[PATCH -next] usb: gadget: dereference before null check

[PATCH -next] usb: gadget: dereference before null check

[SebinSebastian]

Fix coverity warning dereferencing before null check. _ep and desc is
dereferenced on all paths until the check for null. Move the
initializations after the check for null.
Coverity issue: 1518209

Signed-off-by: SebinSebastian <mailmesebin00@gmail.com>
---
 drivers/usb/gadget/udc/aspeed_udc.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/udc/aspeed_udc.c b/drivers/usb/gadget/udc/aspeed_udc.c
index d75a4e070bf7..96f8193fca15 100644
--- a/drivers/usb/gadget/udc/aspeed_udc.c
+++ b/drivers/usb/gadget/udc/aspeed_udc.c
@@ -341,10 +341,6 @@ static void ast_udc_stop_activity(struct ast_udc_dev *udc)
 static int ast_udc_ep_enable(struct usb_ep *_ep,
 			     const struct usb_endpoint_descriptor *desc)
 {
-	u16 maxpacket = usb_endpoint_maxp(desc);
-	struct ast_udc_ep *ep = to_ast_ep(_ep);
-	struct ast_udc_dev *udc = ep->udc;
-	u8 epnum = usb_endpoint_num(desc);
 	unsigned long flags;
 	u32 ep_conf = 0;
 	u8 dir_in;
@@ -356,6 +352,11 @@ static int ast_udc_ep_enable(struct usb_ep *_ep,
 		return -EINVAL;
 	}

+	u16 maxpacket = usb_endpoint_maxp(desc);
+	struct ast_udc_ep *ep = to_ast_ep(_ep);
+	struct ast_udc_dev *udc = ep->udc;
+	u8 epnum = usb_endpoint_num(desc);
+
 	if (!udc->driver) {
 		EP_DBG(ep, "bogus device state\n");
 		return -ESHUTDOWN;
--
2.34.1


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Re: [PATCH -next] usb: gadget: dereference before null check

[Greg Kroah-Hartman]

On Wed, Jun 29, 2022 at 01:37:25PM +0530, SebinSebastian wrote:
> Fix coverity warning dereferencing before null check. _ep and desc is
> dereferenced on all paths until the check for null. Move the
> initializations after the check for null.
> Coverity issue: 1518209
> 
> Signed-off-by: SebinSebastian <mailmesebin00@gmail.com>
> ---
>  drivers/usb/gadget/udc/aspeed_udc.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/gadget/udc/aspeed_udc.c b/drivers/usb/gadget/udc/aspeed_udc.c
> index d75a4e070bf7..96f8193fca15 100644
> --- a/drivers/usb/gadget/udc/aspeed_udc.c
> +++ b/drivers/usb/gadget/udc/aspeed_udc.c
> @@ -341,10 +341,6 @@ static void ast_udc_stop_activity(struct ast_udc_dev *udc)
>  static int ast_udc_ep_enable(struct usb_ep *_ep,
>  			     const struct usb_endpoint_descriptor *desc)
>  {
> -	u16 maxpacket = usb_endpoint_maxp(desc);
> -	struct ast_udc_ep *ep = to_ast_ep(_ep);
> -	struct ast_udc_dev *udc = ep->udc;
> -	u8 epnum = usb_endpoint_num(desc);
>  	unsigned long flags;
>  	u32 ep_conf = 0;
>  	u8 dir_in;
> @@ -356,6 +352,11 @@ static int ast_udc_ep_enable(struct usb_ep *_ep,
>  		return -EINVAL;
>  	}
> 
> +	u16 maxpacket = usb_endpoint_maxp(desc);
> +	struct ast_udc_ep *ep = to_ast_ep(_ep);
> +	struct ast_udc_dev *udc = ep->udc;
> +	u8 epnum = usb_endpoint_num(desc);
> +
>  	if (!udc->driver) {
>  		EP_DBG(ep, "bogus device state\n");
>  		return -ESHUTDOWN;
> --
> 2.34.1
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- Your patch breaks the build.

- Your patch contains warnings and/or errors noticed by the
  scripts/checkpatch.pl tool.

- This looks like a new version of a previously submitted patch, but you
  did not list below the --- line any changes from the previous version.
  Please read the section entitled "The canonical patch format" in the
  kernel file, Documentation/SubmittingPatches for what needs to be done
  here to properly describe this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.

thanks,

greg k-h's patch email bot

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Re: [PATCH -next] usb: gadget: dereference before null check

[Sebin Sebastian]

On Wed, Jun 29, 2022 at 10:24:07AM +0200, Greg Kroah-Hartman wrote:
> On Wed, Jun 29, 2022 at 01:37:25PM +0530, SebinSebastian wrote:
> > Fix coverity warning dereferencing before null check. _ep and desc is
> > dereferenced on all paths until the check for null. Move the
> > initializations after the check for null.
> > Coverity issue: 1518209
> > 
> > Signed-off-by: SebinSebastian <mailmesebin00@gmail.com>
> > ---
> >  drivers/usb/gadget/udc/aspeed_udc.c | 9 +++++----
> >  1 file changed, 5 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/usb/gadget/udc/aspeed_udc.c b/drivers/usb/gadget/udc/aspeed_udc.c
> > index d75a4e070bf7..96f8193fca15 100644
> > --- a/drivers/usb/gadget/udc/aspeed_udc.c
> > +++ b/drivers/usb/gadget/udc/aspeed_udc.c
> > @@ -341,10 +341,6 @@ static void ast_udc_stop_activity(struct ast_udc_dev *udc)
> >  static int ast_udc_ep_enable(struct usb_ep *_ep,
> >  			     const struct usb_endpoint_descriptor *desc)
> >  {
> > -	u16 maxpacket = usb_endpoint_maxp(desc);
> > -	struct ast_udc_ep *ep = to_ast_ep(_ep);
> > -	struct ast_udc_dev *udc = ep->udc;
> > -	u8 epnum = usb_endpoint_num(desc);
> >  	unsigned long flags;
> >  	u32 ep_conf = 0;
> >  	u8 dir_in;
> > @@ -356,6 +352,11 @@ static int ast_udc_ep_enable(struct usb_ep *_ep,
> >  		return -EINVAL;
> >  	}
> > 
> > +	u16 maxpacket = usb_endpoint_maxp(desc);
> > +	struct ast_udc_ep *ep = to_ast_ep(_ep);
> > +	struct ast_udc_dev *udc = ep->udc;
> > +	u8 epnum = usb_endpoint_num(desc);
> > +
> >  	if (!udc->driver) {
> >  		EP_DBG(ep, "bogus device state\n");
> >  		return -ESHUTDOWN;
> > --
> > 2.34.1
> > 
> 
> Hi,
> 
> This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
> a patch that has triggered this response.  He used to manually respond
> to these common problems, but in order to save his sanity (he kept
> writing the same thing over and over, yet to different people), I was
> created.  Hopefully you will not take offence and will fix the problem
> in your patch and resubmit it so that it can be accepted into the Linux
> kernel tree.
> 
> You are receiving this message because of the following common error(s)
> as indicated below:
> 
> - Your patch breaks the build.
> 
> - Your patch contains warnings and/or errors noticed by the
>   scripts/checkpatch.pl tool.
> 
> - This looks like a new version of a previously submitted patch, but you
>   did not list below the --- line any changes from the previous version.
>   Please read the section entitled "The canonical patch format" in the
>   kernel file, Documentation/SubmittingPatches for what needs to be done
>   here to properly describe this.
> 
> If you wish to discuss this problem further, or you have questions about
> how to resolve this issue, please feel free to respond to this email and
> Greg will reply once he has dug out from the pending patches received
> from other developers.
> 
> thanks,
> 
> greg k-h's patch email bot

I am sorry to keep on bothering with this incorrect patches. I am
running the checkpatch script everytime before I sent any patches. It is
not showing any warnings or errors. Is it because of my name that my
patches are getting rejected? I can see a space missing.


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Re: [PATCH -next] usb: gadget: dereference before null check

[Greg Kroah-Hartman]

On Wed, Jun 29, 2022 at 05:44:55PM +0530, Sebin Sebastian wrote:
> On Wed, Jun 29, 2022 at 10:24:07AM +0200, Greg Kroah-Hartman wrote:
> > On Wed, Jun 29, 2022 at 01:37:25PM +0530, SebinSebastian wrote:
> > > Fix coverity warning dereferencing before null check. _ep and desc is
> > > dereferenced on all paths until the check for null. Move the
> > > initializations after the check for null.
> > > Coverity issue: 1518209
> > > 
> > > Signed-off-by: SebinSebastian <mailmesebin00@gmail.com>
> > > ---
> > >  drivers/usb/gadget/udc/aspeed_udc.c | 9 +++++----
> > >  1 file changed, 5 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/usb/gadget/udc/aspeed_udc.c b/drivers/usb/gadget/udc/aspeed_udc.c
> > > index d75a4e070bf7..96f8193fca15 100644
> > > --- a/drivers/usb/gadget/udc/aspeed_udc.c
> > > +++ b/drivers/usb/gadget/udc/aspeed_udc.c
> > > @@ -341,10 +341,6 @@ static void ast_udc_stop_activity(struct ast_udc_dev *udc)
> > >  static int ast_udc_ep_enable(struct usb_ep *_ep,
> > >  			     const struct usb_endpoint_descriptor *desc)
> > >  {
> > > -	u16 maxpacket = usb_endpoint_maxp(desc);
> > > -	struct ast_udc_ep *ep = to_ast_ep(_ep);
> > > -	struct ast_udc_dev *udc = ep->udc;
> > > -	u8 epnum = usb_endpoint_num(desc);
> > >  	unsigned long flags;
> > >  	u32 ep_conf = 0;
> > >  	u8 dir_in;
> > > @@ -356,6 +352,11 @@ static int ast_udc_ep_enable(struct usb_ep *_ep,
> > >  		return -EINVAL;
> > >  	}
> > > 
> > > +	u16 maxpacket = usb_endpoint_maxp(desc);
> > > +	struct ast_udc_ep *ep = to_ast_ep(_ep);
> > > +	struct ast_udc_dev *udc = ep->udc;
> > > +	u8 epnum = usb_endpoint_num(desc);
> > > +
> > >  	if (!udc->driver) {
> > >  		EP_DBG(ep, "bogus device state\n");
> > >  		return -ESHUTDOWN;
> > > --
> > > 2.34.1
> > > 
> > 
> > Hi,
> > 
> > This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
> > a patch that has triggered this response.  He used to manually respond
> > to these common problems, but in order to save his sanity (he kept
> > writing the same thing over and over, yet to different people), I was
> > created.  Hopefully you will not take offence and will fix the problem
> > in your patch and resubmit it so that it can be accepted into the Linux
> > kernel tree.
> > 
> > You are receiving this message because of the following common error(s)
> > as indicated below:
> > 
> > - Your patch breaks the build.
> > 
> > - Your patch contains warnings and/or errors noticed by the
> >   scripts/checkpatch.pl tool.
> > 
> > - This looks like a new version of a previously submitted patch, but you
> >   did not list below the --- line any changes from the previous version.
> >   Please read the section entitled "The canonical patch format" in the
> >   kernel file, Documentation/SubmittingPatches for what needs to be done
> >   here to properly describe this.
> > 
> > If you wish to discuss this problem further, or you have questions about
> > how to resolve this issue, please feel free to respond to this email and
> > Greg will reply once he has dug out from the pending patches received
> > from other developers.
> > 
> > thanks,
> > 
> > greg k-h's patch email bot
> 
> I am sorry to keep on bothering with this incorrect patches. I am
> running the checkpatch script everytime before I sent any patches. It is
> not showing any warnings or errors. Is it because of my name that my
> patches are getting rejected? I can see a space missing.

Did you test build your patch?  If not, why not?

thanks,

greg k-h

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Re: [PATCH -next] usb: gadget: dereference before null check

[kernel test robot]

Hi SebinSebastian,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on next-20220628]

url:    https://github.com/intel-lab-lkp/linux/commits/SebinSebastian/usb-gadget-dereference-before-null-check/20220629-161008
base:    cb71b93c2dc36d18a8b05245973328d018272cdf
config: mips-allyesconfig (https://download.01.org/0day-ci/archive/20220630/202206300156.qNpjgo9z-lkp@intel.com/config)
compiler: mips-linux-gcc (GCC) 11.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/97ebbd93f269a58b3b5a003898d6e09c29a73ab0
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review SebinSebastian/usb-gadget-dereference-before-null-check/20220629-161008
        git checkout 97ebbd93f269a58b3b5a003898d6e09c29a73ab0
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   drivers/usb/gadget/udc/aspeed_udc.c: In function 'ast_udc_ep_enable':
>> drivers/usb/gadget/udc/aspeed_udc.c:349:22: error: 'ep' undeclared (first use in this function); did you mean '_ep'?
     349 |         if (!_ep || !ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT ||
         |                      ^~
         |                      _ep
   drivers/usb/gadget/udc/aspeed_udc.c:349:22: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/usb/gadget/udc/aspeed_udc.c:350:13: error: 'maxpacket' undeclared (first use in this function)
     350 |             maxpacket == 0 || maxpacket > ep->ep.maxpacket) {
         |             ^~~~~~~~~
   drivers/usb/gadget/udc/aspeed_udc.c:355:9: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
     355 |         u16 maxpacket = usb_endpoint_maxp(desc);
         |         ^~~


vim +349 drivers/usb/gadget/udc/aspeed_udc.c

055276c1320564b Neal Liu       2022-05-23  340  
055276c1320564b Neal Liu       2022-05-23  341  static int ast_udc_ep_enable(struct usb_ep *_ep,
055276c1320564b Neal Liu       2022-05-23  342  			     const struct usb_endpoint_descriptor *desc)
055276c1320564b Neal Liu       2022-05-23  343  {
055276c1320564b Neal Liu       2022-05-23  344  	unsigned long flags;
055276c1320564b Neal Liu       2022-05-23  345  	u32 ep_conf = 0;
055276c1320564b Neal Liu       2022-05-23  346  	u8 dir_in;
055276c1320564b Neal Liu       2022-05-23  347  	u8 type;
055276c1320564b Neal Liu       2022-05-23  348  
055276c1320564b Neal Liu       2022-05-23 @349  	if (!_ep || !ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT ||
055276c1320564b Neal Liu       2022-05-23 @350  	    maxpacket == 0 || maxpacket > ep->ep.maxpacket) {
055276c1320564b Neal Liu       2022-05-23  351  		EP_DBG(ep, "Failed, invalid EP enable param\n");
055276c1320564b Neal Liu       2022-05-23  352  		return -EINVAL;
055276c1320564b Neal Liu       2022-05-23  353  	}
055276c1320564b Neal Liu       2022-05-23  354  
97ebbd93f269a58 SebinSebastian 2022-06-29  355  	u16 maxpacket = usb_endpoint_maxp(desc);
97ebbd93f269a58 SebinSebastian 2022-06-29  356  	struct ast_udc_ep *ep = to_ast_ep(_ep);
97ebbd93f269a58 SebinSebastian 2022-06-29  357  	struct ast_udc_dev *udc = ep->udc;
97ebbd93f269a58 SebinSebastian 2022-06-29  358  	u8 epnum = usb_endpoint_num(desc);
97ebbd93f269a58 SebinSebastian 2022-06-29  359  
055276c1320564b Neal Liu       2022-05-23  360  	if (!udc->driver) {
055276c1320564b Neal Liu       2022-05-23  361  		EP_DBG(ep, "bogus device state\n");
055276c1320564b Neal Liu       2022-05-23  362  		return -ESHUTDOWN;
055276c1320564b Neal Liu       2022-05-23  363  	}
055276c1320564b Neal Liu       2022-05-23  364  
055276c1320564b Neal Liu       2022-05-23  365  	EP_DBG(ep, "maxpacket:0x%x\n", maxpacket);
055276c1320564b Neal Liu       2022-05-23  366  
055276c1320564b Neal Liu       2022-05-23  367  	spin_lock_irqsave(&udc->lock, flags);
055276c1320564b Neal Liu       2022-05-23  368  
055276c1320564b Neal Liu       2022-05-23  369  	ep->desc = desc;
055276c1320564b Neal Liu       2022-05-23  370  	ep->stopped = 0;
055276c1320564b Neal Liu       2022-05-23  371  	ep->ep.maxpacket = maxpacket;
055276c1320564b Neal Liu       2022-05-23  372  	ep->chunk_max = AST_EP_DMA_DESC_MAX_LEN;
055276c1320564b Neal Liu       2022-05-23  373  
055276c1320564b Neal Liu       2022-05-23  374  	if (maxpacket < AST_UDC_EPn_MAX_PACKET)
055276c1320564b Neal Liu       2022-05-23  375  		ep_conf = EP_SET_MAX_PKT(maxpacket);
055276c1320564b Neal Liu       2022-05-23  376  
055276c1320564b Neal Liu       2022-05-23  377  	ep_conf |= EP_SET_EP_NUM(epnum);
055276c1320564b Neal Liu       2022-05-23  378  
055276c1320564b Neal Liu       2022-05-23  379  	type = usb_endpoint_type(desc);
055276c1320564b Neal Liu       2022-05-23  380  	dir_in = usb_endpoint_dir_in(desc);
055276c1320564b Neal Liu       2022-05-23  381  	ep->dir_in = dir_in;
055276c1320564b Neal Liu       2022-05-23  382  	if (!ep->dir_in)
055276c1320564b Neal Liu       2022-05-23  383  		ep_conf |= EP_DIR_OUT;
055276c1320564b Neal Liu       2022-05-23  384  
055276c1320564b Neal Liu       2022-05-23  385  	EP_DBG(ep, "type %d, dir_in %d\n", type, dir_in);
055276c1320564b Neal Liu       2022-05-23  386  	switch (type) {
055276c1320564b Neal Liu       2022-05-23  387  	case USB_ENDPOINT_XFER_ISOC:
055276c1320564b Neal Liu       2022-05-23  388  		ep_conf |= EP_SET_TYPE_MASK(EP_TYPE_ISO);
055276c1320564b Neal Liu       2022-05-23  389  		break;
055276c1320564b Neal Liu       2022-05-23  390  
055276c1320564b Neal Liu       2022-05-23  391  	case USB_ENDPOINT_XFER_BULK:
055276c1320564b Neal Liu       2022-05-23  392  		ep_conf |= EP_SET_TYPE_MASK(EP_TYPE_BULK);
055276c1320564b Neal Liu       2022-05-23  393  		break;
055276c1320564b Neal Liu       2022-05-23  394  
055276c1320564b Neal Liu       2022-05-23  395  	case USB_ENDPOINT_XFER_INT:
055276c1320564b Neal Liu       2022-05-23  396  		ep_conf |= EP_SET_TYPE_MASK(EP_TYPE_INT);
055276c1320564b Neal Liu       2022-05-23  397  		break;
055276c1320564b Neal Liu       2022-05-23  398  	}
055276c1320564b Neal Liu       2022-05-23  399  
055276c1320564b Neal Liu       2022-05-23  400  	ep->desc_mode = udc->desc_mode && ep->descs_dma && ep->dir_in;
055276c1320564b Neal Liu       2022-05-23  401  	if (ep->desc_mode) {
055276c1320564b Neal Liu       2022-05-23  402  		ast_ep_write(ep, EP_DMA_CTRL_RESET, AST_UDC_EP_DMA_CTRL);
055276c1320564b Neal Liu       2022-05-23  403  		ast_ep_write(ep, 0, AST_UDC_EP_DMA_STS);
055276c1320564b Neal Liu       2022-05-23  404  		ast_ep_write(ep, ep->descs_dma, AST_UDC_EP_DMA_BUFF);
055276c1320564b Neal Liu       2022-05-23  405  
055276c1320564b Neal Liu       2022-05-23  406  		/* Enable Long Descriptor Mode */
055276c1320564b Neal Liu       2022-05-23  407  		ast_ep_write(ep, EP_DMA_CTRL_IN_LONG_MODE | EP_DMA_DESC_MODE,
055276c1320564b Neal Liu       2022-05-23  408  			     AST_UDC_EP_DMA_CTRL);
055276c1320564b Neal Liu       2022-05-23  409  
055276c1320564b Neal Liu       2022-05-23  410  		ep->descs_wptr = 0;
055276c1320564b Neal Liu       2022-05-23  411  
055276c1320564b Neal Liu       2022-05-23  412  	} else {
055276c1320564b Neal Liu       2022-05-23  413  		ast_ep_write(ep, EP_DMA_CTRL_RESET, AST_UDC_EP_DMA_CTRL);
055276c1320564b Neal Liu       2022-05-23  414  		ast_ep_write(ep, EP_DMA_SINGLE_STAGE, AST_UDC_EP_DMA_CTRL);
055276c1320564b Neal Liu       2022-05-23  415  		ast_ep_write(ep, 0, AST_UDC_EP_DMA_STS);
055276c1320564b Neal Liu       2022-05-23  416  	}
055276c1320564b Neal Liu       2022-05-23  417  
055276c1320564b Neal Liu       2022-05-23  418  	/* Cleanup data toggle just in case */
055276c1320564b Neal Liu       2022-05-23  419  	ast_udc_write(udc, EP_TOGGLE_SET_EPNUM(epnum), AST_VHUB_EP_DATA);
055276c1320564b Neal Liu       2022-05-23  420  
055276c1320564b Neal Liu       2022-05-23  421  	/* Enable EP */
055276c1320564b Neal Liu       2022-05-23  422  	ast_ep_write(ep, ep_conf | EP_ENABLE, AST_UDC_EP_CONFIG);
055276c1320564b Neal Liu       2022-05-23  423  
055276c1320564b Neal Liu       2022-05-23  424  	EP_DBG(ep, "ep_config: 0x%x\n", ast_ep_read(ep, AST_UDC_EP_CONFIG));
055276c1320564b Neal Liu       2022-05-23  425  
055276c1320564b Neal Liu       2022-05-23  426  	spin_unlock_irqrestore(&udc->lock, flags);
055276c1320564b Neal Liu       2022-05-23  427  
055276c1320564b Neal Liu       2022-05-23  428  	return 0;
055276c1320564b Neal Liu       2022-05-23  429  }
055276c1320564b Neal Liu       2022-05-23  430  

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

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Re: [PATCH -next] usb: gadget: dereference before null check

[Sebin Sebastian]

On Wed, Jun 29, 2022 at 05:31:57PM +0200, Greg Kroah-Hartman wrote:
> On Wed, Jun 29, 2022 at 05:44:55PM +0530, Sebin Sebastian wrote:
> > On Wed, Jun 29, 2022 at 10:24:07AM +0200, Greg Kroah-Hartman wrote:
> > > On Wed, Jun 29, 2022 at 01:37:25PM +0530, SebinSebastian wrote:
> > > > Fix coverity warning dereferencing before null check. _ep and desc is
> > > > dereferenced on all paths until the check for null. Move the
> > > > initializations after the check for null.
> > > > Coverity issue: 1518209
> > > > 
> > > > Signed-off-by: SebinSebastian <mailmesebin00@gmail.com>
> > > > ---
> > > >  drivers/usb/gadget/udc/aspeed_udc.c | 9 +++++----
> > > >  1 file changed, 5 insertions(+), 4 deletions(-)
> > > > 
> > > > diff --git a/drivers/usb/gadget/udc/aspeed_udc.c b/drivers/usb/gadget/udc/aspeed_udc.c
> > > > index d75a4e070bf7..96f8193fca15 100644
> > > > --- a/drivers/usb/gadget/udc/aspeed_udc.c
> > > > +++ b/drivers/usb/gadget/udc/aspeed_udc.c
> > > > @@ -341,10 +341,6 @@ static void ast_udc_stop_activity(struct ast_udc_dev *udc)
> > > >  static int ast_udc_ep_enable(struct usb_ep *_ep,
> > > >  			     const struct usb_endpoint_descriptor *desc)
> > > >  {
> > > > -	u16 maxpacket = usb_endpoint_maxp(desc);
> > > > -	struct ast_udc_ep *ep = to_ast_ep(_ep);
> > > > -	struct ast_udc_dev *udc = ep->udc;
> > > > -	u8 epnum = usb_endpoint_num(desc);
> > > >  	unsigned long flags;
> > > >  	u32 ep_conf = 0;
> > > >  	u8 dir_in;
> > > > @@ -356,6 +352,11 @@ static int ast_udc_ep_enable(struct usb_ep *_ep,
> > > >  		return -EINVAL;
> > > >  	}
> > > > 
> > > > +	u16 maxpacket = usb_endpoint_maxp(desc);
> > > > +	struct ast_udc_ep *ep = to_ast_ep(_ep);
> > > > +	struct ast_udc_dev *udc = ep->udc;
> > > > +	u8 epnum = usb_endpoint_num(desc);
> > > > +
> > > >  	if (!udc->driver) {
> > > >  		EP_DBG(ep, "bogus device state\n");
> > > >  		return -ESHUTDOWN;
> > > > --
> > > > 2.34.1
> > > > 
> > > 
> > > Hi,
> > > 
> > > This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
> > > a patch that has triggered this response.  He used to manually respond
> > > to these common problems, but in order to save his sanity (he kept
> > > writing the same thing over and over, yet to different people), I was
> > > created.  Hopefully you will not take offence and will fix the problem
> > > in your patch and resubmit it so that it can be accepted into the Linux
> > > kernel tree.
> > > 
> > > You are receiving this message because of the following common error(s)
> > > as indicated below:
> > > 
> > > - Your patch breaks the build.
> > > 
> > > - Your patch contains warnings and/or errors noticed by the
> > >   scripts/checkpatch.pl tool.
> > > 
> > > - This looks like a new version of a previously submitted patch, but you
> > >   did not list below the --- line any changes from the previous version.
> > >   Please read the section entitled "The canonical patch format" in the
> > >   kernel file, Documentation/SubmittingPatches for what needs to be done
> > >   here to properly describe this.
> > > 
> > > If you wish to discuss this problem further, or you have questions about
> > > how to resolve this issue, please feel free to respond to this email and
> > > Greg will reply once he has dug out from the pending patches received
> > > from other developers.
> > > 
> > > thanks,
> > > 
> > > greg k-h's patch email bot
> > 
> > I am sorry to keep on bothering with this incorrect patches. I am
> > running the checkpatch script everytime before I sent any patches. It is
> > not showing any warnings or errors. Is it because of my name that my
> > patches are getting rejected? I can see a space missing.
> 
> Did you test build your patch?  If not, why not?
> 
> thanks,
> 
> greg k-h

Ok, now I understand the source of all errors. I did build the entire
tree, but make never touched udc. I have fixed all errors and warnings,
build the patch properly, ran through checkpatch and is now ready for
submission.

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