automatic import of glibcopeneuler22.03_LTS_SP4openeuler22.03_LTS_SP3openeuler20.03

1 files changed, 90 insertions, 0 deletions

diff --git a/backport-elf-Remove-allocate-use-on-_dl_debug_printf.patch b/backport-elf-Remove-allocate-use-on-_dl_debug_printf.patch
new file mode 100644
index 0000000..28d68a6
--- /dev/null
+++ b/backport-elf-Remove-allocate-use-on-_dl_debug_printf.patch
@@ -0,0 +1,90 @@
+From 40c112ed0d7d0577d2f84851c1f7b8157b3bd2f5 Mon Sep 17 00:00:00 2001
+From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
+Date: Mon, 31 Oct 2022 15:46:38 -0300
+Subject: [PATCH] elf: Remove allocate use on _dl_debug_printf
+
+The maximum number of directives is already limited by the maximum
+value of iovec, and current padding usage on _dl_map_object_from_fd
+specifies a value of 16 (2 times sizeof (void *)) in hexa, which is
+less than the INT_STRLEN_BOUND(void *) (20 for LP64).
+
+This works if pointers are larger than 8 bytes, for instance 16.
+In this case the maximum padding would be 32 and the IFMTSIZE would
+be 40.
+
+The resulting code does use a slightly larger static stack, the
+output of -fstack-usage (for x86_64):
+
+ * master:
+   dl-printf.c:35:1:_dl_debug_vdprintf     1344    dynamic
+
+ * patch:
+   dl-printf.c:36:1:_dl_debug_vdprintf     2416    static
+
+However, there is an improvement in code generation:
+
+ * master
+   text    data     bss     dec     hex filename
+   330900    3309     ced elf/dl-printf.os
+
+ * patch
+text    data     bss     dec     hex filename
+315100    3151     c4f elf/dl-printf.os
+
+Checked on x86_64-linux-gnu.
+
+Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
+---
+ elf/dl-misc.c | 15 +++++++--------
+ 1 file changed, 7 insertions(+), 8 deletions(-)
+
+diff --git a/elf/dl-misc.c b/elf/dl-misc.c
+index a11d11d5..4a33737c 100644
+--- a/elf/dl-misc.c
++++ b/elf/dl-misc.c
+@@ -34,6 +34,7 @@
+ #include <_itoa.h>
+ #include <dl-writev.h>
+ #include <not-cancel.h>
++#include <intprops.h>
+ 
+ /* Read the whole contents of FILE into new mmap'd space with given
+    protections.  *SIZEP gets the size of the file.  On error MAP_FAILED
+@@ -79,6 +80,9 @@ _dl_debug_vdprintf (int fd, int tag_p, const char *fmt, va_list arg)
+ {
+ # define NIOVMAX 64
+   struct iovec iov[NIOVMAX];
++  /* Maximum size for 'd', 'u', and 'x' including padding.  */
++  enum { IFMTSIZE = INT_STRLEN_BOUND(void *) };
++  char ifmtbuf[NIOVMAX][IFMTSIZE];
+   int niov = 0;
+   pid_t pid = 0;
+   char pidbuf[12];
+@@ -143,6 +147,8 @@ _dl_debug_vdprintf (int fd, int tag_p, const char *fmt, va_list arg)
+ 	  if (*fmt == '*')
+ 	    {
+ 	      width = va_arg (arg, int);
++	      /* The maximum padding accepted is up to pointer size.  */
++	      assert (width < IFMTSIZE);
+ 	      ++fmt;
+ 	    }
+ 
+@@ -203,14 +209,7 @@ _dl_debug_vdprintf (int fd, int tag_p, const char *fmt, va_list arg)
+ #endif
+ 		  }
+ 
+-		/* We use alloca() to allocate the buffer with the most
+-		   pessimistic guess for the size.  Using alloca() allows
+-		   having more than one integer formatting in a call.  */
+-		int size = 1 + 3 * sizeof (unsigned long int);
+-		if (width + 1 > size)
+-		  size = width + 1;
+-		char *buf = (char *) alloca (size);
+-		char *endp = &buf[size];
++		char *endp = &ifmtbuf[niov][IFMTSIZE];
+ 		char *cp = _itoa (num, endp, *fmt == 'x' ? 16 : 10, 0);
+ 
+ 		/* Pad to the width the user specified.  */
+-- 
+2.33.0
+