diff mbox series

[v2] Add a setjmp/longjmp test between user contexts

Message ID ZYMJkpc7566ABU3W@gmail.com
State New
Headers show
Series [v2] Add a setjmp/longjmp test between user contexts | expand

Commit Message

H.J. Lu Dec. 20, 2023, 3:34 p.m. UTC
Changes in v2:

1. Change do_test to exit(EXIT_FAILURE).

H.J.
---
Verify that setjmp and longjmp work correctly between user contexts.
Arrange stacks for uctx_func1 and uctx_func2 so that ____longjmp_chk
works when setjmp and longjmp are called from different user contexts.
---
 stdlib/Makefile           |   1 +
 stdlib/tst-swapcontext2.c | 138 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 139 insertions(+)
 create mode 100644 stdlib/tst-swapcontext2.c

Comments

H.J. Lu Jan. 1, 2024, 2:14 p.m. UTC | #1
On Wed, Dec 20, 2023 at 7:34 AM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> Changes in v2:
>
> 1. Change do_test to exit(EXIT_FAILURE).
>
> H.J.
> ---
> Verify that setjmp and longjmp work correctly between user contexts.
> Arrange stacks for uctx_func1 and uctx_func2 so that ____longjmp_chk
> works when setjmp and longjmp are called from different user contexts.
> ---
>  stdlib/Makefile           |   1 +
>  stdlib/tst-swapcontext2.c | 138 ++++++++++++++++++++++++++++++++++++++
>  2 files changed, 139 insertions(+)
>  create mode 100644 stdlib/tst-swapcontext2.c
>
> diff --git a/stdlib/Makefile b/stdlib/Makefile
> index 0b5ef699a2..3cd05d184e 100644
> --- a/stdlib/Makefile
> +++ b/stdlib/Makefile
> @@ -256,6 +256,7 @@ tests := \
>    tst-strtol-locale \
>    tst-strtoll \
>    tst-swapcontext1 \
> +  tst-swapcontext2 \
>    tst-thread-quick_exit \
>    tst-tininess \
>    tst-unsetenv1 \
> diff --git a/stdlib/tst-swapcontext2.c b/stdlib/tst-swapcontext2.c
> new file mode 100644
> index 0000000000..f679755649
> --- /dev/null
> +++ b/stdlib/tst-swapcontext2.c
> @@ -0,0 +1,138 @@
> +/* Check setjmp/longjmp between user contexts.
> +   Copyright (C) 2023 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <setjmp.h>
> +#include <ucontext.h>
> +#include <stackinfo.h>
> +
> +static ucontext_t uctx_main, uctx_func1, uctx_func2;
> +const char *str1 = "\e[31mswapcontext(&uctx_func1, &uctx_main)\e[0m";
> +const char *str2 = "\e[34mswapcontext(&uctx_func2, &uctx_main)\e[0m";
> +const char *fmt1 = "\e[31m";
> +const char *fmt2 = "\e[34m";
> +static jmp_buf jmpbuf;
> +
> +#define handle_error(msg) \
> +  do { perror(msg); exit(EXIT_FAILURE); } while (0)
> +
> +__attribute__((noinline, noclone))
> +static void
> +func4(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
> +{
> +  printf("      %sfunc4: %s\e[0m\n", fmt, str);
> +  if (swapcontext(uocp, ucp) == -1)
> +    handle_error("swapcontext");
> +  printf("      %sfunc4: returning\e[0m\n", fmt);
> +}
> +
> +__attribute__((noinline, noclone))
> +static void
> +func3(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
> +{
> +  printf("    %sfunc3: func4(uocp, ucp, str)\e[0m\n", fmt);
> +  func4(uocp, ucp, str, fmt);
> +  printf("    %sfunc3: returning\e[0m\n", fmt);
> +}
> +
> +__attribute__((noinline, noclone))
> +static void
> +func1(void)
> +{
> +  while ( 1 )
> +    {
> +      printf("  \e[31mfunc1: func3(&uctx_func1, &uctx_main, str1)\e[0m\n");
> +      if (setjmp (jmpbuf) != 0)
> +       {
> +         printf("    %sfunc1: from longjmp\e[0m\n", fmt1);
> +         exit (EXIT_SUCCESS);
> +       }
> +      func3( &uctx_func1, &uctx_main, str1, fmt1);
> +    }
> +}
> +
> +__attribute__((noinline, noclone))
> +static void
> +func2(void)
> +{
> +  while ( 1 )
> +    {
> +      printf("  \e[34mfunc2: func3(&uctx_func2, &uctx_main, str2)\e[0m\n");
> +      func3(&uctx_func2, &uctx_main, str2, fmt2);
> +      printf("    %sfunc2: calling longjmp\e[0m\n", fmt2);
> +      longjmp (jmpbuf, 1);
> +    }
> +}
> +
> +static int
> +do_test (void)
> +{
> +  /* ____longjmp_chk has  */
> +#if 0
> +#ifdef _STACK_GROWS_DOWN
> +#define called_from(this, saved) ((this) < (saved))
> +#else
> +#define called_from(this, saved) ((this) > (saved))
> +#endif
> +
> + /* If "env" is from a frame that called us, we're all set.  */
> +  if (called_from(this_frame, saved_frame))
> +    __longjmp (env, val);
> +#endif
> +  /* Arrange stacks for uctx_func1 and uctx_func2 so that called_from
> +     is true when setjmp is called from uctx_func1 and longjmp is called
> +     from uctx_func2.  */
> +#ifdef _STACK_GROWS_DOWN
> +# define UCTX_FUNC1_STACK      1
> +# define UCTX_FUNC2_STACK      0
> +#else
> +# define UCTX_FUNC1_STACK      0
> +# define UCTX_FUNC2_STACK      1
> +#endif
> +  char func_stack[2][16384];
> +  int i;
> +
> +  if (getcontext(&uctx_func1) == -1)
> +    handle_error("getcontext");
> +  uctx_func1.uc_stack.ss_sp = func_stack[UCTX_FUNC1_STACK];
> +  uctx_func1.uc_stack.ss_size = sizeof (func_stack[UCTX_FUNC1_STACK]);
> +  uctx_func1.uc_link = &uctx_main;
> +  makecontext(&uctx_func1, func1, 0);
> +
> +  if (getcontext(&uctx_func2) == -1)
> +    handle_error("getcontext");
> +  uctx_func2.uc_stack.ss_sp = func_stack[UCTX_FUNC2_STACK];
> +  uctx_func2.uc_stack.ss_size = sizeof (func_stack[UCTX_FUNC2_STACK]);
> +  uctx_func2.uc_link = &uctx_func1;
> +  makecontext(&uctx_func2, func2, 0);
> +
> +  for ( i = 0; i < 2; i++ )
> +    {
> +      if (swapcontext(&uctx_main, &uctx_func1) == -1)
> +       handle_error("swapcontext");
> +      printf("        \e[35mmain: swapcontext(&uctx_main, &uctx_func2)\n\e[0m");
> +      if (swapcontext(&uctx_main, &uctx_func2) == -1)
> +       handle_error("swapcontext");
> +      printf("        \e[35mmain: swapcontext(&uctx_main, &uctx_func1)\n\e[0m");
> +    }
> +
> +  exit(EXIT_FAILURE);
> +}
> +
> +#include <support/test-driver.c>
> --
> 2.43.0
>

PING.
Noah Goldstein Jan. 1, 2024, 6:36 p.m. UTC | #2
On Mon, Jan 1, 2024 at 6:15 AM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Wed, Dec 20, 2023 at 7:34 AM H.J. Lu <hjl.tools@gmail.com> wrote:
> >
> > Changes in v2:
> >
> > 1. Change do_test to exit(EXIT_FAILURE).
> >
> > H.J.
> > ---
> > Verify that setjmp and longjmp work correctly between user contexts.
> > Arrange stacks for uctx_func1 and uctx_func2 so that ____longjmp_chk
> > works when setjmp and longjmp are called from different user contexts.
> > ---
> >  stdlib/Makefile           |   1 +
> >  stdlib/tst-swapcontext2.c | 138 ++++++++++++++++++++++++++++++++++++++
> >  2 files changed, 139 insertions(+)
> >  create mode 100644 stdlib/tst-swapcontext2.c
> >
> > diff --git a/stdlib/Makefile b/stdlib/Makefile
> > index 0b5ef699a2..3cd05d184e 100644
> > --- a/stdlib/Makefile
> > +++ b/stdlib/Makefile
> > @@ -256,6 +256,7 @@ tests := \
> >    tst-strtol-locale \
> >    tst-strtoll \
> >    tst-swapcontext1 \
> > +  tst-swapcontext2 \
> >    tst-thread-quick_exit \
> >    tst-tininess \
> >    tst-unsetenv1 \
> > diff --git a/stdlib/tst-swapcontext2.c b/stdlib/tst-swapcontext2.c
> > new file mode 100644
> > index 0000000000..f679755649
> > --- /dev/null
> > +++ b/stdlib/tst-swapcontext2.c
> > @@ -0,0 +1,138 @@
> > +/* Check setjmp/longjmp between user contexts.
> > +   Copyright (C) 2023 Free Software Foundation, Inc.
> > +   This file is part of the GNU C Library.
> > +
> > +   The GNU C Library is free software; you can redistribute it and/or
> > +   modify it under the terms of the GNU Lesser General Public
> > +   License as published by the Free Software Foundation; either
> > +   version 2.1 of the License, or (at your option) any later version.
> > +
> > +   The GNU C Library is distributed in the hope that it will be useful,
> > +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> > +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > +   Lesser General Public License for more details.
> > +
> > +   You should have received a copy of the GNU Lesser General Public
> > +   License along with the GNU C Library; if not, see
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +#include <stdio.h>
> > +#include <stdlib.h>
> > +#include <setjmp.h>
> > +#include <ucontext.h>
> > +#include <stackinfo.h>
> > +
> > +static ucontext_t uctx_main, uctx_func1, uctx_func2;
> > +const char *str1 = "\e[31mswapcontext(&uctx_func1, &uctx_main)\e[0m";
> > +const char *str2 = "\e[34mswapcontext(&uctx_func2, &uctx_main)\e[0m";
> > +const char *fmt1 = "\e[31m";
> > +const char *fmt2 = "\e[34m";
> > +static jmp_buf jmpbuf;
> > +
> > +#define handle_error(msg) \
> > +  do { perror(msg); exit(EXIT_FAILURE); } while (0)
> > +
> > +__attribute__((noinline, noclone))
> > +static void
> > +func4(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
> > +{
> > +  printf("      %sfunc4: %s\e[0m\n", fmt, str);
> > +  if (swapcontext(uocp, ucp) == -1)
> > +    handle_error("swapcontext");
> > +  printf("      %sfunc4: returning\e[0m\n", fmt);
> > +}
> > +
> > +__attribute__((noinline, noclone))
> > +static void
> > +func3(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
> > +{
> > +  printf("    %sfunc3: func4(uocp, ucp, str)\e[0m\n", fmt);
> > +  func4(uocp, ucp, str, fmt);
> > +  printf("    %sfunc3: returning\e[0m\n", fmt);
> > +}
> > +
> > +__attribute__((noinline, noclone))
> > +static void
> > +func1(void)
> > +{
> > +  while ( 1 )
> > +    {
> > +      printf("  \e[31mfunc1: func3(&uctx_func1, &uctx_main, str1)\e[0m\n");
> > +      if (setjmp (jmpbuf) != 0)
> > +       {
> > +         printf("    %sfunc1: from longjmp\e[0m\n", fmt1);
> > +         exit (EXIT_SUCCESS);
> > +       }
> > +      func3( &uctx_func1, &uctx_main, str1, fmt1);
> > +    }
> > +}
> > +
> > +__attribute__((noinline, noclone))
> > +static void
> > +func2(void)
> > +{
> > +  while ( 1 )
> > +    {
> > +      printf("  \e[34mfunc2: func3(&uctx_func2, &uctx_main, str2)\e[0m\n");
> > +      func3(&uctx_func2, &uctx_main, str2, fmt2);
> > +      printf("    %sfunc2: calling longjmp\e[0m\n", fmt2);
> > +      longjmp (jmpbuf, 1);
> > +    }
> > +}
> > +
> > +static int
> > +do_test (void)
> > +{
> > +  /* ____longjmp_chk has  */
> > +#if 0
> > +#ifdef _STACK_GROWS_DOWN
> > +#define called_from(this, saved) ((this) < (saved))
> > +#else
> > +#define called_from(this, saved) ((this) > (saved))
> > +#endif
> > +
> > + /* If "env" is from a frame that called us, we're all set.  */
> > +  if (called_from(this_frame, saved_frame))
> > +    __longjmp (env, val);
> > +#endif
> > +  /* Arrange stacks for uctx_func1 and uctx_func2 so that called_from
> > +     is true when setjmp is called from uctx_func1 and longjmp is called
> > +     from uctx_func2.  */
> > +#ifdef _STACK_GROWS_DOWN
> > +# define UCTX_FUNC1_STACK      1
> > +# define UCTX_FUNC2_STACK      0
> > +#else
> > +# define UCTX_FUNC1_STACK      0
> > +# define UCTX_FUNC2_STACK      1
> > +#endif
> > +  char func_stack[2][16384];
> > +  int i;
> > +
> > +  if (getcontext(&uctx_func1) == -1)
> > +    handle_error("getcontext");
> > +  uctx_func1.uc_stack.ss_sp = func_stack[UCTX_FUNC1_STACK];
> > +  uctx_func1.uc_stack.ss_size = sizeof (func_stack[UCTX_FUNC1_STACK]);
> > +  uctx_func1.uc_link = &uctx_main;
> > +  makecontext(&uctx_func1, func1, 0);
> > +
> > +  if (getcontext(&uctx_func2) == -1)
> > +    handle_error("getcontext");
> > +  uctx_func2.uc_stack.ss_sp = func_stack[UCTX_FUNC2_STACK];
> > +  uctx_func2.uc_stack.ss_size = sizeof (func_stack[UCTX_FUNC2_STACK]);
> > +  uctx_func2.uc_link = &uctx_func1;
> > +  makecontext(&uctx_func2, func2, 0);
> > +
> > +  for ( i = 0; i < 2; i++ )
> > +    {
> > +      if (swapcontext(&uctx_main, &uctx_func1) == -1)
> > +       handle_error("swapcontext");
> > +      printf("        \e[35mmain: swapcontext(&uctx_main, &uctx_func2)\n\e[0m");
> > +      if (swapcontext(&uctx_main, &uctx_func2) == -1)
> > +       handle_error("swapcontext");
> > +      printf("        \e[35mmain: swapcontext(&uctx_main, &uctx_func1)\n\e[0m");
> > +    }
> > +
> > +  exit(EXIT_FAILURE);
> > +}
> > +
> > +#include <support/test-driver.c>
> > --
> > 2.43.0
> >
>
> PING.
>
> --
> H.J.

LGTM.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
diff mbox series

Patch

diff --git a/stdlib/Makefile b/stdlib/Makefile
index 0b5ef699a2..3cd05d184e 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -256,6 +256,7 @@  tests := \
   tst-strtol-locale \
   tst-strtoll \
   tst-swapcontext1 \
+  tst-swapcontext2 \
   tst-thread-quick_exit \
   tst-tininess \
   tst-unsetenv1 \
diff --git a/stdlib/tst-swapcontext2.c b/stdlib/tst-swapcontext2.c
new file mode 100644
index 0000000000..f679755649
--- /dev/null
+++ b/stdlib/tst-swapcontext2.c
@@ -0,0 +1,138 @@ 
+/* Check setjmp/longjmp between user contexts.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <setjmp.h>
+#include <ucontext.h>
+#include <stackinfo.h>
+
+static ucontext_t uctx_main, uctx_func1, uctx_func2;
+const char *str1 = "\e[31mswapcontext(&uctx_func1, &uctx_main)\e[0m";
+const char *str2 = "\e[34mswapcontext(&uctx_func2, &uctx_main)\e[0m";
+const char *fmt1 = "\e[31m";
+const char *fmt2 = "\e[34m";
+static jmp_buf jmpbuf;
+
+#define handle_error(msg) \
+  do { perror(msg); exit(EXIT_FAILURE); } while (0)
+
+__attribute__((noinline, noclone))
+static void
+func4(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
+{
+  printf("      %sfunc4: %s\e[0m\n", fmt, str);
+  if (swapcontext(uocp, ucp) == -1)
+    handle_error("swapcontext");
+  printf("      %sfunc4: returning\e[0m\n", fmt);
+}
+
+__attribute__((noinline, noclone))
+static void
+func3(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
+{
+  printf("    %sfunc3: func4(uocp, ucp, str)\e[0m\n", fmt);
+  func4(uocp, ucp, str, fmt);
+  printf("    %sfunc3: returning\e[0m\n", fmt);
+}
+
+__attribute__((noinline, noclone))
+static void
+func1(void)
+{
+  while ( 1 )
+    {
+      printf("  \e[31mfunc1: func3(&uctx_func1, &uctx_main, str1)\e[0m\n");
+      if (setjmp (jmpbuf) != 0)
+	{
+	  printf("    %sfunc1: from longjmp\e[0m\n", fmt1);
+	  exit (EXIT_SUCCESS);
+	}
+      func3( &uctx_func1, &uctx_main, str1, fmt1);
+    }
+}
+
+__attribute__((noinline, noclone))
+static void
+func2(void)
+{
+  while ( 1 )
+    {
+      printf("  \e[34mfunc2: func3(&uctx_func2, &uctx_main, str2)\e[0m\n");
+      func3(&uctx_func2, &uctx_main, str2, fmt2);
+      printf("    %sfunc2: calling longjmp\e[0m\n", fmt2);
+      longjmp (jmpbuf, 1);
+    }
+}
+
+static int
+do_test (void)
+{
+  /* ____longjmp_chk has  */
+#if 0
+#ifdef _STACK_GROWS_DOWN
+#define called_from(this, saved) ((this) < (saved))
+#else
+#define called_from(this, saved) ((this) > (saved))
+#endif
+
+ /* If "env" is from a frame that called us, we're all set.  */
+  if (called_from(this_frame, saved_frame))
+    __longjmp (env, val);
+#endif
+  /* Arrange stacks for uctx_func1 and uctx_func2 so that called_from
+     is true when setjmp is called from uctx_func1 and longjmp is called
+     from uctx_func2.  */
+#ifdef _STACK_GROWS_DOWN
+# define UCTX_FUNC1_STACK	1
+# define UCTX_FUNC2_STACK	0
+#else
+# define UCTX_FUNC1_STACK	0
+# define UCTX_FUNC2_STACK	1
+#endif
+  char func_stack[2][16384];
+  int i;
+
+  if (getcontext(&uctx_func1) == -1)
+    handle_error("getcontext");
+  uctx_func1.uc_stack.ss_sp = func_stack[UCTX_FUNC1_STACK];
+  uctx_func1.uc_stack.ss_size = sizeof (func_stack[UCTX_FUNC1_STACK]);
+  uctx_func1.uc_link = &uctx_main;
+  makecontext(&uctx_func1, func1, 0);
+
+  if (getcontext(&uctx_func2) == -1)
+    handle_error("getcontext");
+  uctx_func2.uc_stack.ss_sp = func_stack[UCTX_FUNC2_STACK];
+  uctx_func2.uc_stack.ss_size = sizeof (func_stack[UCTX_FUNC2_STACK]);
+  uctx_func2.uc_link = &uctx_func1;
+  makecontext(&uctx_func2, func2, 0);
+
+  for ( i = 0; i < 2; i++ )
+    {
+      if (swapcontext(&uctx_main, &uctx_func1) == -1)
+	handle_error("swapcontext");
+      printf("        \e[35mmain: swapcontext(&uctx_main, &uctx_func2)\n\e[0m");
+      if (swapcontext(&uctx_main, &uctx_func2) == -1)
+	handle_error("swapcontext");
+      printf("        \e[35mmain: swapcontext(&uctx_main, &uctx_func1)\n\e[0m");
+    }
+
+  exit(EXIT_FAILURE);
+}
+
+#include <support/test-driver.c>