3.16.55-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> commit af97a77bc01ce49a466f9d4c0125479e2e2230b6 upstream. Thanks to the scripts/leaking_addresses.pl script, it was found that some EFI values should not be readable by non-root users. So make them root-only, and to do that, add a __ATTR_RO_MODE() macro to make this easier, and use it in other places at the same time. Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Tested-by: Dave Young <dyoung@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: linux-efi@xxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/20171206095010.24170-2-ard.biesheuvel@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> [bwh: Backported to 3.16: drop changes in esrt.c] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -72,8 +72,7 @@ static ssize_t systab_show(struct kobjec return str - buf; } -static struct kobj_attribute efi_attr_systab = - __ATTR(systab, 0400, systab_show, NULL); +static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400); #define EFI_FIELD(var) efi.var --- a/drivers/firmware/efi/runtime-map.c +++ b/drivers/firmware/efi/runtime-map.c @@ -67,11 +67,11 @@ static ssize_t map_attr_show(struct kobj return map_attr->show(entry, buf); } -static struct map_attribute map_type_attr = __ATTR_RO(type); -static struct map_attribute map_phys_addr_attr = __ATTR_RO(phys_addr); -static struct map_attribute map_virt_addr_attr = __ATTR_RO(virt_addr); -static struct map_attribute map_num_pages_attr = __ATTR_RO(num_pages); -static struct map_attribute map_attribute_attr = __ATTR_RO(attribute); +static struct map_attribute map_type_attr = __ATTR_RO_MODE(type, 0400); +static struct map_attribute map_phys_addr_attr = __ATTR_RO_MODE(phys_addr, 0400); +static struct map_attribute map_virt_addr_attr = __ATTR_RO_MODE(virt_addr, 0400); +static struct map_attribute map_num_pages_attr = __ATTR_RO_MODE(num_pages, 0400); +static struct map_attribute map_attribute_attr = __ATTR_RO_MODE(attribute, 0400); /* * These are default attributes that are added for every memmap entry. --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -82,6 +82,12 @@ struct attribute_group { .show = _name##_show, \ } +#define __ATTR_RO_MODE(_name, _mode) { \ + .attr = { .name = __stringify(_name), \ + .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \ + .show = _name##_show, \ +} + #define __ATTR_WO(_name) { \ .attr = { .name = __stringify(_name), .mode = S_IWUSR }, \ .store = _name##_store, \