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authorJames Morris <james.l.morris@oracle.com>2017-11-29 12:47:41 +1100
committerJames Morris <james.l.morris@oracle.com>2017-11-29 12:47:41 +1100
commitcf40a76e7d5874bb25f4404eecc58a2e033af885 (patch)
tree8fd81cbea03c87b3d41d7ae5b1d11eadd35d6ef5 /fs/overlayfs/util.c
parentab5348c9c23cd253f5902980d2d8fe067dc24c82 (diff)
parent4fbd8d194f06c8a3fd2af1ce560ddb31f7ec8323 (diff)
Merge tag 'v4.15-rc1' into next-seccomp
Linux 4.15-rc1
Diffstat (limited to 'fs/overlayfs/util.c')
-rw-r--r--fs/overlayfs/util.c69
1 files changed, 60 insertions, 9 deletions
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index f46ad75dc96a..d6bb1c9f5e7a 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -17,7 +17,6 @@
#include <linux/namei.h>
#include <linux/ratelimit.h>
#include "overlayfs.h"
-#include "ovl_entry.h"
int ovl_want_write(struct dentry *dentry)
{
@@ -125,7 +124,12 @@ void ovl_path_lower(struct dentry *dentry, struct path *path)
{
struct ovl_entry *oe = dentry->d_fsdata;
- *path = oe->numlower ? oe->lowerstack[0] : (struct path) { };
+ if (oe->numlower) {
+ path->mnt = oe->lowerstack[0].layer->mnt;
+ path->dentry = oe->lowerstack[0].dentry;
+ } else {
+ *path = (struct path) { };
+ }
}
enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path)
@@ -180,14 +184,14 @@ struct inode *ovl_inode_real(struct inode *inode)
}
-struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry)
+struct ovl_dir_cache *ovl_dir_cache(struct inode *inode)
{
- return OVL_I(d_inode(dentry))->cache;
+ return OVL_I(inode)->cache;
}
-void ovl_set_dir_cache(struct dentry *dentry, struct ovl_dir_cache *cache)
+void ovl_set_dir_cache(struct inode *inode, struct ovl_dir_cache *cache)
{
- OVL_I(d_inode(dentry))->cache = cache;
+ OVL_I(inode)->cache = cache;
}
bool ovl_dentry_is_opaque(struct dentry *dentry)
@@ -275,12 +279,19 @@ void ovl_inode_update(struct inode *inode, struct dentry *upperdentry)
}
}
-void ovl_dentry_version_inc(struct dentry *dentry)
+void ovl_dentry_version_inc(struct dentry *dentry, bool impurity)
{
struct inode *inode = d_inode(dentry);
WARN_ON(!inode_is_locked(inode));
- OVL_I(inode)->version++;
+ /*
+ * Version is used by readdir code to keep cache consistent. For merge
+ * dirs all changes need to be noted. For non-merge dirs, cache only
+ * contains impure (ones which have been copied up and have origins)
+ * entries, so only need to note changes to impure entries.
+ */
+ if (OVL_TYPE_MERGE(ovl_path_type(dentry)) || impurity)
+ OVL_I(inode)->version++;
}
u64 ovl_dentry_version_get(struct dentry *dentry)
@@ -322,6 +333,19 @@ void ovl_copy_up_end(struct dentry *dentry)
mutex_unlock(&OVL_I(d_inode(dentry))->lock);
}
+bool ovl_check_origin_xattr(struct dentry *dentry)
+{
+ int res;
+
+ res = vfs_getxattr(dentry, OVL_XATTR_ORIGIN, NULL, 0);
+
+ /* Zero size value means "copied up but origin unknown" */
+ if (res >= 0)
+ return true;
+
+ return false;
+}
+
bool ovl_check_dir_xattr(struct dentry *dentry, const char *name)
{
int res;
@@ -382,6 +406,11 @@ void ovl_set_flag(unsigned long flag, struct inode *inode)
set_bit(flag, &OVL_I(inode)->flags);
}
+void ovl_clear_flag(unsigned long flag, struct inode *inode)
+{
+ clear_bit(flag, &OVL_I(inode)->flags);
+}
+
bool ovl_test_flag(unsigned long flag, struct inode *inode)
{
return test_bit(flag, &OVL_I(inode)->flags);
@@ -418,7 +447,7 @@ void ovl_inuse_unlock(struct dentry *dentry)
}
}
-/* Called must hold OVL_I(inode)->oi_lock */
+/* Caller must hold OVL_I(inode)->lock */
static void ovl_cleanup_index(struct dentry *dentry)
{
struct inode *dir = ovl_indexdir(dentry->d_sb)->d_inode;
@@ -457,6 +486,9 @@ static void ovl_cleanup_index(struct dentry *dentry)
err = PTR_ERR(index);
if (!IS_ERR(index))
err = ovl_cleanup(dir, index);
+ else
+ index = NULL;
+
inode_unlock(dir);
if (err)
goto fail;
@@ -545,3 +577,22 @@ void ovl_nlink_end(struct dentry *dentry, bool locked)
mutex_unlock(&OVL_I(d_inode(dentry))->lock);
}
}
+
+int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)
+{
+ /* Workdir should not be the same as upperdir */
+ if (workdir == upperdir)
+ goto err;
+
+ /* Workdir should not be subdir of upperdir and vice versa */
+ if (lock_rename(workdir, upperdir) != NULL)
+ goto err_unlock;
+
+ return 0;
+
+err_unlock:
+ unlock_rename(workdir, upperdir);
+err:
+ pr_err("overlayfs: failed to lock workdir+upperdir\n");
+ return -EIO;
+}