Re: [PATCH v2] random: vDSO: Avoid call to memset() when zeroing reserved in __cvdso_getrandom_data()
From: Nathan Chancellor
Date: Sat Sep 26 2026 - 08:19:46 EST
On Sat, Sep 26, 2026 at 11:39:43AM +0200, Andreas Schwab wrote:
> On Sep 25 2026, Nathan Chancellor wrote:
>
> > +#if __has_builtin(__builtin_memset_inline)
> > +#define memset_inline(dst, value, size) __builtin_memset_inline(dst, value, size)
> > +#elif IS_ENABLED(CONFIG_CC_HAS_OPT_INLINE_MEMSET)
> > +#define memset_inline(dst, value, size) __builtin_memset(dst, value, size)
> > +#else
> > +static inline void *memset_inline(void *dst, int value, size_t size)
> > +{
> > + char *d = dst;
> > +
> > + while (size--)
> > + *d++ = value;
> > +
> > + return d;
> > +}
> > +#endif
> > +
>
> memset actually returns the original pointer, not the incremented one.
> Nothing uses the return value of memset_inline here, but it is
> confusing.
Whoops, good catch, I guess my fingers gave up on those last two
characters :) I will fix this for v3 once there has been some time for
further review.
--
Cheers,
Nathan