xemu/hw/9pfs/virtio-9p-xattr-user.c
Jim Meyering 9238c2099d virtio-9p: avoid unwarranted uses of strncpy
In all of these cases, the uses of strncpy were unnecessary, since
at each point of use we know that the NUL-terminated source bytes
fit in the destination buffer.  Use memcpy in place of strncpy.

Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-10-05 07:58:37 -05:00

114 lines
2.9 KiB
C

/*
* Virtio 9p user. xattr callback
*
* Copyright IBM, Corp. 2010
*
* Authors:
* Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#include <sys/types.h>
#include "hw/virtio.h"
#include "virtio-9p.h"
#include "fsdev/file-op-9p.h"
#include "virtio-9p-xattr.h"
static ssize_t mp_user_getxattr(FsContext *ctx, const char *path,
const char *name, void *value, size_t size)
{
char buffer[PATH_MAX];
if (strncmp(name, "user.virtfs.", 12) == 0) {
/*
* Don't allow fetch of user.virtfs namesapce
* in case of mapped security
*/
errno = ENOATTR;
return -1;
}
return lgetxattr(rpath(ctx, path, buffer), name, value, size);
}
static ssize_t mp_user_listxattr(FsContext *ctx, const char *path,
char *name, void *value, size_t size)
{
int name_size = strlen(name) + 1;
if (strncmp(name, "user.virtfs.", 12) == 0) {
/* check if it is a mapped posix acl */
if (strncmp(name, "user.virtfs.system.posix_acl_", 29) == 0) {
/* adjust the name and size */
name += 12;
name_size -= 12;
} else {
/*
* Don't allow fetch of user.virtfs namesapce
* in case of mapped security
*/
return 0;
}
}
if (!value) {
return name_size;
}
if (size < name_size) {
errno = ERANGE;
return -1;
}
/* name_size includes the trailing NUL. */
memcpy(value, name, name_size);
return name_size;
}
static int mp_user_setxattr(FsContext *ctx, const char *path, const char *name,
void *value, size_t size, int flags)
{
char buffer[PATH_MAX];
if (strncmp(name, "user.virtfs.", 12) == 0) {
/*
* Don't allow fetch of user.virtfs namesapce
* in case of mapped security
*/
errno = EACCES;
return -1;
}
return lsetxattr(rpath(ctx, path, buffer), name, value, size, flags);
}
static int mp_user_removexattr(FsContext *ctx,
const char *path, const char *name)
{
char buffer[PATH_MAX];
if (strncmp(name, "user.virtfs.", 12) == 0) {
/*
* Don't allow fetch of user.virtfs namesapce
* in case of mapped security
*/
errno = EACCES;
return -1;
}
return lremovexattr(rpath(ctx, path, buffer), name);
}
XattrOperations mapped_user_xattr = {
.name = "user.",
.getxattr = mp_user_getxattr,
.setxattr = mp_user_setxattr,
.listxattr = mp_user_listxattr,
.removexattr = mp_user_removexattr,
};
XattrOperations passthrough_user_xattr = {
.name = "user.",
.getxattr = pt_getxattr,
.setxattr = pt_setxattr,
.listxattr = pt_listxattr,
.removexattr = pt_removexattr,
};