Sync up linux and svr compat elf fixup functions for exec(). These

functions are now all basically identical except that alpha linux uses
Elf64 arguments and svr4 and i386 linux use Elf32.  The fixups include
changing the first argument to be a register_t ** to match the prototype
for fixup functions, asserting that the process in the image_params struct
is always curproc and removing unnecessary locking to read credentials as a
result, and a few style fixes.

3 files changed, 23 insertions, 22 deletions

diff --git a/sys/alpha/linux/linux_sysvec.c b/sys/alpha/linux/linux_sysvec.c
index 9e9e1f9..40deced 100644
--- a/sys/alpha/linux/linux_sysvec.c
+++ b/sys/alpha/linux/linux_sysvec.c
@@ -81,25 +81,26 @@ SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler);
 
 void osendsig(sig_t catcher, int sig, sigset_t *mask, u_long code);
 
-static int	elf_linux_fixup(long **stack_base,
+static int	elf_linux_fixup(register_t **stack_base,
     struct image_params *iparams);
 static int	exec_linux_imgact_try(struct image_params *iparams);
 
 static int
-elf_linux_fixup(long **stack_base, struct image_params *imgp)
+elf_linux_fixup(register_t **stack_base, struct image_params *imgp)
 {
-	long *pos;
 	Elf64_Auxargs *args;
+	register_t *pos;
 
+	KASSERT(curthread->td_proc == imgp->proc &&
+	    (curthread->td_proc->p_flag & P_THREADED) == 0,
+	    ("unsafe elf_linux_fixup(), should be curproc"));
 	args = (Elf64_Auxargs *)imgp->auxargs;
 	pos = *stack_base + (imgp->argc + imgp->envc + 2);
 
-	if (args->trace) {
+	if (args->trace)
 		AUXARGS_ENTRY(pos, AT_DEBUG, 1);
-	}
-	if (args->execfd != -1) {
+	if (args->execfd != -1)
 		AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
-	}       
 	AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
 	AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
 	AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
@@ -107,19 +108,17 @@ elf_linux_fixup(long **stack_base, struct image_params *imgp)
 	AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
 	AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
 	AUXARGS_ENTRY(pos, AT_BASE, args->base);
-	PROC_LOCK(imgp->proc);
 	AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid);
 	AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid);
 	AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid);
 	AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid);
-	PROC_UNLOCK(imgp->proc);
 	AUXARGS_ENTRY(pos, AT_NULL, 0);
 	
 	free(imgp->auxargs, M_TEMP);      
 	imgp->auxargs = NULL;
 
 	(*stack_base)--;
-	**stack_base = (long)imgp->argc;
+	**stack_base = (register_t)imgp->argc;
 	return 0;
 }
 
diff --git a/sys/compat/svr4/svr4_sysvec.c b/sys/compat/svr4/svr4_sysvec.c
index 1d4ad6e..ec8ce8b 100644
--- a/sys/compat/svr4/svr4_sysvec.c
+++ b/sys/compat/svr4/svr4_sysvec.c
@@ -206,17 +206,19 @@ const char      svr4_emul_path[] = "/compat/svr4";
 static int
 svr4_fixup(register_t **stack_base, struct image_params *imgp)
 {
-	Elf32_Auxargs *args = (Elf32_Auxargs *)imgp->auxargs;
+	Elf32_Auxargs *args;
 	register_t *pos;
              
+	KASSERT(curthread->td_proc == imgp->proc &&
+	    (curthread->td_proc->p_flag & P_THREADED) == 0,
+	    ("unsafe svr4_fixup(), should be curproc"));
+	args = (Elf32_Auxargs *)imgp->auxargs;
 	pos = *stack_base + (imgp->argc + imgp->envc + 2);  
     
-	if (args->trace) {
+	if (args->trace)
 		AUXARGS_ENTRY(pos, AT_DEBUG, 1);
-	}
-	if (args->execfd != -1) {
+	if (args->execfd != -1)
 		AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
-	}       
 	AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
 	AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
 	AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
@@ -224,19 +226,17 @@ svr4_fixup(register_t **stack_base, struct image_params *imgp)
 	AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
 	AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
 	AUXARGS_ENTRY(pos, AT_BASE, args->base);
-	PROC_LOCK(imgp->proc);
 	AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid);
 	AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid);
 	AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid);
 	AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid);
-	PROC_UNLOCK(imgp->proc);
 	AUXARGS_ENTRY(pos, AT_NULL, 0);
 	
 	free(imgp->auxargs, M_TEMP);      
 	imgp->auxargs = NULL;
 
 	(*stack_base)--;
-	**stack_base = (int)imgp->argc;
+	**stack_base = (register_t)imgp->argc;
 	return 0;
 }
 
diff --git a/sys/i386/linux/linux_sysvec.c b/sys/i386/linux/linux_sysvec.c
index 407348d..c324f82 100644
--- a/sys/i386/linux/linux_sysvec.c
+++ b/sys/i386/linux/linux_sysvec.c
@@ -228,9 +228,13 @@ linux_fixup(register_t **stack_base, struct image_params *imgp)
 static int
 elf_linux_fixup(register_t **stack_base, struct image_params *imgp)
 {
-	Elf32_Auxargs *args = (Elf32_Auxargs *)imgp->auxargs;
+	Elf32_Auxargs *args;
 	register_t *pos;
 
+	KASSERT(curthread->td_proc == imgp->proc &&
+	    (curthread->td_proc->p_flag & P_THREADED) == 0,
+	    ("unsafe elf_linux_fixup(), should be curproc"));
+	args = (Elf32_Auxargs *)imgp->auxargs;
 	pos = *stack_base + (imgp->argc + imgp->envc + 2);
 
 	if (args->trace)
@@ -244,19 +248,17 @@ elf_linux_fixup(register_t **stack_base, struct image_params *imgp)
 	AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
 	AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
 	AUXARGS_ENTRY(pos, AT_BASE, args->base);
-	PROC_LOCK(imgp->proc);
 	AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid);
 	AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid);
 	AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid);
 	AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid);
-	PROC_UNLOCK(imgp->proc);
 	AUXARGS_ENTRY(pos, AT_NULL, 0);
 
 	free(imgp->auxargs, M_TEMP);
 	imgp->auxargs = NULL;
 
 	(*stack_base)--;
-	**stack_base = (long)imgp->argc;
+	**stack_base = (register_t)imgp->argc;
 	return 0;
 }