Commit 773e0c40 authored by David Howells's avatar David Howells
Browse files

afs: Fix afs_xattr_get_yfs() to not try freeing an error value 



afs_xattr_get_yfs() tries to free yacl, which may hold an error value (say
if yfs_fs_fetch_opaque_acl() failed and returned an error).

Fix this by allocating yacl up front (since it's a fixed-length struct,
unlike afs_acl) and passing it in to the RPC function.  This also allows
the flags to be placed in the object rather than passing them through to
the RPC function.

Fixes: ae46578b ("afs: Get YFS ACLs and information through xattrs")
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
parent cc1dd5c8

fs/afs/internal.h

+1 −1
Original line number Diff line number Diff line
@@ -1382,7 +1382,7 @@ struct yfs_acl { 
};



extern void yfs_free_opaque_acl(struct yfs_acl *);

extern struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *, unsigned int);

extern struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *, struct yfs_acl *);

extern int yfs_fs_store_opaque_acl2(struct afs_fs_cursor *, const struct afs_acl *);



/*

fs/afs/xattr.c

+46 −40
Original line number Diff line number Diff line
@@ -148,9 +148,8 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler, 
	struct afs_vnode *vnode = AFS_FS_I(inode);

	struct yfs_acl *yacl = NULL;

	struct key *key;

	unsigned int flags = 0;

	char buf[16], *data;

	int which = 0, dsize, ret;

	int which = 0, dsize, ret = -ENOMEM;



	if (strcmp(name, "acl") == 0)

		which = 0;
@@ -163,20 +162,26 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler, 
	else

		return -EOPNOTSUPP;



	yacl = kzalloc(sizeof(struct yfs_acl), GFP_KERNEL);

	if (!yacl)

		goto error;



	if (which == 0)

		flags |= YFS_ACL_WANT_ACL;

		yacl->flags |= YFS_ACL_WANT_ACL;

	else if (which == 3)

		flags |= YFS_ACL_WANT_VOL_ACL;

		yacl->flags |= YFS_ACL_WANT_VOL_ACL;



	key = afs_request_key(vnode->volume->cell);

	if (IS_ERR(key))

		return PTR_ERR(key);

	if (IS_ERR(key)) {

		ret = PTR_ERR(key);

		goto error_yacl;

	}



	ret = -ERESTARTSYS;

	if (afs_begin_vnode_operation(&fc, vnode, key)) {

		while (afs_select_fileserver(&fc)) {

			fc.cb_break = afs_calc_vnode_cb_break(vnode);

			yacl = yfs_fs_fetch_opaque_acl(&fc, flags);

			yfs_fs_fetch_opaque_acl(&fc, yacl);

		}



		afs_check_for_remote_deletion(&fc, fc.vnode);
@@ -184,7 +189,9 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler, 
		ret = afs_end_vnode_operation(&fc);

	}



	if (ret == 0) {

	if (ret < 0)

		goto error_key;



	switch (which) {

	case 0:

		data = yacl->acl->data;
@@ -192,13 +199,11 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler, 
		break;

	case 1:

		data = buf;

			dsize = snprintf(buf, sizeof(buf), "%u",

					 yacl->inherit_flag);

		dsize = snprintf(buf, sizeof(buf), "%u", yacl->inherit_flag);

		break;

	case 2:

		data = buf;

			dsize = snprintf(buf, sizeof(buf), "%u",

					 yacl->num_cleaned);

		dsize = snprintf(buf, sizeof(buf), "%u", yacl->num_cleaned);

		break;

	case 3:

		data = yacl->vol_acl->data;
@@ -206,22 +211,23 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler, 
		break;

	default:

		ret = -EOPNOTSUPP;

			goto out;

		goto error_key;

	}



	ret = dsize;

	if (size > 0) {

		if (dsize > size) {

			ret = -ERANGE;

				goto out;

			goto error_key;

		}

		memcpy(buffer, data, dsize);

	}

	}



out:

	yfs_free_opaque_acl(yacl);

error_key:

	key_put(key);

error_yacl:

	yfs_free_opaque_acl(yacl);

error:

	return ret;

}

fs/afs/yfsclient.c

+6 −23
Original line number Diff line number Diff line
@@ -2333,12 +2333,6 @@ void yfs_free_opaque_acl(struct yfs_acl *yacl) 
	}

}



static void yfs_destroy_fs_fetch_opaque_acl(struct afs_call *call)

{

	yfs_free_opaque_acl(call->reply[0]);

	afs_flat_call_destructor(call);

}



/*

 * YFS.FetchOpaqueACL operation type

 */
@@ -2346,18 +2340,17 @@ static const struct afs_call_type yfs_RXYFSFetchOpaqueACL = { 
	.name		= "YFS.FetchOpaqueACL",

	.op		= yfs_FS_FetchOpaqueACL,

	.deliver	= yfs_deliver_fs_fetch_opaque_acl,

	.destructor	= yfs_destroy_fs_fetch_opaque_acl,

	.destructor	= afs_flat_call_destructor,

};



/*

 * Fetch the YFS advanced ACLs for a file.

 */

struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *fc,

					unsigned int flags)

					struct yfs_acl *yacl)

{

	struct afs_vnode *vnode = fc->vnode;

	struct afs_call *call;

	struct yfs_acl *yacl;

	struct afs_net *net = afs_v2net(vnode);

	__be32 *bp;
@@ -2370,19 +2363,15 @@ struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *fc, 
				   sizeof(__be32) * 2 +

				   sizeof(struct yfs_xdr_YFSFetchStatus) +

				   sizeof(struct yfs_xdr_YFSVolSync));

	if (!call)

		goto nomem;



	yacl = kzalloc(sizeof(struct yfs_acl), GFP_KERNEL);

	if (!yacl)

		goto nomem_call;

	if (!call) {

		fc->ac.error = -ENOMEM;

		return ERR_PTR(-ENOMEM);

	}



	yacl->flags = flags;

	call->key = fc->key;

	call->reply[0] = yacl;

	call->reply[1] = vnode;

	call->reply[2] = NULL; /* volsync */

	call->ret_reply0 = true;



	/* marshall the parameters */

	bp = call->request;
@@ -2396,12 +2385,6 @@ struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *fc, 
	trace_afs_make_fs_call(call, &vnode->fid);

	afs_make_call(&fc->ac, call, GFP_KERNEL);

	return (struct yfs_acl *)afs_wait_for_call_to_complete(call, &fc->ac);



nomem_call:

	afs_put_call(call);

nomem:

	fc->ac.error = -ENOMEM;

	return ERR_PTR(-ENOMEM);

}



/*

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