Re: [PATCH v2 1/3] x86/uprobes: Fix not using prefixes.nbytes for loop over prefixes.bytes

[Borislav Petkov]

On Thu, Dec 03, 2020 at 12:10:10PM -0600, Tom Lendacky wrote:
> Since that struct is used in multiple places, I think basing it on the array
> size is the best way to go. The main point of the check is just to be sure
> you don't read outside of the array.

Well, what happens if someone increases the array size of:

struct insn_field {
	union {
		insn_byte_t bytes[4];
				^^^^

?

That's why a separate array only for legacy prefixes would be better
in the long run. The array size check is good as a short-term fix for
stable.

I'd say.

-- 
Regards/Gruss,
    Boris.

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