elf: Expose ELF header on arch_setup_additional_pages()

Like it is done for SET_PERSONALITY with ARM, which requires the ELF
header to select correct personality parameters, x86 requires the
headers when selecting which VDSO to load, instead of relying on the
going-away TIF_IA32/X32 flags.

Add an indirection macro to arch_setup_additional_pages(), that x86 can
reimplement to receive the extra parameter just for ELF files.  This
requires no changes to other architectures, who can continue to use the
original arch_setup_additional_pages for ELF and non-ELF binaries.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201004032536.1229030-8-krisman@collabora.com

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index b23f755..aabc11f 100644 (file)
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1246,7 +1246,7 @@ out_free_interp:
        set_binfmt(&elf_format);
 
 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
-       retval = arch_setup_additional_pages(bprm, !!interpreter);
+       retval = ARCH_SETUP_ADDITIONAL_PAGES(bprm, elf_ex, !!interpreter);
        if (retval < 0)
                goto out;
 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */

diff --git a/fs/compat_binfmt_elf.c b/fs/compat_binfmt_elf.c
index 12b9913..2c55722 100644 (file)
--- a/fs/compat_binfmt_elf.c
+++ b/fs/compat_binfmt_elf.c
@@ -115,11 +115,16 @@
 #define START_THREAD           COMPAT_START_THREAD
 #endif
 
-#ifdef compat_arch_setup_additional_pages
+#ifdef compat_arch_setup_additional_pages
+#define COMPAT_ARCH_SETUP_ADDITIONAL_PAGES(bprm, ex, interpreter) \
+       compat_arch_setup_additional_pages(bprm, interpreter)
+#endif
+
+#ifdef COMPAT_ARCH_SETUP_ADDITIONAL_PAGES
 #undef ARCH_HAS_SETUP_ADDITIONAL_PAGES
 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
-#undef arch_setup_additional_pages
-#define        arch_setup_additional_pages compat_arch_setup_additional_pages
+#undef ARCH_SETUP_ADDITIONAL_PAGES
+#define        ARCH_SETUP_ADDITIONAL_PAGES COMPAT_ARCH_SETUP_ADDITIONAL_PAGES
 #endif
 
 #ifdef compat_elf_read_implies_exec

diff --git a/include/linux/elf.h b/include/linux/elf.h
index 6dbcfe7..c9a46c4 100644 (file)
--- a/include/linux/elf.h
+++ b/include/linux/elf.h
@@ -27,6 +27,11 @@
        start_thread(regs, elf_entry, start_stack)
 #endif
 
+#if defined(ARCH_HAS_SETUP_ADDITIONAL_PAGES) && !defined(ARCH_SETUP_ADDITIONAL_PAGES)
+#define ARCH_SETUP_ADDITIONAL_PAGES(bprm, ex, interpreter) \
+       arch_setup_additional_pages(bprm, interpreter)
+#endif
+
 #define ELF32_GNU_PROPERTY_ALIGN       4
 #define ELF64_GNU_PROPERTY_ALIGN       8