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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-02-28 05:29:16 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-02-28 05:29:16 -0300
commit844e3cded9c8665e95b1e43b707a6c3adcbc901f (patch)
treedd9cccb325c949319a9de3e0cabad91d6261fa75 /fs/overlayfs
parent6d461a4fe7896faa1aec5a5417888cf179e46b9f (diff)
Linux-libre 4.4.3-gnu
Diffstat (limited to 'fs/overlayfs')
-rw-r--r--fs/overlayfs/copy_up.c41
-rw-r--r--fs/overlayfs/inode.c13
-rw-r--r--fs/overlayfs/readdir.c3
-rw-r--r--fs/overlayfs/super.c5
4 files changed, 46 insertions, 16 deletions
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 0a8983492..eff6319d5 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -22,9 +22,9 @@
int ovl_copy_xattr(struct dentry *old, struct dentry *new)
{
- ssize_t list_size, size;
- char *buf, *name, *value;
- int error;
+ ssize_t list_size, size, value_size = 0;
+ char *buf, *name, *value = NULL;
+ int uninitialized_var(error);
if (!old->d_inode->i_op->getxattr ||
!new->d_inode->i_op->getxattr)
@@ -41,29 +41,40 @@ int ovl_copy_xattr(struct dentry *old, struct dentry *new)
if (!buf)
return -ENOMEM;
- error = -ENOMEM;
- value = kmalloc(XATTR_SIZE_MAX, GFP_KERNEL);
- if (!value)
- goto out;
-
list_size = vfs_listxattr(old, buf, list_size);
if (list_size <= 0) {
error = list_size;
- goto out_free_value;
+ goto out;
}
for (name = buf; name < (buf + list_size); name += strlen(name) + 1) {
- size = vfs_getxattr(old, name, value, XATTR_SIZE_MAX);
- if (size <= 0) {
+retry:
+ size = vfs_getxattr(old, name, value, value_size);
+ if (size == -ERANGE)
+ size = vfs_getxattr(old, name, NULL, 0);
+
+ if (size < 0) {
error = size;
- goto out_free_value;
+ break;
+ }
+
+ if (size > value_size) {
+ void *new;
+
+ new = krealloc(value, size, GFP_KERNEL);
+ if (!new) {
+ error = -ENOMEM;
+ break;
+ }
+ value = new;
+ value_size = size;
+ goto retry;
}
+
error = vfs_setxattr(new, name, value, size, 0);
if (error)
- goto out_free_value;
+ break;
}
-
-out_free_value:
kfree(value);
out:
kfree(buf);
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 4060ffde8..b29036aa8 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -42,6 +42,19 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
int err;
struct dentry *upperdentry;
+ /*
+ * Check for permissions before trying to copy-up. This is redundant
+ * since it will be rechecked later by ->setattr() on upper dentry. But
+ * without this, copy-up can be triggered by just about anybody.
+ *
+ * We don't initialize inode->size, which just means that
+ * inode_newsize_ok() will always check against MAX_LFS_FILESIZE and not
+ * check for a swapfile (which this won't be anyway).
+ */
+ err = inode_change_ok(dentry->d_inode, attr);
+ if (err)
+ return err;
+
err = ovl_want_write(dentry);
if (err)
goto out;
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 70e9af551..adcb1398c 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -571,7 +571,8 @@ void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list)
(int) PTR_ERR(dentry));
continue;
}
- ovl_cleanup(upper->d_inode, dentry);
+ if (dentry->d_inode)
+ ovl_cleanup(upper->d_inode, dentry);
dput(dentry);
}
mutex_unlock(&upper->d_inode->i_mutex);
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index e38ee0fed..f42c9407f 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -9,6 +9,7 @@
#include <linux/fs.h>
#include <linux/namei.h>
+#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/security.h>
#include <linux/mount.h>
@@ -910,6 +911,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
}
sb->s_stack_depth = 0;
+ sb->s_maxbytes = MAX_LFS_FILESIZE;
if (ufs->config.upperdir) {
if (!ufs->config.workdir) {
pr_err("overlayfs: missing 'workdir'\n");
@@ -1053,6 +1055,9 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
root_dentry->d_fsdata = oe;
+ ovl_copyattr(ovl_dentry_real(root_dentry)->d_inode,
+ root_dentry->d_inode);
+
sb->s_magic = OVERLAYFS_SUPER_MAGIC;
sb->s_op = &ovl_super_operations;
sb->s_root = root_dentry;