diff options
Diffstat (limited to 'fs/cachefiles/xattr.c')
| -rw-r--r-- | fs/cachefiles/xattr.c | 73 |
1 files changed, 59 insertions, 14 deletions
diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c index 83f41bd0c3a9..52383b1d0ba6 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 */ @@ -59,13 +64,20 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object) memcpy(buf->data, fscache_get_aux(object->cookie), len); ret = cachefiles_inject_write_error(); - if (ret == 0) - ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache, - buf, sizeof(struct cachefiles_xattr) + len, 0); + if (ret == 0) { + ret = mnt_want_write_file(file); + if (ret == 0) { + ret = vfs_setxattr(&nop_mnt_idmap, dentry, + cachefiles_xattr_cache, buf, + sizeof(struct cachefiles_xattr) + len, 0); + mnt_drop_write_file(file); + } + } if (ret < 0) { trace_cachefiles_vfs_error(object, file_inode(file), ret, cachefiles_trace_setxattr_error); trace_cachefiles_coherency(object, file_inode(file)->i_ino, + be64_to_cpup((__be64 *)buf->data), buf->content, cachefiles_coherency_set_fail); if (ret != -ENOMEM) @@ -74,6 +86,7 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object) "Failed to set xattr with error %d", ret); } else { trace_cachefiles_coherency(object, file_inode(file)->i_ino, + be64_to_cpup((__be64 *)buf->data), buf->content, cachefiles_coherency_set_ok); } @@ -103,17 +116,22 @@ int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file xlen = cachefiles_inject_read_error(); if (xlen == 0) - xlen = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, buf, tlen); + xlen = vfs_getxattr(&nop_mnt_idmap, dentry, cachefiles_xattr_cache, buf, tlen); if (xlen != tlen) { - if (xlen < 0) + if (xlen < 0) { + ret = xlen; trace_cachefiles_vfs_error(object, file_inode(file), xlen, cachefiles_trace_getxattr_error); + } if (xlen == -EIO) cachefiles_io_error_obj( object, "Failed to read aux with error %zd", xlen); why = cachefiles_coherency_check_xattr; - } else if (buf->type != CACHEFILES_COOKIE_TYPE_DATA) { + goto out; + } + + if (buf->type != CACHEFILES_COOKIE_TYPE_DATA) { why = cachefiles_coherency_check_type; } else if (memcmp(buf->data, p, len) != 0) { why = cachefiles_coherency_check_aux; @@ -128,7 +146,9 @@ int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file ret = 0; } +out: trace_cachefiles_coherency(object, file_inode(file)->i_ino, + be64_to_cpup((__be64 *)buf->data), buf->content, why); kfree(buf); return ret; @@ -144,8 +164,14 @@ int cachefiles_remove_object_xattr(struct cachefiles_cache *cache, int ret; ret = cachefiles_inject_remove_error(); - if (ret == 0) - ret = vfs_removexattr(&init_user_ns, dentry, cachefiles_xattr_cache); + if (ret == 0) { + ret = mnt_want_write(cache->mnt); + if (ret == 0) { + ret = vfs_removexattr(&nop_mnt_idmap, dentry, + cachefiles_xattr_cache); + mnt_drop_write(cache->mnt); + } + } if (ret < 0) { trace_cachefiles_vfs_error(object, d_inode(dentry), ret, cachefiles_trace_remxattr_error); @@ -185,6 +211,7 @@ 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 +219,23 @@ 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, volume->vcookie->coherency_len); + ret = cachefiles_inject_write_error(); - if (ret == 0) - ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache, - p, len, 0); + if (ret == 0) { + ret = mnt_want_write(volume->cache->mnt); + if (ret == 0) { + ret = vfs_setxattr(&nop_mnt_idmap, dentry, + cachefiles_xattr_cache, + buf, len, 0); + mnt_drop_write(volume->cache->mnt); + } + } if (ret < 0) { trace_cachefiles_vfs_error(NULL, d_inode(dentry), ret, cachefiles_trace_setxattr_error); @@ -209,6 +249,7 @@ bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume) cachefiles_coherency_vol_set_ok); } + kfree(buf); _leave(" = %d", ret); return ret == 0; } @@ -218,7 +259,7 @@ 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; @@ -228,15 +269,17 @@ int cachefiles_check_volume_xattr(struct cachefiles_volume *volume) _enter(""); + len += sizeof(*buf); buf = kmalloc(len, GFP_KERNEL); if (!buf) return -ENOMEM; xlen = cachefiles_inject_read_error(); if (xlen == 0) - xlen = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, buf, len); + xlen = vfs_getxattr(&nop_mnt_idmap, dentry, cachefiles_xattr_cache, buf, len); if (xlen != len) { if (xlen < 0) { + ret = xlen; trace_cachefiles_vfs_error(NULL, d_inode(dentry), xlen, cachefiles_trace_getxattr_error); if (xlen == -EIO) @@ -245,7 +288,9 @@ 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; |
