https://gcc.gnu.org/g:e2d746e5ab73b0b1f1a8104101c09b1f4ab3fa25
commit r14-10492-ge2d746e5ab73b0b1f1a8104101c09b1f4ab3fa25
Author: Peter Bergner <berg...@linux.ibm.com>
Date: Wed Jun 19 16:07:29 2024 -0500
rs6000: ROP - Emit hashst and hashchk insns on Power8 and later [PR114759]
We currently only emit the ROP-protect hash* insns for Power10, where the
insns were added to the architecture. We want to emit them for earlier
cpus (where they operate as NOPs), so that if those older binaries are
ever executed on a Power10, then they'll be protected from ROP attacks.
Binutils accepts hashst and hashchk back to Power8, so change GCC to emit
them for Power8 and later. This matches clang's behavior.
2024-06-19 Peter Bergner <berg...@linux.ibm.com>
gcc/
PR target/114759
* config/rs6000/rs6000-logue.cc (rs6000_stack_info): Use
TARGET_POWER8.
(rs6000_emit_prologue): Likewise.
* config/rs6000/rs6000.md (hashchk): Likewise.
(hashst): Likewise.
Fix whitespace.
gcc/testsuite/
PR target/114759
* gcc.target/powerpc/pr114759-2.c: New test.
* lib/target-supports.exp (rop_ok): Use
check_effective_target_has_arch_pwr8.
(cherry picked from commit a05c3d23d1e1c8d2971b123804fc7a61a3561adb)
Diff:
---
gcc/config/rs6000/rs6000-logue.cc | 6 +++---
gcc/config/rs6000/rs6000.md | 6 +++---
gcc/testsuite/gcc.target/powerpc/pr114759-2.c | 17 +++++++++++++++++
gcc/testsuite/lib/target-supports.exp | 2 +-
4 files changed, 24 insertions(+), 7 deletions(-)
diff --git a/gcc/config/rs6000/rs6000-logue.cc
b/gcc/config/rs6000/rs6000-logue.cc
index 193e2122c0f9..48f406330714 100644
--- a/gcc/config/rs6000/rs6000-logue.cc
+++ b/gcc/config/rs6000/rs6000-logue.cc
@@ -716,7 +716,7 @@ rs6000_stack_info (void)
info->calls_p = (!crtl->is_leaf || cfun->machine->ra_needs_full_frame);
info->rop_hash_size = 0;
- if (TARGET_POWER10
+ if (TARGET_POWER8
&& info->calls_p
&& DEFAULT_ABI == ABI_ELFv2
&& rs6000_rop_protect)
@@ -3272,7 +3272,7 @@ rs6000_emit_prologue (void)
/* NOTE: The hashst isn't needed if we're going to do a sibcall,
but there's no way to know that here. Harmless except for
performance, of course. */
- if (TARGET_POWER10 && rs6000_rop_protect && info->rop_hash_size != 0)
+ if (TARGET_POWER8 && rs6000_rop_protect && info->rop_hash_size != 0)
{
gcc_assert (DEFAULT_ABI == ABI_ELFv2);
rtx stack_ptr = gen_rtx_REG (Pmode, STACK_POINTER_REGNUM);
@@ -5051,7 +5051,7 @@ rs6000_emit_epilogue (enum epilogue_type epilogue_type)
/* The ROP hash check must occur after the stack pointer is restored
(since the hash involves r1), and is not performed for a sibcall. */
- if (TARGET_POWER10
+ if (TARGET_POWER8
&& rs6000_rop_protect
&& info->rop_hash_size != 0
&& epilogue_type != EPILOGUE_TYPE_SIBCALL)
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index d4120c3b9ce5..43bde9ab9e19 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -15815,9 +15815,9 @@
(define_insn "hashst"
[(set (match_operand:DI 0 "simple_offsettable_mem_operand" "=m")
- (unspec_volatile:DI [(match_operand:DI 1 "int_reg_operand" "r")]
+ (unspec_volatile:DI [(match_operand:DI 1 "int_reg_operand" "r")]
UNSPEC_HASHST))]
- "TARGET_POWER10 && rs6000_rop_protect"
+ "TARGET_POWER8 && rs6000_rop_protect"
{
static char templ[32];
const char *p = rs6000_privileged ? "p" : "";
@@ -15830,7 +15830,7 @@
[(unspec_volatile [(match_operand:DI 0 "int_reg_operand" "r")
(match_operand:DI 1 "simple_offsettable_mem_operand" "m")]
UNSPEC_HASHCHK)]
- "TARGET_POWER10 && rs6000_rop_protect"
+ "TARGET_POWER8 && rs6000_rop_protect"
{
static char templ[32];
const char *p = rs6000_privileged ? "p" : "";
diff --git a/gcc/testsuite/gcc.target/powerpc/pr114759-2.c
b/gcc/testsuite/gcc.target/powerpc/pr114759-2.c
new file mode 100644
index 000000000000..3881ebd416e6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr114759-2.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mdejagnu-cpu=power8 -mrop-protect" } */
+/* { dg-require-effective-target rop_ok } Only enable on supported ABIs. */
+
+/* Verify we generate ROP-protect hash insns when compiling for Power8. */
+
+extern void foo (void);
+
+int
+bar (void)
+{
+ foo ();
+ return 5;
+}
+
+/* { dg-final { scan-assembler-times {\mhashst\M} 1 } } */
+/* { dg-final { scan-assembler-times {\mhashchk\M} 1 } } */
diff --git a/gcc/testsuite/lib/target-supports.exp
b/gcc/testsuite/lib/target-supports.exp
index fb9191d6e73b..d8b5a06a4224 100644
--- a/gcc/testsuite/lib/target-supports.exp
+++ b/gcc/testsuite/lib/target-supports.exp
@@ -7393,7 +7393,7 @@ proc check_effective_target_powerpc_elfv2 { } {
# Return 1 if this is a PowerPC target supporting -mrop-protect
proc check_effective_target_rop_ok { } {
- return [check_effective_target_power10_ok] &&
[check_effective_target_powerpc_elfv2]
+ return [check_effective_target_has_arch_pwr8] &&
[check_effective_target_powerpc_elfv2]
}
# The VxWorks SPARC simulator accepts only EM_SPARC executables and
