Re: [PATCH v2] arm64: mops: Do not dereference src reg for a set operation
From: Catalin Marinas
Date: Fri Mar 28 2025 - 16:08:10 EST
On Wed, 26 Mar 2025 11:04:47 +0000, Keir Fraser wrote:
> The source register is not used for SET* and reading it can result in
> a UBSAN out-of-bounds array access error, specifically when the MOPS
> exception is taken from a SET* sequence with XZR (reg 31) as the
> source. Architecturally this is the only case where a src/dst/size
> field in the ESR can be reported as 31.
>
> Prior to 2de451a329cf662b the code in do_el0_mops() was benign as the
> use of pt_regs_read_reg() prevented the out-of-bounds access.
>
> [...]
Applied to arm64 (for-next/core), thanks!
[1/1] arm64: mops: Do not dereference src reg for a set operation
https://git.kernel.org/arm64/c/a13bfa4fe0d6
--
Catalin