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author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-06 12:50:08 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-16 12:32:26 +0300 |
commit | 25ea12ec0370ad88d356e84bca5a2a0f65b1bac6 (patch) | |
tree | 312848047ac5382b486fbcee9efc44e9268bb361 | |
parent | 898fe40c6b72cce1e8fe205a7e9812548855a500 (diff) | |
download | linux-25ea12ec0370ad88d356e84bca5a2a0f65b1bac6.tar.xz |
efi: Move some sysfs files to be read-only by root
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@linux-foundation.org>
Tested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20171206095010.24170-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/firmware/efi/efi.c | 3 | ||||
-rw-r--r-- | drivers/firmware/efi/runtime-map.c | 10 | ||||
-rw-r--r-- | include/linux/sysfs.h | 6 |
3 files changed, 12 insertions, 7 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 71e090c8c85e..297066df6946 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -96,8 +96,7 @@ static ssize_t systab_show(struct kobject *kobj, 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 diff --git a/drivers/firmware/efi/runtime-map.c b/drivers/firmware/efi/runtime-map.c index 87b8e3b900d2..1df70fd4787f 100644 --- 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 kobject *kobj, struct attribute *attr, 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. diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index f97d0dbb59fa..70ceb2a14a57 100644 --- 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, \ |