Messages in this thread | | | Date | Fri, 15 Apr 2022 08:14:35 +0200 | From | Dominik Brodowski <> | Subject | Re: [PATCH] random: use memmove instead of memcpy for remaining 32 bytes |
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Am Thu, Apr 14, 2022 at 01:56:49AM +0200 schrieb Jason A. Donenfeld: > In order to immediately overwrite the old key on the stack, before > servicing a userspace request for bytes, we use the remaining 32 bytes > of block 0 as the key. This means moving indices 8,9,a,b,c,d,e,f -> > 4,5,6,7,8,9,a,b. Since 4 < 8, for the kernel implementations of > memcpy(), this doesn't actually appear to be a problem in practice. But > relying on that characteristic seems a bit brittle. So let's change that > to a proper memmove(), which is the by-the-books way of handling > overlapping memory copies. > > Cc: Dominik Brodowski <linux@dominikbrodowski.net> > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Thanks, Dominik
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