summaryrefslogtreecommitdiff
path: root/fs/cachefiles
diff options
context:
space:
mode:
Diffstat (limited to 'fs/cachefiles')
-rw-r--r--fs/cachefiles/xattr.c23
1 files changed, 20 insertions, 3 deletions
diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c
index 83f41bd0c3a9..35465109d9c4 100644
--- a/fs/cachefiles/xattr.c
+++ b/fs/cachefiles/xattr.c
@@ -28,6 +28,11 @@ struct cachefiles_xattr {
static const char cachefiles_xattr_cache[] =
XATTR_USER_PREFIX "CacheFiles.cache";
+struct cachefiles_vol_xattr {
+ __be32 reserved; /* Reserved, should be 0 */
+ __u8 data[]; /* netfs volume coherency data */
+} __packed;
+
/*
* set the state xattr on a cache file
*/
@@ -185,6 +190,7 @@ void cachefiles_prepare_to_write(struct fscache_cookie *cookie)
*/
bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
{
+ struct cachefiles_vol_xattr *buf;
unsigned int len = volume->vcookie->coherency_len;
const void *p = volume->vcookie->coherency;
struct dentry *dentry = volume->dentry;
@@ -192,10 +198,17 @@ bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
_enter("%x,#%d", volume->vcookie->debug_id, len);
+ len += sizeof(*buf);
+ buf = kmalloc(len, GFP_KERNEL);
+ if (!buf)
+ return false;
+ buf->reserved = cpu_to_be32(0);
+ memcpy(buf->data, p, len);
+
ret = cachefiles_inject_write_error();
if (ret == 0)
ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
- p, len, 0);
+ buf, len, 0);
if (ret < 0) {
trace_cachefiles_vfs_error(NULL, d_inode(dentry), ret,
cachefiles_trace_setxattr_error);
@@ -209,6 +222,7 @@ bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
cachefiles_coherency_vol_set_ok);
}
+ kfree(buf);
_leave(" = %d", ret);
return ret == 0;
}
@@ -218,7 +232,7 @@ bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
*/
int cachefiles_check_volume_xattr(struct cachefiles_volume *volume)
{
- struct cachefiles_xattr *buf;
+ struct cachefiles_vol_xattr *buf;
struct dentry *dentry = volume->dentry;
unsigned int len = volume->vcookie->coherency_len;
const void *p = volume->vcookie->coherency;
@@ -228,6 +242,7 @@ int cachefiles_check_volume_xattr(struct cachefiles_volume *volume)
_enter("");
+ len += sizeof(*buf);
buf = kmalloc(len, GFP_KERNEL);
if (!buf)
return -ENOMEM;
@@ -245,7 +260,9 @@ int cachefiles_check_volume_xattr(struct cachefiles_volume *volume)
"Failed to read xattr with error %zd", xlen);
}
why = cachefiles_coherency_vol_check_xattr;
- } else if (memcmp(buf->data, p, len) != 0) {
+ } else if (buf->reserved != cpu_to_be32(0)) {
+ why = cachefiles_coherency_vol_check_resv;
+ } else if (memcmp(buf->data, p, len - sizeof(*buf)) != 0) {
why = cachefiles_coherency_vol_check_cmp;
} else {
why = cachefiles_coherency_vol_check_ok;