[PATCH v5 14/14] aarch64: add NEWS entry about branch protection support
Szabolcs Nagy
szabolcs.nagy@arm.com
Mon Jun 22 14:01:28 GMT 2020
This is a new security feature that relies on architecture
extensions and needs glibc to be built with a gcc configured
with branch protection.
---
NEWS | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/NEWS b/NEWS
index a660fc59a8..7d0ca3f520 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 <sys/sysctl.h> header and the sysctl function have been
--
2.17.1
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