[binutils-gdb] x86: Properly check invalid relocation against protected symbol

[H.J. Lu <hjl@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=bd0736124c20950ac353f01e5029b7cb5d8a7010

commit bd0736124c20950ac353f01e5029b7cb5d8a7010
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Mon Jul 18 11:44:32 2022 -0700

    x86: Properly check invalid relocation against protected symbol
    
    Only check invalid relocation against protected symbol defined in shared
    object.
    
    bfd/
    
            PR ld/29377
            * elf32-i386.c (elf_i386_scan_relocs): Only check invalid
            relocation against protected symbol defined in shared object.
            * elf64-x86-64.c (elf_x86_64_scan_relocs): Likewise.
    
    ld/
    
            PR ld/29377
            * testsuite/ld-elf/linux-x86.exp: Run PR ld/29377 tests.
            * testsuite/ld-elf/pr29377a.c: New file.
            * testsuite/ld-elf/pr29377b.c: Likewise.

Diff:
---
 bfd/elf32-i386.c                  |  2 ++
 bfd/elf64-x86-64.c                |  2 ++
 ld/testsuite/ld-elf/linux-x86.exp | 16 ++++++++++++++++
 ld/testsuite/ld-elf/pr29377a.c    |  5 +++++
 ld/testsuite/ld-elf/pr29377b.c    | 10 ++++++++++
 5 files changed, 35 insertions(+)

diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index e4106d9fd3b..3d39dc07fe0 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -1811,6 +1811,8 @@ elf_i386_scan_relocs (bfd *abfd,
 		  if (h->pointer_equality_needed
 		      && h->type == STT_FUNC
 		      && eh->def_protected
+		      && !SYMBOL_DEFINED_NON_SHARED_P (h)
+		      && h->def_dynamic
 		      && elf_has_indirect_extern_access (h->root.u.def.section->owner))
 		    {
 		      /* Disallow non-canonical reference to canonical
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index 6154a70bdd7..48ca6309d1b 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -2254,6 +2254,8 @@ elf_x86_64_scan_relocs (bfd *abfd, struct bfd_link_info *info,
 		  if (h->pointer_equality_needed
 		      && h->type == STT_FUNC
 		      && eh->def_protected
+		      && !SYMBOL_DEFINED_NON_SHARED_P (h)
+		      && h->def_dynamic
 		      && elf_has_indirect_extern_access (h->root.u.def.section->owner))
 		    {
 		      /* Disallow non-canonical reference to canonical
diff --git a/ld/testsuite/ld-elf/linux-x86.exp b/ld/testsuite/ld-elf/linux-x86.exp
index 6035ecd6829..0f0a6f01ec0 100644
--- a/ld/testsuite/ld-elf/linux-x86.exp
+++ b/ld/testsuite/ld-elf/linux-x86.exp
@@ -134,6 +134,22 @@ run_cc_link_tests [list \
 	{{readelf {--dyn-syms -W} pr28158.rd} {nm -D pr28158.nd}} \
 	"pr28158" \
     ] \
+    [list \
+	"Build pr29377.o" \
+	"-r -Wl,-z,noexecstack" \
+	"" \
+	{pr29377a.c indirect-extern-access.S} \
+	{} \
+	"pr29377.o" \
+    ] \
+    [list \
+	"Build pr29377" \
+	"$NOPIE_LDFLAGS tmpdir/pr29377.o" \
+	"-fPIC" \
+	{pr29377b.c} \
+	{} \
+	"pr29377" \
+    ] \
 ]
 
 run_ld_link_exec_tests [list \
diff --git a/ld/testsuite/ld-elf/pr29377a.c b/ld/testsuite/ld-elf/pr29377a.c
new file mode 100644
index 00000000000..41d9545e3bf
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr29377a.c
@@ -0,0 +1,5 @@
+__attribute__ ((visibility ("protected")))
+void
+foo (void)
+{
+}
diff --git a/ld/testsuite/ld-elf/pr29377b.c b/ld/testsuite/ld-elf/pr29377b.c
new file mode 100644
index 00000000000..3cf163b25b4
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr29377b.c
@@ -0,0 +1,10 @@
+extern void foo (void);
+
+void (*foo_p) (void);
+
+int
+main ()
+{
+  foo_p = foo;
+  return 0;
+}