treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

12 files changed, 30 insertions, 38 deletions

diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index 7b0e13ce7dc7..f919ebd042fd 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -577,7 +577,7 @@ static struct aa_label *x_to_label(struct aa_profile *profile,
 			stack = NULL;
 			break;
 		}
-		/* fall through - to X_NAME */
+		fallthrough;	/* to X_NAME */
 	case AA_X_NAME:
 		if (xindex & AA_X_CHILD)
 			/* released by caller */
diff --git a/security/apparmor/lib.c b/security/apparmor/lib.c
index 30c246a9d440..fa49b81eb54c 100644
--- a/security/apparmor/lib.c
+++ b/security/apparmor/lib.c
@@ -292,13 +292,13 @@ void aa_apply_modes_to_perms(struct aa_profile *profile, struct aa_perms *perms)
 	switch (AUDIT_MODE(profile)) {
 	case AUDIT_ALL:
 		perms->audit = ALL_PERMS_MASK;
-		/* fall through */
+		fallthrough;
 	case AUDIT_NOQUIET:
 		perms->quiet = 0;
 		break;
 	case AUDIT_QUIET:
 		perms->audit = 0;
-		/* fall through */
+		fallthrough;
 	case AUDIT_QUIET_DENIED:
 		perms->quiet = ALL_PERMS_MASK;
 		break;
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 372d16382960..b8848f53c8cc 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -223,7 +223,7 @@ static int xattr_verify(enum ima_hooks func, struct integrity_iint_cache *iint,
 	case IMA_XATTR_DIGEST_NG:
 		/* first byte contains algorithm id */
 		hash_start = 1;
-		/* fall through */
+		fallthrough;
 	case IMA_XATTR_DIGEST:
 		if (iint->flags & IMA_DIGSIG_REQUIRED) {
 			*cause = "IMA-signature-required";
@@ -395,7 +395,7 @@ int ima_appraise_measurement(enum ima_hooks func,
 		/* It's fine not to have xattrs when using a modsig. */
 		if (try_modsig)
 			break;
-		/* fall through */
+		fallthrough;
 	case INTEGRITY_NOLABEL:		/* No security.evm xattr. */
 		cause = "missing-HMAC";
 		goto out;
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 07f033634b27..b4de33074b37 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -1279,12 +1279,12 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 		case Opt_uid_gt:
 		case Opt_euid_gt:
 			entry->uid_op = &uid_gt;
-			/* fall through */
+			fallthrough;
 		case Opt_uid_lt:
 		case Opt_euid_lt:
 			if ((token == Opt_uid_lt) || (token == Opt_euid_lt))
 				entry->uid_op = &uid_lt;
-			/* fall through */
+			fallthrough;
 		case Opt_uid_eq:
 		case Opt_euid_eq:
 			uid_token = (token == Opt_uid_eq) ||
@@ -1313,11 +1313,11 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 			break;
 		case Opt_fowner_gt:
 			entry->fowner_op = &uid_gt;
-			/* fall through */
+			fallthrough;
 		case Opt_fowner_lt:
 			if (token == Opt_fowner_lt)
 				entry->fowner_op = &uid_lt;
-			/* fall through */
+			fallthrough;
 		case Opt_fowner_eq:
 			ima_log_string_op(ab, "fowner", args[0].from,
 					  entry->fowner_op);
diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
index 41a5f435b793..c022ee9e2a4e 100644
--- a/security/integrity/ima/ima_template_lib.c
+++ b/security/integrity/ima/ima_template_lib.c
@@ -77,7 +77,7 @@ static void ima_show_template_data_ascii(struct seq_file *m,
 		/* skip ':' and '\0' */
 		buf_ptr += 2;
 		buflen -= buf_ptr - field_data->data;
-		/* fall through */
+		fallthrough;
 	case DATA_FMT_DIGEST:
 	case DATA_FMT_HEX:
 		if (!buflen)
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 7e0232db1707..1fe8b934f656 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -465,7 +465,7 @@ key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx)
 		case -EAGAIN: /* no key */
 			if (ret)
 				break;
-			/* fall through */
+			fallthrough;
 		case -ENOKEY: /* negative key */
 			ret = key_ref;
 			break;
@@ -487,7 +487,7 @@ key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx)
 		case -EAGAIN: /* no key */
 			if (ret)
 				break;
-			/* fall through */
+			fallthrough;
 		case -ENOKEY: /* negative key */
 			ret = key_ref;
 			break;
@@ -509,7 +509,7 @@ key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx)
 		case -EAGAIN: /* no key */
 			if (ret)
 				break;
-			/* fall through */
+			fallthrough;
 		case -ENOKEY: /* negative key */
 			ret = key_ref;
 			break;
diff --git a/security/keys/request_key.c b/security/keys/request_key.c
index e1b9f1a80676..2da4404276f0 100644
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -295,26 +295,26 @@ static int construct_get_dest_keyring(struct key **_dest_keyring)
 				}
 			}
 
-			/* fall through */
+			fallthrough;
 		case KEY_REQKEY_DEFL_THREAD_KEYRING:
 			dest_keyring = key_get(cred->thread_keyring);
 			if (dest_keyring)
 				break;
 
-			/* fall through */
+			fallthrough;
 		case KEY_REQKEY_DEFL_PROCESS_KEYRING:
 			dest_keyring = key_get(cred->process_keyring);
 			if (dest_keyring)
 				break;
 
-			/* fall through */
+			fallthrough;
 		case KEY_REQKEY_DEFL_SESSION_KEYRING:
 			dest_keyring = key_get(cred->session_keyring);
 
 			if (dest_keyring)
 				break;
 
-			/* fall through */
+			fallthrough;
 		case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
 			ret = look_up_user_keyrings(NULL, &dest_keyring);
 			if (ret < 0)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index ca901025802a..a340986aa92e 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3606,26 +3606,20 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd,
 
 	switch (cmd) {
 	case FIONREAD:
-	/* fall through */
 	case FIBMAP:
-	/* fall through */
 	case FIGETBSZ:
-	/* fall through */
 	case FS_IOC_GETFLAGS:
-	/* fall through */
 	case FS_IOC_GETVERSION:
 		error = file_has_perm(cred, file, FILE__GETATTR);
 		break;
 
 	case FS_IOC_SETFLAGS:
-	/* fall through */
 	case FS_IOC_SETVERSION:
 		error = file_has_perm(cred, file, FILE__SETATTR);
 		break;
 
 	/* sys_ioctl() checks */
 	case FIONBIO:
-	/* fall through */
 	case FIOASYNC:
 		error = file_has_perm(cred, file, 0);
 		break;
@@ -3783,7 +3777,7 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd,
 			err = file_has_perm(cred, file, FILE__WRITE);
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	case F_SETOWN:
 	case F_SETSIG:
 	case F_GETFL:
diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c
index 408d306895f8..d338962fb0c4 100644
--- a/security/selinux/ss/mls.c
+++ b/security/selinux/ss/mls.c
@@ -535,7 +535,7 @@ int mls_compute_sid(struct policydb *p,
 						  scontext, tcontext);
 		}
 
-		/* Fallthrough */
+		fallthrough;
 	case AVTAB_CHANGE:
 		if ((tclass == p->process_class) || sock)
 			/* Use the process MLS attributes. */
@@ -546,8 +546,6 @@ int mls_compute_sid(struct policydb *p,
 	case AVTAB_MEMBER:
 		/* Use the process effective MLS attributes. */
 		return mls_context_cpy_low(newcontext, scontext);
-
-	/* fall through */
 	}
 	return -EINVAL;
 }
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 8ffbf951b7ed..8c0893eb5aa8 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3365,7 +3365,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
 		 * to set mount options simulate setting the
 		 * superblock default.
 		 */
-		/* Fall through */
+		fallthrough;
 	default:
 		/*
 		 * This isn't an understood special case.
diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c
index c16b8c1b03e7..4bee32bfe16d 100644
--- a/security/tomoyo/common.c
+++ b/security/tomoyo/common.c
@@ -1240,7 +1240,7 @@ static bool tomoyo_print_condition(struct tomoyo_io_buffer *head,
 			tomoyo_set_space(head);
 			tomoyo_set_string(head, cond->transit->name);
 		}
-		/* fall through */
+		fallthrough;
 	case 1:
 		{
 			const u16 condc = cond->condc;
@@ -1345,12 +1345,12 @@ static bool tomoyo_print_condition(struct tomoyo_io_buffer *head,
 			}
 		}
 		head->r.cond_step++;
-		/* fall through */
+		fallthrough;
 	case 2:
 		if (!tomoyo_flush(head))
 			break;
 		head->r.cond_step++;
-		/* fall through */
+		fallthrough;
 	case 3:
 		if (cond->grant_log != TOMOYO_GRANTLOG_AUTO)
 			tomoyo_io_printf(head, " grant_log=%s",
@@ -1639,7 +1639,7 @@ static void tomoyo_read_domain(struct tomoyo_io_buffer *head)
 					tomoyo_set_string(head, tomoyo_dif[i]);
 			head->r.index = 0;
 			head->r.step++;
-			/* fall through */
+			fallthrough;
 		case 1:
 			while (head->r.index < TOMOYO_MAX_ACL_GROUPS) {
 				i = head->r.index++;
@@ -1652,14 +1652,14 @@ static void tomoyo_read_domain(struct tomoyo_io_buffer *head)
 			head->r.index = 0;
 			head->r.step++;
 			tomoyo_set_lf(head);
-			/* fall through */
+			fallthrough;
 		case 2:
 			if (!tomoyo_read_domain2(head, &domain->acl_info_list))
 				return;
 			head->r.step++;
 			if (!tomoyo_set_lf(head))
 				return;
-			/* fall through */
+			fallthrough;
 		case 3:
 			head->r.step = 0;
 			if (head->r.print_this_domain_only)
@@ -2088,7 +2088,7 @@ int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
 		/* Check max_learning_entry parameter. */
 		if (tomoyo_domain_quota_is_ok(r))
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		return 0;
 	}
@@ -2710,13 +2710,13 @@ ssize_t tomoyo_write_control(struct tomoyo_io_buffer *head,
 		case TOMOYO_DOMAINPOLICY:
 			if (tomoyo_select_domain(head, cp0))
 				continue;
-			/* fall through */
+			fallthrough;
 		case TOMOYO_EXCEPTIONPOLICY:
 			if (!strcmp(cp0, "select transition_only")) {
 				head->r.print_transition_related_only = true;
 				continue;
 			}
-			/* fall through */
+			fallthrough;
 		default:
 			if (!tomoyo_manager()) {
 				error = -EPERM;
diff --git a/security/tomoyo/file.c b/security/tomoyo/file.c
index 86f7d1b90212..051f7297877c 100644
--- a/security/tomoyo/file.c
+++ b/security/tomoyo/file.c
@@ -927,7 +927,7 @@ int tomoyo_path2_perm(const u8 operation, const struct path *path1,
 	case TOMOYO_TYPE_LINK:
 		if (!d_is_dir(path1->dentry))
 			break;
-		/* fall through */
+		fallthrough;
 	case TOMOYO_TYPE_PIVOT_ROOT:
 		tomoyo_add_slash(&buf1);
 		tomoyo_add_slash(&buf2);