From: Kris Van Hees <kris.van.hees@oracle.com>
Date: Sat, 11 Jul 2015 04:18:28 +0000 (-0100)
Subject: dtrace: accomodate changes in the 4.1 kernel for sparc64
X-Git-Tag: v4.1.12-92~313^2
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=48431b3da06677ff1abcd51eb88106a32f3bfc0f;p=users%2Fjedix%2Flinux-maple.git

dtrace: accomodate changes in the 4.1 kernel for sparc64

The handling of some system calls changed:

- The sigaltstack system call is no longer a special case using a
  stub in assembler.
- New system call: execveat

This commit also fixes a problem with the support for the execveat
system call on x86_64, where not all arguments were being passed in
the entry probe for that new system call.

Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
Acked-by: Nick Alcock <nick.alcock@oracle.com>
---

diff --git a/arch/sparc/include/asm/dtrace_syscall.h b/arch/sparc/include/asm/dtrace_syscall.h
index 538f2c15ef88..4bdc51021147 100644
--- a/arch/sparc/include/asm/dtrace_syscall.h
+++ b/arch/sparc/include/asm/dtrace_syscall.h
@@ -1,9 +1,9 @@
 /* Copyright (C) 2011-2014 Oracle, Inc. */
 
 DTRACE_SYSCALL_STUB(EXECVE,		execve)
+DTRACE_SYSCALL_STUB(EXECVEAT,		execveat)
 DTRACE_SYSCALL_STUB(PIPE,		pipe)
 DTRACE_SYSCALL_STUB(MEMORY_ORDERING,	memory_ordering)
-DTRACE_SYSCALL_STUB(SIGALTSTACK,	sigaltstack)
 DTRACE_SYSCALL_STUB(RT_SIGRETURN,	rt_sigreturn)
 DTRACE_SYSCALL_STUB(VFORK,		vfork)
 DTRACE_SYSCALL_STUB(FORK,		fork)
diff --git a/arch/sparc/kernel/dtrace_syscall.c b/arch/sparc/kernel/dtrace_syscall.c
index 18ebb06bf7f5..2224b3c1a38b 100644
--- a/arch/sparc/kernel/dtrace_syscall.c
+++ b/arch/sparc/kernel/dtrace_syscall.c
@@ -11,6 +11,7 @@
 #include <linux/fs.h>
 #include <linux/kallsyms.h>
 #include <linux/module.h>
+#include <linux/namei.h>
 #include <linux/sched.h>
 #include <linux/syscalls.h>
 #include <asm/compat.h>
@@ -183,7 +184,37 @@ asmlinkage long dtrace_sys_execve(const char __user *name,
 
 	rc = do_execve(getname(name), argv, envp);
 
-out:
+	if ((id = sc->stsy_return) != DTRACE_IDNONE)
+		(*systrace_probe)(id, (uintptr_t)rc, (uintptr_t)rc,
+				  (uintptr_t)((uint64_t)rc >> 32), 0, 0, 0);
+
+	return rc;
+}
+
+asmlinkage long dtrace_sys_execveat(int fd, const char __user *name,
+				    const char __user *const __user *argv,
+				    const char __user *const __user *envp,
+				    int flags)
+{
+	long			rc = 0;
+	dtrace_id_t		id;
+	dtrace_syscalls_t	*sc;
+	int			lookup_flags =
+				(flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
+
+	sc = &systrace_info.sysent[__NR_execveat];
+
+	if ((id = sc->stsy_entry) != DTRACE_IDNONE)
+		(*systrace_probe)(id, fd, (uintptr_t)name, (uintptr_t)argv,
+				  (uintptr_t)envp, flags, 0);
+
+	/*
+	 * FIXME: Add stop functionality for DTrace.
+	 */
+
+	rc = do_execveat(fd, getname_flags(name, lookup_flags, NULL), argv,
+			 envp, flags);
+
 	if ((id = sc->stsy_return) != DTRACE_IDNONE)
 		(*systrace_probe)(id, (uintptr_t)rc, (uintptr_t)rc,
 				  (uintptr_t)((uint64_t)rc >> 32), 0, 0, 0);
diff --git a/arch/sparc/kernel/dtrace_syscall_stubs.S b/arch/sparc/kernel/dtrace_syscall_stubs.S
index 65377ba69b95..19ddaf81011b 100644
--- a/arch/sparc/kernel/dtrace_syscall_stubs.S
+++ b/arch/sparc/kernel/dtrace_syscall_stubs.S
@@ -17,6 +17,12 @@
 	 flushw
 	ENDPROC(dtrace_stub_execve)
 
+	ENTRY(dtrace_stub_execveat)
+	set	dtrace_sys_execveat, %g1
+	jmpl	%g1, %g0
+	 flushw
+	ENDPROC(dtrace_stub_execveat)
+
 	ENTRY(dtrace_stub_pipe)
 	ba,pt	%xcc, dtrace_sys_pipe
 	 add	%sp, PTREGS_OFF, %o0
@@ -27,11 +33,6 @@
 	 add	%sp, PTREGS_OFF, %o1
 	ENDPROC(dtrace_stub_memory_ordering)
 
-	ENTRY(dtrace_stub_sigaltstack)
-	ba,pt	%xcc, dtrace_sys_sigaltstack
-	 add	%i6, STACK_BIAS, %o2
-	ENDPROC(dtrace_stub_sigaltstack)
-
 	ENTRY(dtrace_stub_rt_sigreturn)
 	add	%sp, PTREGS_OFF, %o0
 	call	dtrace_sys_rt_sigreturn
diff --git a/arch/x86/kernel/dtrace_syscall.c b/arch/x86/kernel/dtrace_syscall.c
index f9091383285f..21a8dd806a24 100644
--- a/arch/x86/kernel/dtrace_syscall.c
+++ b/arch/x86/kernel/dtrace_syscall.c
@@ -230,8 +230,8 @@ long dtrace_sys_execveat(int fd, const char __user *name,
 	sc = &systrace_info.sysent[__NR_execveat];
 
 	if ((id = sc->stsy_entry) != DTRACE_IDNONE)
-		(*systrace_probe)(id, (uintptr_t)name, (uintptr_t)argv,
-				  (uintptr_t)envp, 0, 0, 0);
+		(*systrace_probe)(id, fd, (uintptr_t)name, (uintptr_t)argv,
+				  (uintptr_t)envp, flags, 0);
 
 	/*
 	 * FIXME: Add stop functionality for DTrace.