From: Szabolcs Nagy Date: Thu, 11 Jun 2020 17:19:40 +0000 (+0100) Subject: aarch64: add NEWS entry about branch protection support X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fheads%2Fnsz%2Fpacbti-v6;p=thirdparty%2Fglibc.git aarch64: add NEWS entry about branch protection support This is a new security feature that relies on architecture extensions and needs glibc to be built with a gcc configured with branch protection. --- diff --git a/NEWS b/NEWS index a660fc59a89..7d0ca3f5202 100644 --- a/NEWS +++ b/NEWS @@ -31,6 +31,18 @@ Major new features: pthread_attr_getsigmask_np have been added. They allow applications to specify the signal mask of a thread created with pthread_create. +* AArch64 now supports standard branch protection security hardening + in glibc when it is built with a GCC that is configured with + --enable-standard-branch-protection. This includes branch target + identification (BTI) and pointer authentication for return addresses + (PAC-RET). They require armv8.5-a and armv8.3-a architecture + extensions respectively for the protection to be effective, + otherwise the used instructions are nops. User code can use PAC-RET + without libc support, but BTI requires a libc that is built with BTI + support, otherwise runtime objects linked into user code will not be + BTI compatible. It is recommended to use GCC 10 or newer when + building glibc with branch protection. + Deprecated and removed features, and other changes affecting compatibility: * The deprecated header and the sysctl function have been