Add BTI patch

7107f739398cd96600b039fd748cb1c4822bb400.patch

@@ -0,0 +1,44 @@
+From 7107f739398cd96600b039fd748cb1c4822bb400 Mon Sep 17 00:00:00 2001
+From: Guillaume Gardet <guillaume.gardet@arm.com>
+Date: Fri, 21 Jan 2022 09:26:07 +0100
+Subject: [PATCH] Add BTI landing pads for aarch64
+
+When Branch Target Identifier (BTI) is enabled on aarch64,
+any software which run libglvnd will fail with SIGILL, Illegal instruction.
+This is because some assembler code misses the BTI landing pads.
+See: https://developer.arm.com/documentation/102433/0100/Jump-oriented-programming
+
+"hint #34" is the same thing as "BTI C" landing pad, but keep
+compatibility with systems without BTI enabled.
+---
+ src/GLX/glvnd_genentry.c                     | 1 +
+ src/GLdispatch/vnd-glapi/entry_aarch64_tsd.c | 1 +
+ 2 files changed, 2 insertions(+)
+
+diff --git a/src/GLX/glvnd_genentry.c b/src/GLX/glvnd_genentry.c
+index 7bbe811..b82aa14 100644
+--- a/src/GLX/glvnd_genentry.c
++++ b/src/GLX/glvnd_genentry.c
+@@ -90,6 +90,7 @@ extern char glx_entrypoint_end[];
+ 
+ #define STUB_SIZE 16
+ #define STUB_ASM_ARCH(slot) \
++    "hint #34\n" \
+     "adrp x16, entrypointFunctions + " slot "*8\n" \
+     "ldr x16, [x16, #:lo12:(entrypointFunctions + " slot "*8)]\n" \
+     "br x16\n"
+diff --git a/src/GLdispatch/vnd-glapi/entry_aarch64_tsd.c b/src/GLdispatch/vnd-glapi/entry_aarch64_tsd.c
+index ae80131..a4652e0 100644
+--- a/src/GLdispatch/vnd-glapi/entry_aarch64_tsd.c
++++ b/src/GLdispatch/vnd-glapi/entry_aarch64_tsd.c
+@@ -69,6 +69,7 @@
+  * table then does a branch without link to the function address.
+  */
+ #define STUB_ASM_CODE(slot)                           \
++    "hint #34\n\t"                                    \
+     "stp x1, x0, [sp, #-16]!\n\t"                     \
+     "adrp x0, :got:_glapi_Current\n\t"                \
+     "ldr x0, [x0, #:got_lo12:_glapi_Current]\n\t"     \
+-- 
+GitLab
+