aboutsummaryrefslogtreecommitdiff
path: root/arch/x86
diff options
context:
space:
mode:
authorBen Hutchings <ben@decadent.org.uk>2014-09-07 21:05:05 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-11-14 08:59:47 -0800
commitc8d171f62647794b4e7ab59b4fdd62e6b0e4cd42 (patch)
treebb63b7b59a02e175a9a159917069273003e6b57d /arch/x86
parentb1d9bf74d2ee549a0db336169a2cc02849dbf533 (diff)
x86: Reject x32 executables if x32 ABI not supported
commit 0e6d3112a4e95d55cf6dca88f298d5f4b8f29bd1 upstream. It is currently possible to execve() an x32 executable on an x86_64 kernel that has only ia32 compat enabled. However all its syscalls will fail, even _exit(). This usually causes it to segfault. Change the ELF compat architecture check so that x32 executables are rejected if we don't support the x32 ABI. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Link: http://lkml.kernel.org/r/1410120305.6822.9.camel@decadent.org.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/include/asm/elf.h5
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index 9c999c1674fa..01f15b227d7e 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -155,8 +155,9 @@ do { \
#define elf_check_arch(x) \
((x)->e_machine == EM_X86_64)
-#define compat_elf_check_arch(x) \
- (elf_check_arch_ia32(x) || (x)->e_machine == EM_X86_64)
+#define compat_elf_check_arch(x) \
+ (elf_check_arch_ia32(x) || \
+ (IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64))
#if __USER32_DS != __USER_DS
# error "The following code assumes __USER32_DS == __USER_DS"