Index: head/sys/amd64/amd64/elf_machdep.c
===================================================================
--- head/sys/amd64/amd64/elf_machdep.c
+++ head/sys/amd64/amd64/elf_machdep.c
@@ -68,6 +68,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings	= exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/arm/arm/elf_machdep.c
===================================================================
--- head/sys/arm/arm/elf_machdep.c
+++ head/sys/arm/arm/elf_machdep.c
@@ -75,6 +75,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings = exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/arm64/arm64/elf32_machdep.c
===================================================================
--- head/sys/arm64/arm64/elf32_machdep.c
+++ head/sys/arm64/arm64/elf32_machdep.c
@@ -92,6 +92,7 @@
 	.sv_usrstack	= FREEBSD32_USRSTACK,
 	.sv_psstrings	= FREEBSD32_PS_STRINGS,
 	.sv_stackprot	= VM_PROT_READ | VM_PROT_WRITE,
+	.sv_copyout_auxargs = elf32_freebsd_copyout_auxargs,
 	.sv_copyout_strings = freebsd32_copyout_strings,
 	.sv_setregs	= freebsd32_setregs,
 	.sv_fixlimit	= NULL, // XXX
Index: head/sys/arm64/arm64/elf_machdep.c
===================================================================
--- head/sys/arm64/arm64/elf_machdep.c
+++ head/sys/arm64/arm64/elf_machdep.c
@@ -76,6 +76,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_READ | VM_PROT_WRITE,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings = exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/compat/freebsd32/freebsd32_misc.c
===================================================================
--- head/sys/compat/freebsd32/freebsd32_misc.c
+++ head/sys/compat/freebsd32/freebsd32_misc.c
@@ -3195,14 +3195,8 @@
 	if (imgp->sysent->sv_stackgap != NULL)
 		imgp->sysent->sv_stackgap(imgp, (u_long *)&vectp);
 
-	if (imgp->auxargs) {
-		/*
-		 * Allocate room on the stack for the ELF auxargs
-		 * array.  It has up to AT_COUNT entries.
-		 */
-		vectp -= howmany(AT_COUNT * sizeof(Elf32_Auxinfo),
-		    sizeof(*vectp));
-	}
+	if (imgp->auxargs)
+		imgp->sysent->sv_copyout_auxargs(imgp, (u_long *)&vectp);
 
 	/*
 	 * Allocate room for the argv[] and env vectors including the
Index: head/sys/compat/ia32/ia32_sysvec.c
===================================================================
--- head/sys/compat/ia32/ia32_sysvec.c
+++ head/sys/compat/ia32/ia32_sysvec.c
@@ -114,6 +114,7 @@
 	.sv_usrstack	= FREEBSD32_USRSTACK,
 	.sv_psstrings	= FREEBSD32_PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs	= elf32_freebsd_copyout_auxargs,
 	.sv_copyout_strings	= freebsd32_copyout_strings,
 	.sv_setregs	= ia32_setregs,
 	.sv_fixlimit	= ia32_fixlimit,
Index: head/sys/i386/i386/elf_machdep.c
===================================================================
--- head/sys/i386/i386/elf_machdep.c
+++ head/sys/i386/i386/elf_machdep.c
@@ -70,6 +70,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings	= exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/kern/imgact_elf.c
===================================================================
--- head/sys/kern/imgact_elf.c
+++ head/sys/kern/imgact_elf.c
@@ -1289,7 +1289,7 @@
 		addr = et_dyn_addr;
 
 	/*
-	 * Construct auxargs table (used by the fixup routine)
+	 * Construct auxargs table (used by the copyout_auxargs routine)
 	 */
 	elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_NOWAIT);
 	if (elf_auxargs == NULL) {
@@ -1323,16 +1323,13 @@
 
 #define	suword __CONCAT(suword, __ELF_WORD_SIZE)
 
-int
-__elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp)
+void
+__elfN(freebsd_copyout_auxargs)(struct image_params *imgp, u_long *base)
 {
 	Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs;
 	Elf_Auxinfo *argarray, *pos;
-	Elf_Addr *base, *auxbase;
-	int error;
+	u_long auxlen;
 
-	base = (Elf_Addr *)*stack_base;
-	auxbase = base + imgp->args->argc + 1 + imgp->args->envc + 1;
 	argarray = pos = malloc(AT_COUNT * sizeof(*pos), M_TEMP,
 	    M_WAITOK | M_ZERO);
 
@@ -1376,11 +1373,18 @@
 	imgp->auxargs = NULL;
 	KASSERT(pos - argarray <= AT_COUNT, ("Too many auxargs"));
 
-	error = copyout(argarray, auxbase, sizeof(*argarray) * AT_COUNT);
+	auxlen = sizeof(*argarray) * (pos - argarray);
+	*base -= auxlen;
+	copyout(argarray, (void *)*base, auxlen);
 	free(argarray, M_TEMP);
-	if (error != 0)
-		return (error);
+}
 
+int
+__elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp)
+{
+	Elf_Addr *base;
+
+	base = (Elf_Addr *)*stack_base;
 	base--;
 	if (suword(base, imgp->args->argc) == -1)
 		return (EFAULT);
Index: head/sys/kern/kern_exec.c
===================================================================
--- head/sys/kern/kern_exec.c
+++ head/sys/kern/kern_exec.c
@@ -1637,14 +1637,8 @@
 	if (imgp->sysent->sv_stackgap != NULL)
 		imgp->sysent->sv_stackgap(imgp, (u_long *)&vectp);
 
-	if (imgp->auxargs) {
-		/*
-		 * Allocate room on the stack for the ELF auxargs
-		 * array.  It has up to AT_COUNT entries.
-		 */
-		vectp -= howmany(AT_COUNT * sizeof(Elf_Auxinfo),
-		    sizeof(*vectp));
-	}
+	if (imgp->auxargs)
+		imgp->sysent->sv_copyout_auxargs(imgp, (u_long *)&vectp);
 
 	/*
 	 * Allocate room for the argv[] and env vectors including the
Index: head/sys/mips/mips/elf_machdep.c
===================================================================
--- head/sys/mips/mips/elf_machdep.c
+++ head/sys/mips/mips/elf_machdep.c
@@ -71,6 +71,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings = exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
@@ -125,6 +126,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings = exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/mips/mips/freebsd32_machdep.c
===================================================================
--- head/sys/mips/mips/freebsd32_machdep.c
+++ head/sys/mips/mips/freebsd32_machdep.c
@@ -94,6 +94,7 @@
 	.sv_usrstack	= FREEBSD32_USRSTACK,
 	.sv_psstrings	= FREEBSD32_PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings = freebsd32_copyout_strings,
 	.sv_setregs	= freebsd32_exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/powerpc/powerpc/elf32_machdep.c
===================================================================
--- head/sys/powerpc/powerpc/elf32_machdep.c
+++ head/sys/powerpc/powerpc/elf32_machdep.c
@@ -87,6 +87,7 @@
 	.sv_errtbl	= NULL,
 	.sv_transtrap	= NULL,
 	.sv_fixup	= __elfN(freebsd_fixup),
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_sendsig	= sendsig,
 	.sv_sigcode	= sigcode32,
 	.sv_szsigcode	= &szsigcode32,
Index: head/sys/powerpc/powerpc/elf64_machdep.c
===================================================================
--- head/sys/powerpc/powerpc/elf64_machdep.c
+++ head/sys/powerpc/powerpc/elf64_machdep.c
@@ -74,6 +74,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings = exec_copyout_strings,
 	.sv_setregs	= exec_setregs_funcdesc,
 	.sv_fixlimit	= NULL,
@@ -111,6 +112,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_ALL,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings = exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/riscv/riscv/elf_machdep.c
===================================================================
--- head/sys/riscv/riscv/elf_machdep.c
+++ head/sys/riscv/riscv/elf_machdep.c
@@ -79,6 +79,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_READ | VM_PROT_WRITE,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings	= exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/sparc64/sparc64/elf_machdep.c
===================================================================
--- head/sys/sparc64/sparc64/elf_machdep.c
+++ head/sys/sparc64/sparc64/elf_machdep.c
@@ -75,6 +75,7 @@
 	.sv_usrstack	= USRSTACK,
 	.sv_psstrings	= PS_STRINGS,
 	.sv_stackprot	= VM_PROT_READ | VM_PROT_WRITE,
+	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
 	.sv_copyout_strings = exec_copyout_strings,
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
Index: head/sys/sys/imgact_elf.h
===================================================================
--- head/sys/sys/imgact_elf.h
+++ head/sys/sys/imgact_elf.h
@@ -99,6 +99,7 @@
 int	__elfN(coredump)(struct thread *, struct vnode *, off_t, int);
 size_t	__elfN(populate_note)(int, void *, void *, size_t, void **);
 void	__elfN(stackgap)(struct image_params *, u_long *);
+void	__elfN(freebsd_copyout_auxargs)(struct image_params *, u_long *);
 
 /* Machine specific function to dump per-thread information. */
 void	__elfN(dump_thread)(struct thread *, void *, size_t *);
Index: head/sys/sys/sysent.h
===================================================================
--- head/sys/sys/sysent.h
+++ head/sys/sys/sysent.h
@@ -110,6 +110,7 @@
 					/* function to dump core, or NULL */
 	int		(*sv_imgact_try)(struct image_params *);
 	void		(*sv_stackgap)(struct image_params *, u_long *);
+	void		(*sv_copyout_auxargs)(struct image_params *, u_long *);
 	int		sv_minsigstksz;	/* minimum signal stack size */
 	vm_offset_t	sv_minuser;	/* VM_MIN_ADDRESS */
 	vm_offset_t	sv_maxuser;	/* VM_MAXUSER_ADDRESS */