From a2c6983740104c8e608c411eff6a58e2f4feaede Mon Sep 17 00:00:00 2001 From: AKASHI Takahiro Date: Fri, 24 May 2019 15:59:03 +0900 Subject: [PATCH] efi_loader: variable: attributes may not be changed if a variable exists If a variable already exists, efi_set_variable() should not change the variable's attributes. This patch enforces it. Signed-off-by: AKASHI Takahiro Reviewed-by: Heinrich Schuchardt --- lib/efi_loader/efi_variable.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c index 0d973773fa..50bc10537f 100644 --- a/lib/efi_loader/efi_variable.c +++ b/lib/efi_loader/efi_variable.c @@ -451,12 +451,21 @@ efi_status_t EFIAPI efi_set_variable(u16 *variable_name, if (val) { parse_attr(val, &attr); + /* We should not free val */ + val = NULL; if (attr & READ_ONLY) { - /* We should not free val */ - val = NULL; ret = EFI_WRITE_PROTECTED; goto out; } + + /* + * attributes won't be changed + * TODO: take care of APPEND_WRITE once supported + */ + if (attr != attributes) { + ret = EFI_INVALID_PARAMETER; + goto out; + } } val = malloc(2 * data_size + strlen("{ro,run,boot}(blob)") + 1); -- 2.25.1