diff options
author | Mickaël Salaün <mic@digikod.net> | 2025-05-12 11:37:30 +0200 |
---|---|---|
committer | Mickaël Salaün <mic@digikod.net> | 2025-05-12 11:38:53 +0200 |
commit | 3039ed432745f8fdf5cbb43fdc60b2e1aad624c1 (patch) | |
tree | 4dffdb52a26380ad84e43a30fcccac10bfe90a75 | |
parent | b1525d0a8d3ad98487775232c3a861f3f4d894ea (diff) | |
download | linux-next.tar.gz |
landlock: Improve bit operations in audit codelandlock-6.15-rc7next
Use the BIT() and BIT_ULL() macros in the new audit code instead of
explicit shifts to improve readability. Use bitmask instead of modulo
operation to simplify code.
Add test_range1_rand15() and test_range2_rand15() KUnit tests to improve
get_id_range() coverage.
Signed-off-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20250512093732.1408485-1-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
-rw-r--r-- | security/landlock/audit.c | 2 | ||||
-rw-r--r-- | security/landlock/id.c | 33 | ||||
-rw-r--r-- | security/landlock/syscalls.c | 3 |
3 files changed, 34 insertions, 4 deletions
diff --git a/security/landlock/audit.c b/security/landlock/audit.c index 58d5c40d4d0e1d..c52d079cdb77ba 100644 --- a/security/landlock/audit.c +++ b/security/landlock/audit.c @@ -437,7 +437,7 @@ void landlock_log_denial(const struct landlock_cred_security *const subject, return; /* Checks if the current exec was restricting itself. */ - if (subject->domain_exec & (1 << youngest_layer)) { + if (subject->domain_exec & BIT(youngest_layer)) { /* Ignores denials for the same execution. */ if (!youngest_denied->log_same_exec) return; diff --git a/security/landlock/id.c b/security/landlock/id.c index 11fab9259c157f..56f7cc0fc7440f 100644 --- a/security/landlock/id.c +++ b/security/landlock/id.c @@ -7,6 +7,7 @@ #include <kunit/test.h> #include <linux/atomic.h> +#include <linux/bitops.h> #include <linux/random.h> #include <linux/spinlock.h> @@ -25,7 +26,7 @@ static void __init init_id(atomic64_t *const counter, const u32 random_32bits) * Ensures sure 64-bit values are always used by user space (or may * fail with -EOVERFLOW), and makes this testable. */ - init = 1ULL << 32; + init = BIT_ULL(32); /* * Makes a large (2^32) boot-time value to limit ID collision in logs @@ -105,7 +106,7 @@ static u64 get_id_range(size_t number_of_ids, atomic64_t *const counter, * to get a new ID (e.g. a full landlock_restrict_self() call), and the * cost of draining all available IDs during the system's uptime. */ - random_4bits = random_4bits % (1 << 4); + random_4bits &= 0b1111; step = number_of_ids + random_4bits; /* It is safe to cast a signed atomic to an unsigned value. */ @@ -144,6 +145,19 @@ static void test_range1_rand1(struct kunit *const test) init + 2); } +static void test_range1_rand15(struct kunit *const test) +{ + atomic64_t counter; + u64 init; + + init = get_random_u32(); + atomic64_set(&counter, init); + KUNIT_EXPECT_EQ(test, get_id_range(1, &counter, 15), init); + KUNIT_EXPECT_EQ( + test, get_id_range(get_random_u8(), &counter, get_random_u8()), + init + 16); +} + static void test_range1_rand16(struct kunit *const test) { atomic64_t counter; @@ -196,6 +210,19 @@ static void test_range2_rand2(struct kunit *const test) init + 4); } +static void test_range2_rand15(struct kunit *const test) +{ + atomic64_t counter; + u64 init; + + init = get_random_u32(); + atomic64_set(&counter, init); + KUNIT_EXPECT_EQ(test, get_id_range(2, &counter, 15), init); + KUNIT_EXPECT_EQ( + test, get_id_range(get_random_u8(), &counter, get_random_u8()), + init + 17); +} + static void test_range2_rand16(struct kunit *const test) { atomic64_t counter; @@ -232,10 +259,12 @@ static struct kunit_case __refdata test_cases[] = { KUNIT_CASE(test_init_once), KUNIT_CASE(test_range1_rand0), KUNIT_CASE(test_range1_rand1), + KUNIT_CASE(test_range1_rand15), KUNIT_CASE(test_range1_rand16), KUNIT_CASE(test_range2_rand0), KUNIT_CASE(test_range2_rand1), KUNIT_CASE(test_range2_rand2), + KUNIT_CASE(test_range2_rand15), KUNIT_CASE(test_range2_rand16), {} /* clang-format on */ diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c index b9561e3417aecb..33eafb71e4f31b 100644 --- a/security/landlock/syscalls.c +++ b/security/landlock/syscalls.c @@ -9,6 +9,7 @@ #include <asm/current.h> #include <linux/anon_inodes.h> +#include <linux/bitops.h> #include <linux/build_bug.h> #include <linux/capability.h> #include <linux/cleanup.h> @@ -563,7 +564,7 @@ SYSCALL_DEFINE2(landlock_restrict_self, const int, ruleset_fd, const __u32, new_llcred->domain = new_dom; #ifdef CONFIG_AUDIT - new_llcred->domain_exec |= 1 << (new_dom->num_layers - 1); + new_llcred->domain_exec |= BIT(new_dom->num_layers - 1); #endif /* CONFIG_AUDIT */ return commit_creds(new_cred); |