Re: [PATCH v3] crypto: arm64: Use x16 with indirect branch to bti_c

From: Catalin Marinas
Date: Tue Oct 06 2020 - 13:31:21 EST


On Tue, 6 Oct 2020 11:33:26 -0500, Jeremy Linton wrote:
> The AES code uses a 'br x7' as part of a function called by
> a macro. That branch needs a bti_j as a target. This results
> in a panic as seen below. Using x16 (or x17) with an indirect
> branch keeps the target bti_c.
>
> Bad mode in Synchronous Abort handler detected on CPU1, code 0x34000003 -- BTI
> CPU: 1 PID: 265 Comm: cryptomgr_test Not tainted 5.8.11-300.fc33.aarch64 #1
> pstate: 20400c05 (nzCv daif +PAN -UAO BTYPE=j-)
> pc : aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs]
> lr : aesbs_xts_encrypt+0x48/0xe0 [aes_neon_bs]
> sp : ffff80001052b730
>
> [...]

Applied to arm64 (for-next/fixes), thanks!

[1/1] crypto: arm64: Use x16 with indirect branch to bti_c
https://git.kernel.org/arm64/c/39e4716caa59

--
Catalin