ -881,7 +884,7 @@ static int gmin_v2p8_ctrl(struct v4l2_subdev *subdev, > int on) > pr_err("V2P8 GPIO initialization failed\n"); > } > > - if (!gs || gs->v2p8_on == on) > + if (gs->v2p8_on == on) > return 0; > gs->v2p8_on = on; > > -- > 2.27.0
On Thu, Aug 06, 2020 at 09:34:22PM +0300, Cengiz Can wrote: > Hello Andy, > > Can I get some feedback on v6 please? It's been 4 days, in the middle of a merge window, please give people a chance to catch up on other things... and do not top post please. thanks, greg k-h
On August 6, 2020 21:39:21 Greg KH <gregkh@linuxfoundation.org> wrote: > On Thu, Aug 06, 2020 at 09:34:22PM +0300, Cengiz Can wrote: >> Hello Andy, >> >> Can I get some feedback on v6 please? > > > It's been 4 days, in the middle of a merge window, please give people a > chance to catch up on other things... I wasn't aware of that we're currently in a merge window. Sorry for my impatience. > > and do not top post please. Sorry. I was tricked by my mobile email client. > > thanks, > > greg k-h Thanks again and I wish a smooth merge window to all maintainers. Cengiz Can
diff --git a/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c b/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c index 0df46a1af5f0..1ad0246764a6 100644 --- a/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c +++ b/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c @@ -871,6 +871,9 @@ static int gmin_v2p8_ctrl(struct v4l2_subdev *subdev, int on) int ret; int value; + if (WARN_ON(!gs)) + return -ENODEV; + if (gs->v2p8_gpio >= 0) { pr_info("atomisp_gmin_platform: 2.8v power on GPIO %d\n", gs->v2p8_gpio); @@ -881,7 +884,7 @@ static int gmin_v2p8_ctrl(struct v4l2_subdev *subdev, int on) pr_err("V2P8 GPIO initialization failed\n"); } - if (!gs || gs->v2p8_on == on) + if (gs->v2p8_on == on) return 0; gs->v2p8_on = on;
`find_gmin_subdev()` that returns a pointer to `struct gmin_subdev` can return NULL. In `gmin_v2p8_ctrl()` there's a call to this function but the possibility of a NULL was not checked before its being dereferenced, i.e.: /* Acquired here --------v */ struct gmin_subdev *gs = find_gmin_subdev(subdev); /* v------Dereferenced here */ if (gs->v2p8_gpio >= 0) { ... } With this change we're null checking `find_gmin_subdev()` result and we return an error if that's the case. We also WARN() for the sake of debugging. Signed-off-by: Cengiz Can <cengiz@kernel.wtf> Reported-by: Coverity Static Analyzer CID 1465536 Suggested-by: Mauro Carvalho Chehab <mchehab@kernel.org> --- Please do note that this change introduces a new return value to `gmin_v2p8_ctrl()`. [NEW] - raise a WARN and return -ENODEV if there are no subdevices. - return result of `gpio_request` or `gpio_direction_output`. - return 0 if GPIO is ON. - return results of `regulator_enable` or `regulator_disable`. - according to PMIC type, return result of `axp_regulator_set` or `gmin_i2c_write`. - return -EINVAL if unknown PMIC type. Patch Changelog: v4: Fix minor typo in commit message v5: Remove typo from email subject v6: Remove duplicate Signed-off-by tag drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)