cachefiles: propagate errors from vfs_getxattr() to avoid infinite loop

In cachefiles_check_volume_xattr(), the error returned by vfs_getxattr()
is not passed to ret, so it ends up returning -ESTALE, which leads to an
endless loop as follows:

cachefiles_acquire_volume
retry:
  ret = cachefiles_check_volume_xattr
    ret = -ESTALE
    xlen = vfs_getxattr // return -EIO
    // The ret is not updated when xlen < 0, so -ESTALE is returned.
    return ret
  // Supposed to jump out of the loop at this judgement.
  if (ret != -ESTALE)
      goto error_dir;
  cachefiles_bury_object
    //  EIO causes rename failure
  goto retry;

Hence propagate the error returned by vfs_getxattr() to avoid the above
issue. Do the same in cachefiles_check_auxdata().

Fixes: 32e150037d ("fscache, cachefiles: Store the volume coherency data")
Fixes: 72b957856b ("cachefiles: Implement metadata/coherency data storage in xattrs")
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240628062930.2467993-5-libaokun@huaweicloud.com
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Baokun Li 2024-06-28 14:29:25 +08:00 committed by Christian Brauner
parent 5d8f805789
commit 0ece614a52

View File

@ -110,9 +110,11 @@ int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file
if (xlen == 0)
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,
@ -252,6 +254,7 @@ int cachefiles_check_volume_xattr(struct cachefiles_volume *volume)
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)