Back out proc locking to protect p_ucred for obtaining additional

references along with the actual obtaining of additional references.

6 files changed, 18 insertions, 84 deletions

diff --git a/sys/compat/linux/linux_file.c b/sys/compat/linux/linux_file.c
index 1bbe4cc..4736ddc 100644
--- a/sys/compat/linux/linux_file.c
+++ b/sys/compat/linux/linux_file.c
@@ -405,7 +405,6 @@ linux_getdents(struct proc *p, struct linux_getdents_args *args)
     int buflen, error, eofflag, nbytes, justone;
     u_long *cookies = NULL, *cookiep;
     int ncookies;
-    struct ucred *uc;
 
 #ifdef DEBUG
     printf("Linux-emul(%d): getdents(%d, *, %d)\n",
@@ -423,13 +422,7 @@ linux_getdents(struct proc *p, struct linux_getdents_args *args)
     if (vp->v_type != VDIR)
 	return (EINVAL);
 
-    PROC_LOCK(p);
-    uc = p->p_ucred;
-    crhold(uc);
-    PROC_UNLOCK(p);
-    error = VOP_GETATTR(vp, &va, uc, p);
-    crfree(uc);
-    if (error) {
+    if ((error = VOP_GETATTR(vp, &va, p->p_ucred, p))) {
 	return error;
     }
 
diff --git a/sys/compat/linux/linux_misc.c b/sys/compat/linux/linux_misc.c
index 10eaa6e..0caff43 100644
--- a/sys/compat/linux/linux_misc.c
+++ b/sys/compat/linux/linux_misc.c
@@ -185,7 +185,6 @@ linux_uselib(struct proc *p, struct linux_uselib_args *args)
     struct vnode *vp;
     struct exec *a_out;
     struct vattr attr;
-    struct ucred *uc;
     vm_offset_t vmaddr;
     unsigned long file_offset;
     vm_offset_t buffer;
@@ -237,21 +236,14 @@ linux_uselib(struct proc *p, struct linux_uselib_args *args)
     /*
      * Executable?
      */
-    PROC_LOCK(p);
-    uc = p->p_ucred;
-    crhold(uc);
-    PROC_UNLOCK(p);
-    error = VOP_GETATTR(vp, &attr, uc, p);
-    if (error) {
-	crfree(uc);
+    error = VOP_GETATTR(vp, &attr, p->p_ucred, p);
+    if (error)
 	goto cleanup;
-    }
 
     if ((vp->v_mount->mnt_flag & MNT_NOEXEC) ||
 	((attr.va_mode & 0111) == 0) ||
 	(attr.va_type != VREG)) {
 	    error = ENOEXEC;
-	    crfree(uc);
 	    goto cleanup;
     }
 
@@ -260,21 +252,17 @@ linux_uselib(struct proc *p, struct linux_uselib_args *args)
      */
     if (attr.va_size == 0) {
 	error = ENOEXEC;
-	crfree(uc);
 	goto cleanup;
     }
 
     /*
      * Can we access it?
      */
-    error = VOP_ACCESS(vp, VEXEC, uc, p);
-    if (error) {
-	crfree(uc);
+    error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p);
+    if (error)
 	goto cleanup;
-    }
 
-    error = VOP_OPEN(vp, FREAD, uc, p);
-    crfree(uc);
+    error = VOP_OPEN(vp, FREAD, p->p_ucred, p);
     if (error)
 	goto cleanup;
 
diff --git a/sys/compat/linux/linux_util.c b/sys/compat/linux/linux_util.c
index f4fe8d7..6399805 100644
--- a/sys/compat/linux/linux_util.c
+++ b/sys/compat/linux/linux_util.c
@@ -62,7 +62,6 @@ linux_emul_find(p, sgp, prefix, path, pbuf, cflag)
 	struct nameidata	 ndroot;
 	struct vattr		 vat;
 	struct vattr		 vatroot;
-	struct ucred		*uc;
 	int			 error;
 	char			*ptr, *buf, *cp;
 	size_t			 sz, len;
@@ -141,18 +140,12 @@ linux_emul_find(p, sgp, prefix, path, pbuf, cflag)
 			return error;
 		}
 
-		PROC_LOCK(p);
-		uc = p->p_ucred;
-		crhold(uc);
-		PROC_UNLOCK(p);
-		if ((error = VOP_GETATTR(nd.ni_vp, &vat, uc, p)) != 0) {
-			crfree(uc);
+		if ((error = VOP_GETATTR(nd.ni_vp, &vat, p->p_ucred, p)) != 0) {
 			goto bad;
 		}
 
-		error = VOP_GETATTR(ndroot.ni_vp, &vatroot, uc, p);
-		crfree(uc);
-		if (error != 0) {
+		if ((error = VOP_GETATTR(ndroot.ni_vp, &vatroot, p->p_ucred, p))
+		    != 0) {
 			goto bad;
 		}
 
diff --git a/sys/compat/pecoff/imgact_pecoff.c b/sys/compat/pecoff/imgact_pecoff.c
index 88c3342..6dff6ba 100644
--- a/sys/compat/pecoff/imgact_pecoff.c
+++ b/sys/compat/pecoff/imgact_pecoff.c
@@ -162,7 +162,7 @@ static int
 pecoff_coredump(register struct proc * p, register struct vnode * vp,
 		off_t limit)
 {
-	register struct ucred *cred;
+	register struct ucred *cred = p->p_ucred;
 	register struct vmspace *vm = p->p_vmspace;
 	int             error;
 #ifdef PECOFF_DEBUG
@@ -184,10 +184,6 @@ pecoff_coredump(register struct proc * p, register struct vnode * vp,
 	ent = &map->header;
 	printf("%p %p %p\n", ent, ent->prev, ent->next);
 #endif
-	PROC_LOCK(p);
-	cred = p->p_ucred;
-	crhold(cred);
-	PROC_UNLOCK(p);
 	error = cpu_coredump(p, vp, cred);
 	if (error == 0)
 		error = vn_rdwr(UIO_WRITE, vp, vm->vm_daddr,
@@ -199,7 +195,6 @@ pecoff_coredump(register struct proc * p, register struct vnode * vp,
 				round_page(ctob(vm->vm_ssize)),
 		   (off_t) ctob(UPAGES) + ctob(vm->vm_dsize), UIO_USERSPACE,
 			    IO_NODELOCKED | IO_UNIT, cred, (int *) NULL, p);
-	crfree(cred);
 	return (error);
 
 }
@@ -605,15 +600,10 @@ pecoff_read_from(p, vp, pos, buf, siz)
 {
 	int             error;
 	size_t          resid;
-	struct ucred	*uc;
 
-	PROC_LOCK(p);
-	uc = p->p_ucred;
-	crhold(uc);
-	PROC_UNLOCK(p);
 	error = vn_rdwr(UIO_READ, vp, buf, siz, pos,
-			UIO_SYSSPACE, IO_NODELOCKED, uc, &resid, p);
-	crfree(uc);
+			UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred,
+			&resid, p);
 	if (error)
 		return error;
 
diff --git a/sys/compat/svr4/svr4_fcntl.c b/sys/compat/svr4/svr4_fcntl.c
index 3b8adad..c2b865a 100644
--- a/sys/compat/svr4/svr4_fcntl.c
+++ b/sys/compat/svr4/svr4_fcntl.c
@@ -249,7 +249,6 @@ fd_revoke(p, fd)
 	struct vnode *vp;
 	struct mount *mp;
 	struct vattr vattr;
-	struct ucred *uc;
 	int error, *retval;
 
 	retval = p->p_retval;
@@ -266,20 +265,12 @@ fd_revoke(p, fd)
 		goto out;
 	}
 
-	PROC_LOCK(p);
-	uc = p->p_ucred;
-	crhold(uc);
-	PROC_UNLOCK(p);
-	if ((error = VOP_GETATTR(vp, &vattr, uc, p)) != 0) {
-		crfree(uc);
+	if ((error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) != 0)
 		goto out;
-	}
 
-	if (uc->cr_uid != vattr.va_uid && (error = suser(p)) != 0) {
-		crfree(uc);
+	if (p->p_ucred->cr_uid != vattr.va_uid &&
+	    (error = suser(p)) != 0)
 		goto out;
-	}
-	crfree(uc);
 
 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
 		goto out;
@@ -303,7 +294,6 @@ fd_truncate(p, fd, flp)
 	off_t start, length;
 	struct vnode *vp;
 	struct vattr vattr;
-	struct ucred *uc;
 	int error, *retval;
 	struct ftruncate_args ft;
 
@@ -319,13 +309,7 @@ fd_truncate(p, fd, flp)
 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO)
 		return ESPIPE;
 
-	PROC_LOCK(p);
-	uc = p->p_ucred;
-	crhold(uc);
-	PROC_UNLOCK(p);
-	error = VOP_GETATTR(vp, &vattr, uc, p);
-	crfree(uc);
-	if (error != 0)
+	if ((error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) != 0)
 		return error;
 
 	length = vattr.va_size;
diff --git a/sys/compat/svr4/svr4_misc.c b/sys/compat/svr4/svr4_misc.c
index 62d0da9..b976c2d 100644
--- a/sys/compat/svr4/svr4_misc.c
+++ b/sys/compat/svr4/svr4_misc.c
@@ -250,7 +250,6 @@ svr4_sys_getdents64(p, uap)
 	struct uio auio;
 	struct iovec aiov;
 	struct vattr va;
-	struct ucred *uc;
 	off_t off;
 	struct svr4_dirent64 svr4_dirent;
 	int buflen, error, eofflag, nbytes, justone;
@@ -271,13 +270,7 @@ svr4_sys_getdents64(p, uap)
 	if (vp->v_type != VDIR)
 		return (EINVAL);
 
-	PROC_LOCK(p);
-	uc = p->p_ucred;
-	crhold(uc);
-	PROC_UNLOCK(p);
-	error = VOP_GETATTR(vp, &va, uc, p);
-	crfree(uc);
-	if (error != 0) {
+	if ((error = VOP_GETATTR(vp, &va, p->p_ucred, p))) {
 		return error;
 	}
 
@@ -599,7 +592,6 @@ svr4_sys_fchroot(p, uap)
 	struct filedesc	*fdp = p->p_fd;
 	struct vnode	*vp;
 	struct file	*fp;
-	struct ucred	*uc;
 	int		 error;
 
 	if ((error = suser(p)) != 0)
@@ -610,14 +602,8 @@ svr4_sys_fchroot(p, uap)
 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
 	if (vp->v_type != VDIR)
 		error = ENOTDIR;
-	else {
-		PROC_LOCK(p);
-		uc = p->p_ucred;
-		crhold(uc);
-		PROC_UNLOCK(p);
+	else
 		error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p);
-		crfree(uc);
-	}
 	VOP_UNLOCK(vp, 0, p);
 	if (error)
 		return error;