Merge branch 'work.memdup_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull memdup_user() conversions from Al Viro:
 "A fairly self-contained series - hunting down open-coded memdup_user()
  and memdup_user_nul() instances"

* 'work.memdup_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  bpf: don't open-code memdup_user()
  kimage_file_prepare_segments(): don't open-code memdup_user()
  ethtool: don't open-code memdup_user()
  do_ip_setsockopt(): don't open-code memdup_user()
  do_ipv6_setsockopt(): don't open-code memdup_user()
  irda: don't open-code memdup_user()
  xfrm_user_policy(): don't open-code memdup_user()
  ima_write_policy(): don't open-code memdup_user_nul()
  sel_write_validatetrans(): don't open-code memdup_user_nul()

kernel/bpf/syscall.c

@@ -410,14 +410,11 @@ static int map_lookup_elem(union bpf_attr *attr)
 	if (IS_ERR(map))
 		return PTR_ERR(map);
 
-	err = -ENOMEM;
-	key = kmalloc(map->key_size, GFP_USER);
-	if (!key)
+	key = memdup_user(ukey, map->key_size);
+	if (IS_ERR(key)) {
+		err = PTR_ERR(key);
 		goto err_put;
-
-	err = -EFAULT;
-	if (copy_from_user(key, ukey, map->key_size) != 0)
-		goto free_key;
+	}
 
 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
@@ -493,14 +490,11 @@ static int map_update_elem(union bpf_attr *attr)
 	if (IS_ERR(map))
 		return PTR_ERR(map);
 
-	err = -ENOMEM;
-	key = kmalloc(map->key_size, GFP_USER);
-	if (!key)
+	key = memdup_user(ukey, map->key_size);
+	if (IS_ERR(key)) {
+		err = PTR_ERR(key);
 		goto err_put;
-
-	err = -EFAULT;
-	if (copy_from_user(key, ukey, map->key_size) != 0)
-		goto free_key;
+	}
 
 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
@@ -579,14 +573,11 @@ static int map_delete_elem(union bpf_attr *attr)
 	if (IS_ERR(map))
 		return PTR_ERR(map);
 
-	err = -ENOMEM;
-	key = kmalloc(map->key_size, GFP_USER);
-	if (!key)
+	key = memdup_user(ukey, map->key_size);
+	if (IS_ERR(key)) {
+		err = PTR_ERR(key);
 		goto err_put;
-
-	err = -EFAULT;
-	if (copy_from_user(key, ukey, map->key_size) != 0)
-		goto free_key;
+	}
 
 	preempt_disable();
 	__this_cpu_inc(bpf_prog_active);
@@ -598,7 +589,6 @@ static int map_delete_elem(union bpf_attr *attr)
 
 	if (!err)
 		trace_bpf_map_delete_elem(map, ufd, key);
-free_key:
 	kfree(key);
 err_put:
 	fdput(f);
@@ -627,14 +617,11 @@ static int map_get_next_key(union bpf_attr *attr)
 		return PTR_ERR(map);
 
 	if (ukey) {
-		err = -ENOMEM;
-		key = kmalloc(map->key_size, GFP_USER);
-		if (!key)
+		key = memdup_user(ukey, map->key_size);
+		if (IS_ERR(key)) {
+			err = PTR_ERR(key);
 			goto err_put;
-
-		err = -EFAULT;
-		if (copy_from_user(key, ukey, map->key_size) != 0)
-			goto free_key;
+		}
 	} else {
 		key = NULL;
 	}

kernel/kexec_file.c

@@ -162,16 +162,10 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
 	}
 
 	if (cmdline_len) {
-		image->cmdline_buf = kzalloc(cmdline_len, GFP_KERNEL);
-		if (!image->cmdline_buf) {
-			ret = -ENOMEM;
-			goto out;
-		}
-
-		ret = copy_from_user(image->cmdline_buf, cmdline_ptr,
-				     cmdline_len);
-		if (ret) {
-			ret = -EFAULT;
+		image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len);
+		if (IS_ERR(image->cmdline_buf)) {
+			ret = PTR_ERR(image->cmdline_buf);
+			image->cmdline_buf = NULL;
 			goto out;
 		}
 

net/core/ethtool.c

@@ -2322,16 +2322,12 @@ static int ethtool_set_tunable(struct net_device *dev, void __user *useraddr)
 	ret = ethtool_tunable_valid(&tuna);
 	if (ret)
 		return ret;
-	data = kmalloc(tuna.len, GFP_USER);
-	if (!data)
-		return -ENOMEM;
 	useraddr += sizeof(tuna);
-	ret = -EFAULT;
-	if (copy_from_user(data, useraddr, tuna.len))
-		goto out;
+	data = memdup_user(useraddr, tuna.len);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
 	ret = ops->set_tunable(dev, &tuna, data);
 
-out:
 	kfree(data);
 	return ret;
 }
@@ -2507,18 +2503,14 @@ static int set_phy_tunable(struct net_device *dev, void __user *useraddr)
 	ret = ethtool_phy_tunable_valid(&tuna);
 	if (ret)
 		return ret;
-	data = kmalloc(tuna.len, GFP_USER);
-	if (!data)
-		return -ENOMEM;
 	useraddr += sizeof(tuna);
-	ret = -EFAULT;
-	if (copy_from_user(data, useraddr, tuna.len))
-		goto out;
+	data = memdup_user(useraddr, tuna.len);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
 	mutex_lock(&phydev->lock);
 	ret = phydev->drv->set_tunable(phydev, &tuna, data);
 	mutex_unlock(&phydev->lock);
 
-out:
 	kfree(data);
 	return ret;
 }

net/ipv4/ip_sockglue.c

@@ -934,14 +934,9 @@ static int do_ip_setsockopt(struct sock *sk, int level,
 			err = -ENOBUFS;
 			break;
 		}
-		msf = kmalloc(optlen, GFP_KERNEL);
-		if (!msf) {
-			err = -ENOBUFS;
-			break;
-		}
-		err = -EFAULT;
-		if (copy_from_user(msf, optval, optlen)) {
-			kfree(msf);
+		msf = memdup_user(optval, optlen);
+		if (IS_ERR(msf)) {
+			err = PTR_ERR(msf);
 			break;
 		}
 		/* numsrc >= (1G-4) overflow in 32 bits */
@@ -1090,14 +1085,11 @@ static int do_ip_setsockopt(struct sock *sk, int level,
 			err = -ENOBUFS;
 			break;
 		}
-		gsf = kmalloc(optlen, GFP_KERNEL);
-		if (!gsf) {
-			err = -ENOBUFS;
+		gsf = memdup_user(optval, optlen);
+		if (IS_ERR(gsf)) {
+			err = PTR_ERR(gsf);
 			break;
 		}
-		err = -EFAULT;
-		if (copy_from_user(gsf, optval, optlen))
-			goto mc_msf_out;
 
 		/* numsrc >= (4G-140)/128 overflow in 32 bits */
 		if (gsf->gf_numsrc >= 0x1ffffff ||

net/ipv6/ipv6_sockglue.c

@@ -735,14 +735,9 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 			retv = -ENOBUFS;
 			break;
 		}
-		gsf = kmalloc(optlen, GFP_KERNEL);
-		if (!gsf) {
-			retv = -ENOBUFS;
-			break;
-		}
-		retv = -EFAULT;
-		if (copy_from_user(gsf, optval, optlen)) {
-			kfree(gsf);
+		gsf = memdup_user(optval, optlen);
+		if (IS_ERR(gsf)) {
+			retv = PTR_ERR(gsf);
 			break;
 		}
 		/* numsrc >= (4G-140)/128 overflow in 32 bits */

net/irda/af_irda.c

@@ -1901,16 +1901,10 @@ static int irda_setsockopt(struct socket *sock, int level, int optname,
 			goto out;
 		}
 
-		ias_opt = kmalloc(sizeof(struct irda_ias_set), GFP_ATOMIC);
-		if (ias_opt == NULL) {
-			err = -ENOMEM;
-			goto out;
-		}
-
 		/* Copy query to the driver. */
-		if (copy_from_user(ias_opt, optval, optlen)) {
-			kfree(ias_opt);
-			err = -EFAULT;
+		ias_opt = memdup_user(optval, optlen);
+		if (IS_ERR(ias_opt)) {
+			err = PTR_ERR(ias_opt);
 			goto out;
 		}
 
@@ -2032,16 +2026,10 @@ static int irda_setsockopt(struct socket *sock, int level, int optname,
 			goto out;
 		}
 
-		ias_opt = kmalloc(sizeof(struct irda_ias_set), GFP_ATOMIC);
-		if (ias_opt == NULL) {
-			err = -ENOMEM;
-			goto out;
-		}
-
 		/* Copy query to the driver. */
-		if (copy_from_user(ias_opt, optval, optlen)) {
-			kfree(ias_opt);
-			err = -EFAULT;
+		ias_opt = memdup_user(optval, optlen);
+		if (IS_ERR(ias_opt)) {
+			err = PTR_ERR(ias_opt);
 			goto out;
 		}
 
@@ -2317,16 +2305,10 @@ static int irda_getsockopt(struct socket *sock, int level, int optname,
 			goto out;
 		}
 
-		ias_opt = kmalloc(sizeof(struct irda_ias_set), GFP_ATOMIC);
-		if (ias_opt == NULL) {
-			err = -ENOMEM;
-			goto out;
-		}
-
 		/* Copy query to the driver. */
-		if (copy_from_user(ias_opt, optval, len)) {
-			kfree(ias_opt);
-			err = -EFAULT;
+		ias_opt = memdup_user(optval, len);
+		if (IS_ERR(ias_opt)) {
+			err = PTR_ERR(ias_opt);
 			goto out;
 		}
 
@@ -2381,16 +2363,10 @@ static int irda_getsockopt(struct socket *sock, int level, int optname,
 			goto out;
 		}
 
-		ias_opt = kmalloc(sizeof(struct irda_ias_set), GFP_ATOMIC);
-		if (ias_opt == NULL) {
-			err = -ENOMEM;
-			goto out;
-		}
-
 		/* Copy query to the driver. */
-		if (copy_from_user(ias_opt, optval, len)) {
-			kfree(ias_opt);
-			err = -EFAULT;
+		ias_opt = memdup_user(optval, len);
+		if (IS_ERR(ias_opt)) {
+			err = PTR_ERR(ias_opt);
 			goto out;
 		}
 

security/selinux/selinuxfs.c

@@ -649,14 +649,12 @@ static ssize_t sel_write_validatetrans(struct file *file,
 	if (*ppos != 0)
 		goto out;
 
-	rc = -ENOMEM;
-	req = kzalloc(count + 1, GFP_KERNEL);
-	if (!req)
-		goto out;
-
-	rc = -EFAULT;
-	if (copy_from_user(req, buf, count))
+	req = memdup_user_nul(buf, count);
+	if (IS_ERR(req)) {
+		rc = PTR_ERR(req);
+		req = NULL;
 		goto out;
+	}
 
 	rc = -ENOMEM;
 	oldcon = kzalloc(count + 1, GFP_KERNEL);