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authorLinus Torvalds <torvalds@linux-foundation.org>2016-07-03 11:57:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-07-03 11:57:09 -0700
commit236bfd8ed868edfc42a656682487683ade3fede4 (patch)
treee1311ab7ca76f663f837c7adf9aacd27492939bb
parent4f302921c1458d790ae21147f7043f4e6b6a1085 (diff)
parente7c0b5991dd1be7b6f6dc2b54a15a0f47b64b007 (diff)
Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi: "This contains fixes for a dentry leak, a regression in 4.6 noticed by Docker users and missing write access checking in truncate" * 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: warn instead of error if d_type is not supported ovl: get_write_access() in truncate ovl: fix dentry leak for default_permissions
-rw-r--r--fs/overlayfs/inode.c29
-rw-r--r--fs/overlayfs/super.c12
2 files changed, 33 insertions, 8 deletions
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 1dbeab6cf96e..c831c2e5f803 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -59,16 +59,37 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
if (err)
goto out;
+ if (attr->ia_valid & ATTR_SIZE) {
+ struct inode *realinode = d_inode(ovl_dentry_real(dentry));
+
+ err = -ETXTBSY;
+ if (atomic_read(&realinode->i_writecount) < 0)
+ goto out_drop_write;
+ }
+
err = ovl_copy_up(dentry);
if (!err) {
+ struct inode *winode = NULL;
+
upperdentry = ovl_dentry_upper(dentry);
+ if (attr->ia_valid & ATTR_SIZE) {
+ winode = d_inode(upperdentry);
+ err = get_write_access(winode);
+ if (err)
+ goto out_drop_write;
+ }
+
inode_lock(upperdentry->d_inode);
err = notify_change(upperdentry, attr, NULL);
if (!err)
ovl_copyattr(upperdentry->d_inode, dentry->d_inode);
inode_unlock(upperdentry->d_inode);
+
+ if (winode)
+ put_write_access(winode);
}
+out_drop_write:
ovl_drop_write(dentry);
out:
return err;
@@ -121,16 +142,18 @@ int ovl_permission(struct inode *inode, int mask)
err = vfs_getattr(&realpath, &stat);
if (err)
- return err;
+ goto out_dput;
+ err = -ESTALE;
if ((stat.mode ^ inode->i_mode) & S_IFMT)
- return -ESTALE;
+ goto out_dput;
inode->i_mode = stat.mode;
inode->i_uid = stat.uid;
inode->i_gid = stat.gid;
- return generic_permission(inode, mask);
+ err = generic_permission(inode, mask);
+ goto out_dput;
}
/* Careful in RCU walk mode */
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index ce02f46029da..9a7693d5f8ff 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -1082,11 +1082,13 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
if (err < 0)
goto out_put_workdir;
- if (!err) {
- pr_err("overlayfs: upper fs needs to support d_type.\n");
- err = -EINVAL;
- goto out_put_workdir;
- }
+ /*
+ * We allowed this configuration and don't want to
+ * break users over kernel upgrade. So warn instead
+ * of erroring out.
+ */
+ if (!err)
+ pr_warn("overlayfs: upper fs needs to support d_type.\n");
}
}