Re: [PATCH] Fix overflow of name in struct net_device, replaced str* and sprintf with strn* and snprintf respectivly.

On Tue, 2011-03-15 at 20:30 +0530, Sasikanth V wrote:

On Tue, Mar 15, 2011 at 1:59 AM, Ben Hutchings
[off-list ref] wrote:
        On Tue, 2011-03-15 at 01:37 +0530, Sasikanth V wrote:
        > Signed-off-by: Sasikanth V [off-list ref]
        > ---
        >  net/core/dev.c |   14 +++++++-------
        >  1 files changed, 7 insertions(+), 7 deletions(-)
        >
        > diff --git a/net/core/dev.c b/net/core/dev.c
        > index 6561021..9d06c1e 100644
        > --- a/net/core/dev.c
        > +++ b/net/core/dev.c
        > @@ -510,7 +510,7 @@ int netdev_boot_setup_check(struct
        net_device *dev)
        >
        >       for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
        >               if (s[i].name[0] != '\0' && s[i].name[0] != '
        ' &&
        > -                 !strcmp(dev->name, s[i].name)) {
        > +                 !strncmp(dev->name, s[i].name, IFNAMSIZ))
        {
        
        
        If s[i].name is too long, so what?  No change is required
        here.
        
        >                       dev->irq        = s[i].map.irq;
        >                       dev->base_addr  = s[i].map.base_addr;
        >                       dev->mem_start  = s[i].map.mem_start;
        > @@ -539,7 +539,7 @@ unsigned long netdev_boot_base(const
        char *prefix, int unit)
        >       char name[IFNAMSIZ];
        >       int i;
        >
        > -     sprintf(name, "%s%d", prefix, unit);
        > +     snprintf(name, IFNAMSIZ, "%s%d", prefix, unit);
        
        
        This looks reasonable.
        
        >       /*
        >        * If device already registered then return base of 1
        > @@ -549,7 +549,7 @@ unsigned long netdev_boot_base(const
        char *prefix, int unit)
        >               return 1;
        >
        >       for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
        > -             if (!strcmp(name, s[i].name))
        > +             if (!strncmp(name, s[i].name, IFNAMSIZ))
        
        
        Not required.

       So,  Do we have to remove already existing strncmp (to compare
the device name)  in dev.c?

[...]

I don't know what you mean.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.