Re: [PATCH] net/sunrpc: Fix return value from proc_do_xprt()

2020-11-07 Thread J. Bruce Fields 
On Sat, Nov 07, 2020 at 01:49:40PM +, Alex Dewar wrote:
> On Fri, Nov 06, 2020 at 05:07:21PM -0500, J. Bruce Fields wrote:
> > Whoops, got 3 independent patches for this and overlooked this one.  See
> > https://lore.kernel.org/linux-nfs/20201106205959.gb26...@fieldses.org/T/#t
> > 
> > --b.
> 
> That looks like a cleaner fix. Thanks for looking anyhow and sorry for
> the noise!

Not noise, all these efforts are appreciated.---b.

> 
> > 
> > On Sat, Oct 24, 2020 at 03:52:40PM +0100, Alex Dewar wrote:
> > > Commit c09f56b8f68d ("net/sunrpc: Fix return value for sysctl
> > > sunrpc.transports") attempted to add error checking for the call to
> > > memory_read_from_buffer(), however its return value was assigned to a
> > > size_t variable, so any negative values would be lost in the cast. Fix
> > > this.
> > > 
> > > Addresses-Coverity-ID: 1498033: Control flow issues (NO_EFFECT)
> > > Fixes: c09f56b8f68d ("net/sunrpc: Fix return value for sysctl 
> > > sunrpc.transports")
> > > Signed-off-by: Alex Dewar 
> > > ---
> > >  net/sunrpc/sysctl.c | 7 +--
> > >  1 file changed, 5 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/net/sunrpc/sysctl.c b/net/sunrpc/sysctl.c
> > > index a18b36b5422d..c95a2b84dd95 100644
> > > --- a/net/sunrpc/sysctl.c
> > > +++ b/net/sunrpc/sysctl.c
> > > @@ -62,6 +62,7 @@ rpc_unregister_sysctl(void)
> > >  static int proc_do_xprt(struct ctl_table *table, int write,
> > >   void *buffer, size_t *lenp, loff_t *ppos)
> > >  {
> > > + ssize_t bytes_read;
> > >   char tmpbuf[256];
> > >   size_t len;
> > >  
> > > @@ -70,12 +71,14 @@ static int proc_do_xprt(struct ctl_table *table, int 
> > > write,
> > >   return 0;
> > >   }
> > >   len = svc_print_xprts(tmpbuf, sizeof(tmpbuf));
> > > - *lenp = memory_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
> > > + bytes_read = memory_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
> > >  
> > > - if (*lenp < 0) {
> > > + if (bytes_read < 0) {
> > >   *lenp = 0;
> > >   return -EINVAL;
> > >   }
> > > +
> > > + *lenp = bytes_read;
> > >   return 0;
> > >  }
> > >  
> > > -- 
> > > 2.29.1

Re: [PATCH] net/sunrpc: Fix return value from proc_do_xprt()

2020-11-07 Thread Alex Dewar 
On Fri, Nov 06, 2020 at 05:07:21PM -0500, J. Bruce Fields wrote:
> Whoops, got 3 independent patches for this and overlooked this one.  See
> https://lore.kernel.org/linux-nfs/20201106205959.gb26...@fieldses.org/T/#t
> 
> --b.

That looks like a cleaner fix. Thanks for looking anyhow and sorry for
the noise!

> 
> On Sat, Oct 24, 2020 at 03:52:40PM +0100, Alex Dewar wrote:
> > Commit c09f56b8f68d ("net/sunrpc: Fix return value for sysctl
> > sunrpc.transports") attempted to add error checking for the call to
> > memory_read_from_buffer(), however its return value was assigned to a
> > size_t variable, so any negative values would be lost in the cast. Fix
> > this.
> > 
> > Addresses-Coverity-ID: 1498033: Control flow issues (NO_EFFECT)
> > Fixes: c09f56b8f68d ("net/sunrpc: Fix return value for sysctl 
> > sunrpc.transports")
> > Signed-off-by: Alex Dewar 
> > ---
> >  net/sunrpc/sysctl.c | 7 +--
> >  1 file changed, 5 insertions(+), 2 deletions(-)
> > 
> > diff --git a/net/sunrpc/sysctl.c b/net/sunrpc/sysctl.c
> > index a18b36b5422d..c95a2b84dd95 100644
> > --- a/net/sunrpc/sysctl.c
> > +++ b/net/sunrpc/sysctl.c
> > @@ -62,6 +62,7 @@ rpc_unregister_sysctl(void)
> >  static int proc_do_xprt(struct ctl_table *table, int write,
> > void *buffer, size_t *lenp, loff_t *ppos)
> >  {
> > +   ssize_t bytes_read;
> > char tmpbuf[256];
> > size_t len;
> >  
> > @@ -70,12 +71,14 @@ static int proc_do_xprt(struct ctl_table *table, int 
> > write,
> > return 0;
> > }
> > len = svc_print_xprts(tmpbuf, sizeof(tmpbuf));
> > -   *lenp = memory_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
> > +   bytes_read = memory_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
> >  
> > -   if (*lenp < 0) {
> > +   if (bytes_read < 0) {
> > *lenp = 0;
> > return -EINVAL;
> > }
> > +
> > +   *lenp = bytes_read;
> > return 0;
> >  }
> >  
> > -- 
> > 2.29.1

Re: [PATCH] net/sunrpc: Fix return value from proc_do_xprt()

2020-11-06 Thread J. Bruce Fields 
Whoops, got 3 independent patches for this and overlooked this one.  See
https://lore.kernel.org/linux-nfs/20201106205959.gb26...@fieldses.org/T/#t

--b.

On Sat, Oct 24, 2020 at 03:52:40PM +0100, Alex Dewar wrote:
> Commit c09f56b8f68d ("net/sunrpc: Fix return value for sysctl
> sunrpc.transports") attempted to add error checking for the call to
> memory_read_from_buffer(), however its return value was assigned to a
> size_t variable, so any negative values would be lost in the cast. Fix
> this.
> 
> Addresses-Coverity-ID: 1498033: Control flow issues (NO_EFFECT)
> Fixes: c09f56b8f68d ("net/sunrpc: Fix return value for sysctl 
> sunrpc.transports")
> Signed-off-by: Alex Dewar 
> ---
>  net/sunrpc/sysctl.c | 7 +--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/net/sunrpc/sysctl.c b/net/sunrpc/sysctl.c
> index a18b36b5422d..c95a2b84dd95 100644
> --- a/net/sunrpc/sysctl.c
> +++ b/net/sunrpc/sysctl.c
> @@ -62,6 +62,7 @@ rpc_unregister_sysctl(void)
>  static int proc_do_xprt(struct ctl_table *table, int write,
>   void *buffer, size_t *lenp, loff_t *ppos)
>  {
> + ssize_t bytes_read;
>   char tmpbuf[256];
>   size_t len;
>  
> @@ -70,12 +71,14 @@ static int proc_do_xprt(struct ctl_table *table, int 
> write,
>   return 0;
>   }
>   len = svc_print_xprts(tmpbuf, sizeof(tmpbuf));
> - *lenp = memory_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
> + bytes_read = memory_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
>  
> - if (*lenp < 0) {
> + if (bytes_read < 0) {
>   *lenp = 0;
>   return -EINVAL;
>   }
> +
> + *lenp = bytes_read;
>   return 0;
>  }
>  
> -- 
> 2.29.1