[glibc/fw/assert-cleanup] stdio: Clean up __libc_message after unconditional abort

[glibc/fw/assert-cleanup] stdio: Clean up __libc_message after unconditional abort

[Florian Weimer]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=cca9684f2d7a74fc0b28bfb1859955e0e28d7b4b

commit cca9684f2d7a74fc0b28bfb1859955e0e28d7b4b
Author: Florian Weimer <fweimer@redhat.com>
Date:   Wed Aug 3 11:41:53 2022 +0200

    stdio: Clean up __libc_message after unconditional abort
    
    Since commit ec2c1fcefb200c6cb7e09553f3c6af8815013d83 ("malloc:
    Abort on heap corruption, without a backtrace [BZ #21754]"),
    __libc_message always terminates the process.  Since commit
    a289ea09ea843ced6e5277c2f2e63c357bc7f9a3 ("Do not print backtraces
    on fatal glibc errors"), the backtrace facility has been removed.
    Therefore, remove enum __libc_message_action and the action
    argument of __libc_message, and mark __libc_message as _No_return.
    
    Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Diff:
---
 debug/fortify_fail.c       |  4 +---
 include/stdio.h            |  9 +--------
 malloc/malloc.c            |  5 ++---
 sysdeps/posix/libc_fatal.c | 47 +++++++++++++++++++++-------------------------
 4 files changed, 25 insertions(+), 40 deletions(-)

diff --git a/debug/fortify_fail.c b/debug/fortify_fail.c
index b1c51662b7..b880f82cb6 100644
--- a/debug/fortify_fail.c
+++ b/debug/fortify_fail.c
@@ -21,8 +21,6 @@ void
 __attribute__ ((noreturn))
 __fortify_fail (const char *msg)
 {
-  /* The loop is added only to keep gcc happy.  */
-  while (1)
-    __libc_message (do_abort, "*** %s ***: terminated\n", msg);
+  __libc_message ("*** %s ***: terminated\n", msg);
 }
 libc_hidden_def (__fortify_fail)
diff --git a/include/stdio.h b/include/stdio.h
index a6f7fd43cb..c3e772ad9a 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -143,18 +143,11 @@ extern int __gen_tempname (char *__tmpl, int __suffixlen, int __flags,
 #  define __GT_DIR	1	/* create a directory */
 #  define __GT_NOCREATE	2	/* just find a name not currently in use */
 
-enum __libc_message_action
-{
-  do_message	= 0,		/* Print message.  */
-  do_abort	= 1 << 0,	/* Abort.  */
-};
-
 /* Print out MESSAGE (which should end with a newline) on the error output
    and abort.  */
 extern void __libc_fatal (const char *__message)
      __attribute__ ((__noreturn__));
-extern void __libc_message (enum __libc_message_action action,
-			    const char *__fnt, ...) attribute_hidden;
+_Noreturn void __libc_message (const char *__fnt, ...) attribute_hidden;
 extern void __fortify_fail (const char *msg) __attribute__ ((__noreturn__));
 libc_hidden_proto (__fortify_fail)
 
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 430d204156..b2017c8fa7 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -297,8 +297,7 @@ _Noreturn static void
 __malloc_assert (const char *assertion, const char *file, unsigned int line,
 		 const char *function)
 {
-  __libc_message (do_abort, "\
-Fatal glibc error: malloc assertion failure in %s: %s\n",
+  __libc_message ("Fatal glibc error: malloc assertion failure in %s: %s\n",
 		  function, assertion);
   __builtin_unreachable ();
 }
@@ -5658,7 +5657,7 @@ static void
 malloc_printerr (const char *str)
 {
 #if IS_IN (libc)
-  __libc_message (do_abort, "%s\n", str);
+  __libc_message ("%s\n", str);
 #else
   __libc_fatal (str);
 #endif
diff --git a/sysdeps/posix/libc_fatal.c b/sysdeps/posix/libc_fatal.c
index 2ee0010b8d..270238495d 100644
--- a/sysdeps/posix/libc_fatal.c
+++ b/sysdeps/posix/libc_fatal.c
@@ -54,7 +54,7 @@ struct str_list
 
 /* Abort with an error message.  */
 void
-__libc_message (enum __libc_message_action action, const char *fmt, ...)
+__libc_message (const char *fmt, ...)
 {
   va_list ap;
   int fd = -1;
@@ -123,36 +123,31 @@ __libc_message (enum __libc_message_action action, const char *fmt, ...)
 
       WRITEV_FOR_FATAL (fd, iov, nlist, total);
 
-      if ((action & do_abort))
+      total = (total + 1 + GLRO(dl_pagesize) - 1) & ~(GLRO(dl_pagesize) - 1);
+      struct abort_msg_s *buf = __mmap (NULL, total,
+					PROT_READ | PROT_WRITE,
+					MAP_ANON | MAP_PRIVATE, -1, 0);
+      if (__glibc_likely (buf != MAP_FAILED))
 	{
-	  total = ((total + 1 + GLRO(dl_pagesize) - 1)
-		   & ~(GLRO(dl_pagesize) - 1));
-	  struct abort_msg_s *buf = __mmap (NULL, total,
-					    PROT_READ | PROT_WRITE,
-					    MAP_ANON | MAP_PRIVATE, -1, 0);
-	  if (__glibc_likely (buf != MAP_FAILED))
-	    {
-	      buf->size = total;
-	      char *wp = buf->msg;
-	      for (int cnt = 0; cnt < nlist; ++cnt)
-		wp = mempcpy (wp, iov[cnt].iov_base, iov[cnt].iov_len);
-	      *wp = '\0';
-
-	      /* We have to free the old buffer since the application might
-		 catch the SIGABRT signal.  */
-	      struct abort_msg_s *old = atomic_exchange_acq (&__abort_msg,
-							     buf);
-	      if (old != NULL)
-		__munmap (old, old->size);
-	    }
+	  buf->size = total;
+	  char *wp = buf->msg;
+	  for (int cnt = 0; cnt < nlist; ++cnt)
+	    wp = mempcpy (wp, iov[cnt].iov_base, iov[cnt].iov_len);
+	  *wp = '\0';
+
+	  /* We have to free the old buffer since the application might
+	     catch the SIGABRT signal.  */
+	  struct abort_msg_s *old = atomic_exchange_acq (&__abort_msg,
+							 buf);
+	  if (old != NULL)
+	    __munmap (old, old->size);
 	}
     }
 
   va_end (ap);
 
-  if ((action & do_abort))
-    /* Kill the application.  */
-    abort ();
+  /* Kill the application.  */
+  abort ();
 }
 
 
@@ -161,6 +156,6 @@ __libc_fatal (const char *message)
 {
   /* The loop is added only to keep gcc happy.  */
   while (1)
-    __libc_message (do_abort, "%s", message);
+    __libc_message ("%s", message);
 }
 libc_hidden_def (__libc_fatal)