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[PATCH] i386: Insert ENDBR after __morestack call
- From: "H.J. Lu" <hongjiu dot lu at intel dot com>
- To: gcc-patches at gcc dot gnu dot org
- Cc: Uros Bizjak <ubizjak at gmail dot com>
- Date: Fri, 13 Apr 2018 05:56:43 -0700
- Subject: [PATCH] i386: Insert ENDBR after __morestack call
- Reply-to: "H.J. Lu" <hjl dot tools at gmail dot com>
Since __morestack will jump back to its callee via indirect call, we
need to insert ENDBR after calling __morestack.
OK for trunk?
H.J.
----
gcc/
PR target/85388
* config/i386/i386.c (ix86_expand_split_stack_prologue): Insert
ENDBR after calling __morestack.
gcc/testsuite/
PR target/85388
* gcc.dg/pr85388-1.c: New test.
* gcc.dg/pr85388-2.c: Likewise.
* gcc.dg/pr85388-3.c: Likewise.
* gcc.dg/pr85388-4.c: Likewise.
* gcc.dg/pr85388-5.c: Likewise.
* gcc.dg/pr85388-6.c: Likewise.
---
gcc/config/i386/i386.c | 11 ++++++-
gcc/testsuite/gcc.dg/pr85388-1.c | 50 +++++++++++++++++++++++++++++
gcc/testsuite/gcc.dg/pr85388-2.c | 56 ++++++++++++++++++++++++++++++++
gcc/testsuite/gcc.dg/pr85388-3.c | 65 +++++++++++++++++++++++++++++++++++++
gcc/testsuite/gcc.dg/pr85388-4.c | 69 ++++++++++++++++++++++++++++++++++++++++
gcc/testsuite/gcc.dg/pr85388-5.c | 54 +++++++++++++++++++++++++++++++
gcc/testsuite/gcc.dg/pr85388-6.c | 56 ++++++++++++++++++++++++++++++++
7 files changed, 360 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/pr85388-1.c
create mode 100644 gcc/testsuite/gcc.dg/pr85388-2.c
create mode 100644 gcc/testsuite/gcc.dg/pr85388-3.c
create mode 100644 gcc/testsuite/gcc.dg/pr85388-4.c
create mode 100644 gcc/testsuite/gcc.dg/pr85388-5.c
create mode 100644 gcc/testsuite/gcc.dg/pr85388-6.c
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 03e5c433574..8b4fd8ae30b 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -15242,7 +15242,16 @@ ix86_expand_split_stack_prologue (void)
instruction--we need control flow to continue at the subsequent
label. Therefore, we use an unspec. */
gcc_assert (crtl->args.pops_args < 65536);
- emit_insn (gen_split_stack_return (GEN_INT (crtl->args.pops_args)));
+ rtx_insn *ret_insn
+ = emit_insn (gen_split_stack_return (GEN_INT (crtl->args.pops_args)));
+
+ if ((flag_cf_protection & CF_BRANCH) && TARGET_IBT)
+ {
+ /* Insert ENDBR since __morestack will jump back here via indirect
+ call. */
+ rtx cet_eb = gen_nop_endbr ();
+ emit_insn_after (cet_eb, ret_insn);
+ }
/* If we are in 64-bit mode and this function uses a static chain,
we saved %r10 in %rax before calling _morestack. */
diff --git a/gcc/testsuite/gcc.dg/pr85388-1.c b/gcc/testsuite/gcc.dg/pr85388-1.c
new file mode 100644
index 00000000000..86d4737e32b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr85388-1.c
@@ -0,0 +1,50 @@
+/* This test needs to use setrlimit to set the stack size, so it can
+ only run on Unix. */
+/* { dg-do run { target { i?86-*-linux* i?86-*-gnu* x86_64-*-linux* } } } */
+/* { dg-require-effective-target cet } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-options "-fsplit-stack -fcf-protection -mcet" } */
+
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/resource.h>
+
+/* Use a noinline function to ensure that the buffer is not removed
+ from the stack. */
+static void use_buffer (char *buf) __attribute__ ((noinline));
+static void
+use_buffer (char *buf)
+{
+ buf[0] = '\0';
+}
+
+/* Each recursive call uses 10,000 bytes. We call it 1000 times,
+ using a total of 10,000,000 bytes. If -fsplit-stack is not
+ working, that will overflow our stack limit. */
+
+static void
+down (int i)
+{
+ char buf[10000];
+
+ if (i > 0)
+ {
+ use_buffer (buf);
+ down (i - 1);
+ }
+}
+
+int
+main (void)
+{
+ struct rlimit r;
+
+ /* We set a stack limit because we are usually invoked via make, and
+ make sets the stack limit to be as large as possible. */
+ r.rlim_cur = 8192 * 1024;
+ r.rlim_max = 8192 * 1024;
+ if (setrlimit (RLIMIT_STACK, &r) != 0)
+ abort ();
+ down (1000);
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/pr85388-2.c b/gcc/testsuite/gcc.dg/pr85388-2.c
new file mode 100644
index 00000000000..fd13d984c50
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr85388-2.c
@@ -0,0 +1,56 @@
+/* { dg-do run { target { i?86-*-linux* i?86-*-gnu* x86_64-*-linux* } } } */
+/* { dg-require-effective-target cet } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-require-effective-target pthread_h } */
+/* { dg-options "-pthread -fsplit-stack -fcf-protection -mcet" } */
+
+#include <stdlib.h>
+#include <pthread.h>
+
+/* Use a noinline function to ensure that the buffer is not removed
+ from the stack. */
+static void use_buffer (char *buf) __attribute__ ((noinline));
+static void
+use_buffer (char *buf)
+{
+ buf[0] = '\0';
+}
+
+/* Each recursive call uses 10,000 bytes. We call it 1000 times,
+ using a total of 10,000,000 bytes. If -fsplit-stack is not
+ working, that will overflow our stack limit. */
+
+static void
+down (int i)
+{
+ char buf[10000];
+
+ if (i > 0)
+ {
+ use_buffer (buf);
+ down (i - 1);
+ }
+}
+
+static void *
+thread_routine (void *arg __attribute__ ((unused)))
+{
+ down (1000);
+ return NULL;
+}
+
+int
+main (void)
+{
+ int i;
+ pthread_t tid;
+ void *dummy;
+
+ i = pthread_create (&tid, NULL, thread_routine, NULL);
+ if (i != 0)
+ abort ();
+ i = pthread_join (tid, &dummy);
+ if (i != 0)
+ abort ();
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/pr85388-3.c b/gcc/testsuite/gcc.dg/pr85388-3.c
new file mode 100644
index 00000000000..730d2be9c22
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr85388-3.c
@@ -0,0 +1,65 @@
+/* This test needs to use setrlimit to set the stack size, so it can
+ only run on Unix. */
+/* { dg-do run { target { i?86-*-linux* i?86-*-gnu* x86_64-*-linux* } } } */
+/* { dg-require-effective-target cet } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-options "-fsplit-stack -fcf-protection -mcet" } */
+
+#include <stdarg.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/resource.h>
+
+/* Use a noinline function to ensure that the buffer is not removed
+ from the stack. */
+static void use_buffer (char *buf) __attribute__ ((noinline));
+static void
+use_buffer (char *buf)
+{
+ buf[0] = '\0';
+}
+
+/* Each recursive call uses 10,000 bytes. We call it 1000 times,
+ using a total of 10,000,000 bytes. If -fsplit-stack is not
+ working, that will overflow our stack limit. */
+
+static void
+down (int i, ...)
+{
+ char buf[10000];
+ va_list ap;
+
+ va_start (ap, i);
+ if (va_arg (ap, int) != 1
+ || va_arg (ap, int) != 2
+ || va_arg (ap, int) != 3
+ || va_arg (ap, int) != 4
+ || va_arg (ap, int) != 5
+ || va_arg (ap, int) != 6
+ || va_arg (ap, int) != 7
+ || va_arg (ap, int) != 8
+ || va_arg (ap, int) != 9
+ || va_arg (ap, int) != 10)
+ abort ();
+
+ if (i > 0)
+ {
+ use_buffer (buf);
+ down (i - 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+ }
+}
+
+int
+main (void)
+{
+ struct rlimit r;
+
+ /* We set a stack limit because we are usually invoked via make, and
+ make sets the stack limit to be as large as possible. */
+ r.rlim_cur = 8192 * 1024;
+ r.rlim_max = 8192 * 1024;
+ if (setrlimit (RLIMIT_STACK, &r) != 0)
+ abort ();
+ down (1000, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/pr85388-4.c b/gcc/testsuite/gcc.dg/pr85388-4.c
new file mode 100644
index 00000000000..03937d0e735
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr85388-4.c
@@ -0,0 +1,69 @@
+/* This test needs to use setrlimit to set the stack size, so it can
+ only run on Unix. */
+/* { dg-do run { target { i?86-*-linux* i?86-*-gnu* x86_64-*-linux* } } } */
+/* { dg-require-effective-target cet } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-options "-fsplit-stack -fcf-protection -mcet" } */
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/resource.h>
+
+/* Use a noinline function to ensure that the buffer is not removed
+ from the stack. */
+static void use_buffer (char *buf, size_t) __attribute__ ((noinline));
+static void
+use_buffer (char *buf, size_t c)
+{
+ size_t i;
+
+ for (i = 0; i < c; ++i)
+ buf[i] = (char) i;
+}
+
+/* Each recursive call uses 10 * i bytes. We call it 1000 times,
+ using a total of 5,000,000 bytes. If -fsplit-stack is not working,
+ that will overflow our stack limit. */
+
+static void
+down1 (int i)
+{
+ char buf[10 * i];
+
+ if (i > 0)
+ {
+ use_buffer (buf, 10 * i);
+ down1 (i - 1);
+ }
+}
+
+/* Same thing, using alloca. */
+
+static void
+down2 (int i)
+{
+ char *buf = alloca (10 * i);
+
+ if (i > 0)
+ {
+ use_buffer (buf, 10 * i);
+ down2 (i - 1);
+ }
+}
+
+int
+main (void)
+{
+ struct rlimit r;
+
+ /* We set a stack limit because we are usually invoked via make, and
+ make sets the stack limit to be as large as possible. */
+ r.rlim_cur = 8192 * 1024;
+ r.rlim_max = 8192 * 1024;
+ if (setrlimit (RLIMIT_STACK, &r) != 0)
+ abort ();
+ down1 (1000);
+ down2 (1000);
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/pr85388-5.c b/gcc/testsuite/gcc.dg/pr85388-5.c
new file mode 100644
index 00000000000..7462a40892c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr85388-5.c
@@ -0,0 +1,54 @@
+/* { dg-do run { target { i?86-*-linux* i?86-*-gnu* x86_64-*-linux* } } } */
+/* { dg-require-effective-target cet } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-options "-fsplit-stack -fcf-protection -mcet" } */
+
+/* This test is like split-3.c, but tests with a smaller stack frame,
+ since that uses a different prologue. */
+
+#include <stdarg.h>
+#include <stdlib.h>
+
+/* Use a noinline function to ensure that the buffer is not removed
+ from the stack. */
+static void use_buffer (char *buf) __attribute__ ((noinline));
+static void
+use_buffer (char *buf)
+{
+ buf[0] = '\0';
+}
+
+/* When using gold, the call to abort will force a stack split. */
+
+static void
+down (int i, ...)
+{
+ char buf[1];
+ va_list ap;
+
+ va_start (ap, i);
+ if (va_arg (ap, int) != 1
+ || va_arg (ap, int) != 2
+ || va_arg (ap, int) != 3
+ || va_arg (ap, int) != 4
+ || va_arg (ap, int) != 5
+ || va_arg (ap, int) != 6
+ || va_arg (ap, int) != 7
+ || va_arg (ap, int) != 8
+ || va_arg (ap, int) != 9
+ || va_arg (ap, int) != 10)
+ abort ();
+
+ if (i > 0)
+ {
+ use_buffer (buf);
+ down (i - 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+ }
+}
+
+int
+main (void)
+{
+ down (1000, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/pr85388-6.c b/gcc/testsuite/gcc.dg/pr85388-6.c
new file mode 100644
index 00000000000..23b5d8e3df6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr85388-6.c
@@ -0,0 +1,56 @@
+/* { dg-do run { target { i?86-*-linux* i?86-*-gnu* x86_64-*-linux* } } } */
+/* { dg-require-effective-target cet } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-options "-fsplit-stack -O2 -fcf-protection -mcet" } */
+/* { dg-options "-fsplit-stack -O2 -mno-accumulate-outgoing-args -fcf-protection -mcet" { target { { i?86-*-* x86_64-*-* } && ia32 } } } */
+
+/* A case that used to fail on 32-bit x86 when optimizing and not
+ using -maccumulate-args. The stack adjustment of the alloca got
+ mixed up with the arguments pushed on the stack to the function
+ before the call of alloca. */
+
+#include <stdlib.h>
+
+typedef struct { const char* s; int l; } s;
+
+typedef unsigned long long align16 __attribute__ ((aligned(16)));
+
+s gobats (const void *, int) __attribute__ ((noinline));
+
+s
+gobats (const void* p __attribute__ ((unused)),
+ int l __attribute__ ((unused)))
+{
+ s v;
+ v.s = 0;
+ v.l = 0;
+ return v;
+}
+
+void check_aligned (void *p) __attribute__ ((noinline));
+
+void
+check_aligned (void *p)
+{
+ if (((__SIZE_TYPE__) p & 0xf) != 0)
+ abort ();
+}
+
+void gap (void *) __attribute__ ((noinline));
+
+void gap (void *p)
+{
+ align16 a;
+ check_aligned (&a);
+}
+
+int
+main (int argc, char **argv)
+{
+ s *space;
+ gobats(0, 16);
+ space = (s *) alloca(sizeof(s) + 1);
+ *space = (s){0, 16};
+ gap(space);
+ return 0;
+}
--
2.14.3