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-rw-r--r--ChangeLog10
-rw-r--r--elf/Makefile41
-rw-r--r--elf/check-execstack.c162
-rw-r--r--scripts/check-execstack.awk52
4 files changed, 88 insertions, 177 deletions
diff --git a/ChangeLog b/ChangeLog
index e4869248ae..91d6cbbfd6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
2012-05-01 Roland McGrath <roland@hack.frob.com>
+ * scripts/check-execstack.awk: New file.
+ * elf/Makefile ($(objpfx)check-execstack): Target removed.
+ (check-execstack-CFLAGS): Variable removed.
+ ($(objpfx)check-execstack.h): Target removed.
+ ($(objpfx)execstack-default): New target.
+ (generated): Add that instead of check-execstack.h.
+ ($(all-built-dso:=.phdr)): New static pattern rule.
+ (generated): Add those targets.
+ * elf/check-execstack.c: File removed.
+
* scripts/check-textrel.awk: New file.
* elf/Makefile ($(objpfx)check-textrel): Target removed.
(check-textrel-CFLAGS): Variable removed.
diff --git a/elf/Makefile b/elf/Makefile
index 50934be71b..c207b53904 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -872,18 +872,6 @@ CFLAGS-tst-pie1.c += $(pie-ccflag)
$(objpfx)tst-pie1: $(objpfx)tst-piemod1.so
-check-execstack-CFLAGS = -O -Wall -D_XOPEN_SOURCE=600 -D_BSD_SOURCE -std=gnu99 \
- $(objpfx:%/=-I%)
-$(objpfx)check-execstack: check-execstack.c $(objpfx)check-execstack.h
- $(native-compile)
-$(objpfx)check-execstack.h: $(first-word $(wildcard $(sysdirs:%=%/stackinfo.h)))
- $(make-target-directory)
- { echo '#include <stackinfo.h>'; echo '@@@DEFAULT_STACK_PERMS@@@'; } | \
- $(CC) $(CFLAGS) $(CPPFLAGS) -E -x c-header - | \
- sed -n -e 's/^@@@\(.*\)@@@/#define DEFAULT_STACK_PERMS \1/p' > $@T
- mv -f $@T $@
-generated += check-execstack.h
-
check-localplt-CFLAGS = -O -Wall -D_GNU_SOURCE -std=gnu99
$(objpfx)check-localplt: check-localplt.c
$(native-compile)
@@ -909,9 +897,32 @@ $(objpfx)check-textrel.out: $(..)scripts/check-textrel.awk \
LC_ALL=C $(AWK) -f $^ > $@
generated += check-textrel.out
-$(objpfx)check-execstack.out: $(objpfx)check-execstack $(all-built-dso)
- $(dir $<)$(notdir $<) $(filter-out $<, $^) > $@
-generated += check-execstack check-execstack.out
+$(objpfx)execstack-default: $(first-word $(wildcard $(sysdirs:%=%/stackinfo.h)))
+ $(make-target-directory)
+ { echo '#include <elf.h>'; \
+ echo '#include <stackinfo.h>'; \
+ echo '#if (DEFAULT_STACK_PERMS & PF_X) == 0'; \
+ echo '@@@execstack-no@@@'; \
+ echo '#else'; \
+ echo '@@@execstack-yes@@@'; \
+ echo '#endif'; } | \
+ $(CC) $(CFLAGS) $(CPPFLAGS) -E -x c-header - | \
+ sed -n -e 's/^@@@\(.*\)@@@/\1/p' > $@T
+ mv -f $@T $@
+generated += execstack-default
+
+$(all-built-dso:=.phdr): %.phdr: %
+ @rm -f $@T
+ LC_ALL=C $(READELF) -W -l $< > $@T
+ test -s $@T
+ mv -f $@T $@
+generated += $(all-built-dso:=.phdr)
+
+$(objpfx)check-execstack.out: $(..)scripts/check-execstack.awk \
+ $(objpfx)execstack-default \
+ $(all-built-dso:=.phdr)
+ LC_ALL=C $(AWK) -f $^ > $@
+generated += check-execstack.out
$(objpfx)tst-dlmodcount: $(libdl)
$(objpfx)tst-dlmodcount.out: $(test-modules)
diff --git a/elf/check-execstack.c b/elf/check-execstack.c
deleted file mode 100644
index 6a5c4d9b9a..0000000000
--- a/elf/check-execstack.c
+++ /dev/null
@@ -1,162 +0,0 @@
-/* Check for executable stacks in DSOs.
- Copyright (C) 2009, 2010 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contribute by Ulrich Drepper <drepper@redhat.com>. 2009.
-
- 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
- <http://www.gnu.org/licenses/>. */
-
-#include <byteswap.h>
-#include <elf.h>
-#include <endian.h>
-#include <fcntl.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include "check-execstack.h"
-
-
-#ifdef BITS
-
-# define AB(name) _AB (name, BITS)
-# define _AB(name, bits) __AB (name, bits)
-# define __AB(name, bits) name##bits
-# define E(name) _E (name, BITS)
-# define _E(name, bits) __E (name, bits)
-# define __E(name, bits) Elf##bits##_##name
-# define SWAP(val) \
- ({ __typeof (val) __res; \
- if (((ehdr.e_ident[EI_DATA] == ELFDATA2MSB \
- && BYTE_ORDER == LITTLE_ENDIAN) \
- || (ehdr.e_ident[EI_DATA] == ELFDATA2LSB \
- && BYTE_ORDER == BIG_ENDIAN)) \
- && sizeof (val) != 1) \
- { \
- if (sizeof (val) == 2) \
- __res = bswap_16 (val); \
- else if (sizeof (val) == 4) \
- __res = bswap_32 (val); \
- else \
- __res = bswap_64 (val); \
- } \
- else \
- __res = (val); \
- __res; })
-
-
-static int
-AB(handle_file) (const char *fname, int fd)
-{
- E(Ehdr) ehdr;
-
- if (pread (fd, &ehdr, sizeof (ehdr), 0) != sizeof (ehdr))
- {
- read_error:
- printf ("%s: read error: %m\n", fname);
- return 1;
- }
-
- const size_t phnum = SWAP (ehdr.e_phnum);
- const size_t phentsize = SWAP (ehdr.e_phentsize);
-
- /* Read the program header. */
- E(Phdr) *phdr = alloca (phentsize * phnum);
- if (pread (fd, phdr, phentsize * phnum, SWAP (ehdr.e_phoff))
- != phentsize * phnum)
- goto read_error;
-
- /* Search for the PT_GNU_STACK entry. */
- for (size_t cnt = 0; cnt < phnum; ++cnt)
- if (SWAP (phdr[cnt].p_type) == PT_GNU_STACK)
- {
- unsigned int flags = SWAP(phdr[cnt].p_flags);
- if (flags & PF_X)
- {
- printf ("%s: executable stack signaled\n", fname);
- return 1;
- }
-
- return 0;
- }
-
- if (DEFAULT_STACK_PERMS & PF_X)
- {
- printf ("%s: no PT_GNU_STACK entry\n", fname);
- return 1;
- }
-
- return 0;
-}
-
-# undef BITS
-#else
-
-# define BITS 32
-# include "check-execstack.c"
-
-# define BITS 64
-# include "check-execstack.c"
-
-
-static int
-handle_file (const char *fname)
-{
- int fd = open (fname, O_RDONLY);
- if (fd == -1)
- {
- printf ("cannot open %s: %m\n", fname);
- return 1;
- }
-
- /* Read was is supposed to be the ELF header. Read the initial
- bytes to determine whether this is a 32 or 64 bit file. */
- char ident[EI_NIDENT];
- if (read (fd, ident, EI_NIDENT) != EI_NIDENT)
- {
- printf ("%s: read error: %m\n", fname);
- close (fd);
- return 1;
- }
-
- if (memcmp (&ident[EI_MAG0], ELFMAG, SELFMAG) != 0)
- {
- printf ("%s: not an ELF file\n", fname);
- close (fd);
- return 1;
- }
-
- int result;
- if (ident[EI_CLASS] == ELFCLASS64)
- result = handle_file64 (fname, fd);
- else
- result = handle_file32 (fname, fd);
-
- close (fd);
-
- return result;
-}
-
-
-int
-main (int argc, char *argv[])
-{
- int cnt;
- int result = 0;
-
- for (cnt = 1; cnt < argc; ++cnt)
- result |= handle_file (argv[cnt]);
- return result;
-}
-#endif
diff --git a/scripts/check-execstack.awk b/scripts/check-execstack.awk
new file mode 100644
index 0000000000..21d37e9f47
--- /dev/null
+++ b/scripts/check-execstack.awk
@@ -0,0 +1,52 @@
+# This awk script expects to get command-line files that are each
+# the output of 'readelf -l' on a single shared object.
+# But the first file should contain just "execstack-no" or "execstack-yes",
+# indicating what the default is in the absence of PT_GNU_STACK.
+# It exits successfully (0) if none indicated executable stack.
+# It fails (1) if any did indicate executable stack.
+# It fails (2) if the input did not take the expected form.
+
+BEGIN { result = sanity = 0; default_exec = -1 }
+
+/^execstack-no$/ { default_exec = 0; next }
+/^execstack-yes$/ { default_exec = 1; next }
+
+function check_one(name) {
+ if (default_exec == -1) {
+ print "*** missing execstack-default file?";
+ result = 2;
+ }
+
+ if (!sanity) {
+ print name ": *** input did not look like readelf -l output";
+ result = 2;
+ } else if (stack_line) {
+ if (stack_line ~ /^.*RW .*$/) {
+ print name ": OK";
+ } else if (stack_line ~ /^.*E.*$/) {
+ print name ": *** executable stack signaled";
+ result = result ? result : 1;
+ }
+ } else if (default_exec) {
+ print name ": *** no PT_GNU_STACK entry";
+ result = result ? result : 1;
+ } else {
+ print name ": no PT_GNU_STACK but default is OK";
+ }
+
+ sanity = 0;
+}
+
+FILENAME != lastfile {
+ if (lastfile)
+ check_one(lastfile);
+ lastfile = FILENAME;
+}
+
+$1 == "Type" && $7 == "Flg" { sanity = 1; stack_line = "" }
+$1 == "GNU_STACK" { stack_line = $0 }
+
+END {
+ check_one(lastfile);
+ exit(result);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-21 19:35:46 +0000