From: Michael Schaller misch@google.com

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@google.com Link: https://lore.kernel.org/r/20200925074502.150448-1-misch@google.com Signed-off-by: Ard Biesheuvel ardb@kernel.org

---

This addresses an issue that breaks Ubuntu installs on platforms that have variable names as described above. One of our installers needs to sort the BootOrder to keep BootCurrent at the front, but this fails when the variable BootCurrent points at appears to not exist due to this issue.

Ref: https://bugs.launchpad.net/bugs/1899993

fs/efivarfs/super.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index 28bb5689333a..15880a68faad 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -141,6 +141,9 @@ static int efivarfs_callback(efi_char16_t *name16, efi_guid_t vendor,

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)