x86: hook up execveat system call

Hook up x86-64, i386 and x32 ABIs.

Signed-off-by: David Drysdale <drysdale@google.com>
Cc: Meredydd Luff <meredydd@senatehouse.org>
Cc: Shuah Khan <shuah.kh@samsung.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rich Felker <dalias@aerifal.cx>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 29 insertions, 0 deletions

diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c
index 06d3e5a14d9d..f3672508b249 100644
--- a/arch/x86/kernel/audit_64.c
+++ b/arch/x86/kernel/audit_64.c
@@ -50,6 +50,7 @@ int audit_classify_syscall(int abi, unsigned syscall)
         case __NR_openat:
                 return 3;
         case __NR_execve:
+        case __NR_execveat:
                 return 5;
         default:
                 return 0;
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index c0226ab54106..90878aa38dbd 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -652,6 +652,20 @@ ENTRY(stub_execve)
         CFI_ENDPROC
 END(stub_execve)
 
+ENTRY(stub_execveat)
+        CFI_STARTPROC
+        addq $8, %rsp
+        PARTIAL_FRAME 0
+        SAVE_REST
+        FIXUP_TOP_OF_STACK %r11
+        call sys_execveat
+        RESTORE_TOP_OF_STACK %r11
+        movq %rax,RAX(%rsp)
+        RESTORE_REST
+        jmp int_ret_from_sys_call
+        CFI_ENDPROC
+END(stub_execveat)
+
 /*
  * sigreturn is special because it needs to restore all registers on return.
  * This cannot be done with SYSRET, so use the IRET return path instead.
@@ -697,6 +711,20 @@ ENTRY(stub_x32_execve)
         CFI_ENDPROC
 END(stub_x32_execve)
 
+ENTRY(stub_x32_execveat)
+        CFI_STARTPROC
+        addq $8, %rsp
+        PARTIAL_FRAME 0
+        SAVE_REST
+        FIXUP_TOP_OF_STACK %r11
+        call compat_sys_execveat
+        RESTORE_TOP_OF_STACK %r11
+        movq %rax,RAX(%rsp)
+        RESTORE_REST
+        jmp int_ret_from_sys_call
+        CFI_ENDPROC
+END(stub_x32_execveat)
+
 #endif
 
 /*