This is the mail archive of the binutils-cvs@sourceware.org mailing list for the binutils project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[binutils-gdb] Issue an error for read-only segment with dynamic IFUNC relocations


https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=8efa2874ab298f3923f4127340da119435f87c39

commit 8efa2874ab298f3923f4127340da119435f87c39
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Thu Aug 13 04:31:38 2015 -0700

    Issue an error for read-only segment with dynamic IFUNC relocations
    
    To load an ELF binary with DT_TEXTREL tag, the dynamic linker calls
    __mprotect on the read-only segment with PROT_READ|PROT_WRITE before
    applying dynamic relocation.  It leads to segfault when performing
    IFUNC relocations since the read-only segment has no execute permission.
    This patch changes x86 linker to issue an error for read-only segment
    with dynamic IFUNC relocations.  Other backends with IFUNC support
    may need a similar change.
    
    bfd/
    
    	PR ld/18801
    	* elf32-i386.c (elf_i386_size_dynamic_sections): Issue an error
    	for read-only segment with dynamic IFUNC relocations.
    	* elf64-x86-64.c (elf_x86_64_size_dynamic_sections): Likewise.
    
    ld/testsuite/
    
    	PR ld/18801
    	* ld-i386/i386.exp: Run pr18801.
    	* ld-x86-64/x86-64.exp: Likewise.
    	* ld-i386/pr18801.d: New file.
    	* ld-i386/pr18801.s: Likewise.
    	* ld-x86-64/pr18801.d: Likewise.
    	* ld-x86-64/pr18801.s: Likewise.

Diff:
---
 bfd/ChangeLog                     |  7 +++++++
 bfd/elf32-i386.c                  |  9 +++++++++
 bfd/elf64-x86-64.c                |  9 +++++++++
 ld/testsuite/ChangeLog            | 10 ++++++++++
 ld/testsuite/ld-i386/i386.exp     |  1 +
 ld/testsuite/ld-i386/pr18801.d    |  3 +++
 ld/testsuite/ld-i386/pr18801.s    | 15 +++++++++++++++
 ld/testsuite/ld-x86-64/pr18801.d  |  3 +++
 ld/testsuite/ld-x86-64/pr18801.s  | 15 +++++++++++++++
 ld/testsuite/ld-x86-64/x86-64.exp |  1 +
 10 files changed, 73 insertions(+)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index e561764..9ba5902 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,10 @@
+2015-08-13  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/18801
+	* elf32-i386.c (elf_i386_size_dynamic_sections): Issue an error
+	for read-only segment with dynamic IFUNC relocations.
+	* elf64-x86-64.c (elf_x86_64_size_dynamic_sections): Likewise.
+
 2015-08-12  Simon Dardis  <simon.dardis@imgtec.com>
 
 	* elfxx-mips.c (STUB_MOVE): Change to use 'or' only.
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index 3063bed..1e4c3f4 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -3152,6 +3152,15 @@ elf_i386_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
 
 	  if ((info->flags & DF_TEXTREL) != 0)
 	    {
+	      if ((elf_tdata (output_bfd)->has_gnu_symbols
+		   & elf_gnu_symbol_ifunc) == elf_gnu_symbol_ifunc)
+		{
+		  info->callbacks->einfo
+		    (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
+		  bfd_set_error (bfd_error_bad_value);
+		  return FALSE;
+		}
+
 	      if (!add_dynamic_entry (DT_TEXTREL, 0))
 		return FALSE;
 	    }
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index 2d3c55e..348b297 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -3513,6 +3513,15 @@ elf_x86_64_size_dynamic_sections (bfd *output_bfd,
 
 	  if ((info->flags & DF_TEXTREL) != 0)
 	    {
+	      if ((elf_tdata (output_bfd)->has_gnu_symbols
+		   & elf_gnu_symbol_ifunc) == elf_gnu_symbol_ifunc)
+		{
+		  info->callbacks->einfo
+		    (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
+		  bfd_set_error (bfd_error_bad_value);
+		  return FALSE;
+		}
+
 	      if (!add_dynamic_entry (DT_TEXTREL, 0))
 		return FALSE;
 	    }
diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog
index a38dc8b..5ae5cd4 100644
--- a/ld/testsuite/ChangeLog
+++ b/ld/testsuite/ChangeLog
@@ -1,3 +1,13 @@
+2015-08-13  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/18801
+	* ld-i386/i386.exp: Run pr18801.
+	* ld-x86-64/x86-64.exp: Likewise.
+	* ld-i386/pr18801.d: New file.
+	* ld-i386/pr18801.s: Likewise.
+	* ld-x86-64/pr18801.d: Likewise.
+	* ld-x86-64/pr18801.s: Likewise.
+
 2015-08-12  Simon Dardis  <simon.dardis@imgtec.com>
 
 	* ld-mips-elf/compressed-plt-1-n32-mips16.od: Update test.
diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index 0a718cf..47911a6 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -309,6 +309,7 @@ run_dump_test "pr14215"
 run_dump_test "pr17057"
 run_dump_test "pr17935-1"
 run_dump_test "pr17935-2"
+run_dump_test "pr18801"
 run_dump_test "pr18815"
 
 # Add $PLT_CFLAGS if PLT is expected.
diff --git a/ld/testsuite/ld-i386/pr18801.d b/ld/testsuite/ld-i386/pr18801.d
new file mode 100644
index 0000000..4bb2efb
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr18801.d
@@ -0,0 +1,3 @@
+#as: --32
+#ld: -m elf_i386 -pie
+#error: read-only segment has dynamic IFUNC relocations; recompile with -fPIC
diff --git a/ld/testsuite/ld-i386/pr18801.s b/ld/testsuite/ld-i386/pr18801.s
new file mode 100644
index 0000000..ac3377d
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr18801.s
@@ -0,0 +1,15 @@
+	.text
+	.type   selector, %function
+foo:
+	movl	$0, %eax
+	ret
+selector:
+	mov	$foo, %eax
+	ret
+	.type   selector, %gnu_indirect_function
+	.globl	_start
+_start:
+	mov	$selector, %eax
+	call	*%eax
+	ret
+	.section	.note.GNU-stack,"",@progbits
diff --git a/ld/testsuite/ld-x86-64/pr18801.d b/ld/testsuite/ld-x86-64/pr18801.d
new file mode 100644
index 0000000..459db6b
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr18801.d
@@ -0,0 +1,3 @@
+#as: --64
+#ld: -melf_x86_64 -pie
+#error: read-only segment has dynamic IFUNC relocations; recompile with -fPIC
diff --git a/ld/testsuite/ld-x86-64/pr18801.s b/ld/testsuite/ld-x86-64/pr18801.s
new file mode 100644
index 0000000..16d36da
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr18801.s
@@ -0,0 +1,15 @@
+	.text
+	.type   selector, %function
+foo:
+	movl	$0, %eax
+	ret
+selector:
+	movabs	$foo, %rax
+	ret
+	.type   selector, %gnu_indirect_function
+	.globl	_start
+_start:
+	movabs	$selector, %rax
+	call	*%rax
+	ret
+	.section	.note.GNU-stack,"",@progbits
diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp
index bd48cd3..5409dff 100644
--- a/ld/testsuite/ld-x86-64/x86-64.exp
+++ b/ld/testsuite/ld-x86-64/x86-64.exp
@@ -325,6 +325,7 @@ run_dump_test "pr17935-1"
 run_dump_test "pr17935-2"
 run_dump_test "pr18160"
 run_dump_test "pr18176"
+run_dump_test "pr18801"
 run_dump_test "pr18815"
 
 # Add $PLT_CFLAGS if PLT is expected.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]