ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 04:33:26 +02:00
Code Issues Packages Projects Releases Wiki Activity

xattr: break delegations in {set,remove}xattr

Browse Source 
set/removexattr on an exported filesystem should break NFS delegations.
This is true in general, but also for the upcoming support for
RFC 8726 (NFSv4 extended attribute support). Make sure that they do.

Additionally, they need to grow a _locked variant, since callers might
call this with i_rwsem held (like the NFS server code).

Cc: stable@vger.kernel.org # v4.9+
Cc: linux-fsdevel@vger.kernel.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This commit is contained in:
Frank van der Linden
2020-06-23 22:39:18 +00:00
committed by Chuck Lever
parent c132621047
commit 08b5d5014a
2 changed files with 79 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

84
fs/xattr.c
View File

@@ -204,10 +204,22 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
return error;
}
/**
* __vfs_setxattr_locked: set an extended attribute while holding the inode
* lock
*
* @dentry - object to perform setxattr on
* @name - xattr name to set
* @value - value to set @name to
* @size - size of @value
* @flags - flags to pass into filesystem operations
* @delegated_inode - on return, will contain an inode pointer that
* a delegation was broken on, NULL if none.
*/
int
vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
size_t size, int flags)
__vfs_setxattr_locked(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags,
struct inode **delegated_inode)
{
struct inode *inode = dentry->d_inode;
int error;
@@ -216,15 +228,40 @@ vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
if (error)
return error;
inode_lock(inode);
error = security_inode_setxattr(dentry, name, value, size, flags);
if (error)
goto out;
error = try_break_deleg(inode, delegated_inode);
if (error)
goto out;
error = __vfs_setxattr_noperm(dentry, name, value, size, flags);
out:
return error;
}
EXPORT_SYMBOL_GPL(__vfs_setxattr_locked);
int
vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
size_t size, int flags)
{
struct inode *inode = dentry->d_inode;
struct inode *delegated_inode = NULL;
int error;
retry_deleg:
inode_lock(inode);
error = __vfs_setxattr_locked(dentry, name, value, size, flags,
&delegated_inode);
inode_unlock(inode);
if (delegated_inode) {
error = break_deleg_wait(&delegated_inode);
if (!error)
goto retry_deleg;
}
return error;
}
EXPORT_SYMBOL_GPL(vfs_setxattr);
@@ -378,8 +415,18 @@ __vfs_removexattr(struct dentry *dentry, const char *name)
}
EXPORT_SYMBOL(__vfs_removexattr);
/**
* __vfs_removexattr_locked: set an extended attribute while holding the inode
* lock
*
* @dentry - object to perform setxattr on
* @name - name of xattr to remove
* @delegated_inode - on return, will contain an inode pointer that
* a delegation was broken on, NULL if none.
*/
int
vfs_removexattr(struct dentry *dentry, const char *name)
__vfs_removexattr_locked(struct dentry *dentry, const char *name,
struct inode **delegated_inode)
{
struct inode *inode = dentry->d_inode;
int error;
@@ -388,11 +435,14 @@ vfs_removexattr(struct dentry *dentry, const char *name)
if (error)
return error;
inode_lock(inode);
error = security_inode_removexattr(dentry, name);
if (error)
goto out;
error = try_break_deleg(inode, delegated_inode);
if (error)
goto out;
error = __vfs_removexattr(dentry, name);
if (!error) {
@@ -401,12 +451,32 @@ vfs_removexattr(struct dentry *dentry, const char *name)
}
out:
return error;
}
EXPORT_SYMBOL_GPL(__vfs_removexattr_locked);
int
vfs_removexattr(struct dentry *dentry, const char *name)
{
struct inode *inode = dentry->d_inode;
struct inode *delegated_inode = NULL;
int error;
retry_deleg:
inode_lock(inode);
error = __vfs_removexattr_locked(dentry, name, &delegated_inode);
inode_unlock(inode);
if (delegated_inode) {
error = break_deleg_wait(&delegated_inode);
if (!error)
goto retry_deleg;
}
return error;
}
EXPORT_SYMBOL_GPL(vfs_removexattr);
/*
* Extended attribute SET operations
*/