From: Michael Schaller <misch@xxxxxxxxxx> commit 336af6a4686d885a067ecea8c3c3dd129ba4fc75 upstream. Without this patch efivarfs_alloc_dentry creates dentries with slashes in their name if the respective EFI variable has slashes in its name. This in turn causes EIO on getdents64, which prevents a complete directory listing of /sys/firmware/efi/efivars/. This patch replaces the invalid shlashes with exclamation marks like kobject_set_name_vargs does for /sys/firmware/efi/vars/ to have consistently named dentries under /sys/firmware/efi/vars/ and /sys/firmware/efi/efivars/. Signed-off-by: Michael Schaller <misch@xxxxxxxxxx> Link: https://lore.kernel.org/r/20200925074502.150448-1-misch@xxxxxxxxxx Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> Signed-off-by: dann frazier <dann.frazier@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/efivarfs/super.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -146,6 +146,9 @@ static int efivarfs_callback(efi_char16_ name[len + EFI_VARIABLE_GUID_LEN+1] = '\0'; + /* replace invalid slashes like kobject_set_name_vargs does for /sys/firmware/efi/vars. */ + strreplace(name, '/', '!'); + inode = efivarfs_get_inode(sb, d_inode(root), S_IFREG | 0644, 0, is_removable); if (!inode)