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: ae46578b96 ("afs: Get YFS ACLs and information through xattrs")
Signed-off-by: David Howells <dhowells@redhat.com>
This commit is contained in:
David Howells 2019-05-12 08:31:23 +01:00
parent cc1dd5c85c
commit 773e0c4025
3 changed files with 54 additions and 65 deletions

View File

@ -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 *);
/*

View File

@ -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;
}

View File

@ -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;
if (!call) {
fc->ac.error = -ENOMEM;
return ERR_PTR(-ENOMEM);
}
yacl = kzalloc(sizeof(struct yfs_acl), GFP_KERNEL);
if (!yacl)
goto nomem_call;
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);
}
/*