From 574e7950bd6b34e9e2cacce18c802b45505d1d0a Mon Sep 17 00:00:00 2001 From: Richard Earnshaw Date: Fri, 18 Jun 2021 17:16:25 +0100 Subject: [PATCH] arm: add erratum mitigation to __gnu_cmse_nonsecure_call [PR102035] Add the recommended erratum mitigation sequence to __gnu_cmse_nonsecure_call for use on Armv8-m.main devices. Since this is in the library code we cannot know in advance whether the core we are running on will be affected by this, so always enable it. libgcc: PR target/102035 * config/arm/cmse_nonsecure_call.S (__gnu_cmse_nonsecure_call): Add vlldm erratum work-around. CVE: CVE-2021-35465 Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=574e7950bd6b34e9e2cacce18c802b45505d1d0a] Signed-off-by: Pgowda --- libgcc/config/arm/cmse_nonsecure_call.S | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/libgcc/config/arm/cmse_nonsecure_call.S b/libgcc/config/arm/cmse_nonsecure_call.S --- a/libgcc/config/arm/cmse_nonsecure_call.S +++ b/libgcc/config/arm/cmse_nonsecure_call.S @@ -102,6 +102,11 @@ blxns r4 #ifdef __ARM_PCS_VFP vpop.f64 {d8-d15} #else +/* VLLDM erratum mitigation sequence. */ +mrs r5, control +tst r5, #8 /* CONTROL_S.SFPA */ +it ne +.inst.w 0xeeb00a40 /* vmovne s0, s0 */ vlldm sp /* Lazy restore of d0-d16 and FPSCR. */ add sp, sp, #0x88 /* Free space used to save floating point registers. */ #endif /* __ARM_PCS_VFP */