When building the kernel with clang, the compiler fails to build
security/apparmor/crypto.c with the following error:
security/apparmor/crypto.c:36:8: error: fields must have a constant
size: 'variable length array in structure' extension will never be
supported
char ctx[crypto_shash_descsize(apparmor_tfm)];
^
Since commit a0a77af141 ("crypto: LLVMLinux: Add macro to remove use
of VLAIS in crypto code"), include/crypto/hash.h defines
SHASH_DESC_ON_STACK to work around this issue. Use it in aa_calc_hash()
and aa_calc_profile_hash().
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Store loaded policy and allow introspecting it through apparmorfs. This
has several uses from debugging, policy validation, and policy checkpoint
and restore for containers.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The newly added Kconfig option could never work and just causes a build error
when disabled:
security/apparmor/lsm.c:675:25: error: 'CONFIG_SECURITY_APPARMOR_HASH_DEFAULT' undeclared here (not in a function)
bool aa_g_hash_policy = CONFIG_SECURITY_APPARMOR_HASH_DEFAULT;
The problem is that the macro undefined in this case, and we need to use the IS_ENABLED()
helper to turn it into a boolean constant.
Another minor problem with the original patch is that the option is even offered
in sysfs when SECURITY_APPARMOR_HASH is not enabled, so this also hides the option
in that case.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 6059f71f1e ("apparmor: add parameter to control whether policy hashing is used")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Use the shash interface, rather than the hash interface, when hashing
AppArmor profiles. The shash interface does not use scatterlists and it
is a better fit for what AppArmor needs.
This fixes a kernel paging BUG when aa_calc_profile_hash() is passed a
buffer from vmalloc(). The hash interface requires callers to handle
vmalloc() buffers differently than what AppArmor was doing. Due to
vmalloc() memory not being physically contiguous, each individual page
behind the buffer must be assigned to a scatterlist with sg_set_page()
and then the scatterlist passed to crypto_hash_update().
The shash interface does not have that limitation and allows vmalloc()
and kmalloc() buffers to be handled in the same manner.
BugLink: https://launchpad.net/bugs/1216294/
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=62261
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Provide userspace the ability to introspect a sha1 hash value for each
profile currently loaded.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
