From 699c1868a743f530081f429058616a2dd5d8a4b2 Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Mon, 8 Apr 2019 12:50:57 -0400 Subject: [PATCH] audit: purge unnecessary list_empty calls The original conditions that led to the use of list_empty() to optimize list_for_each_entry_rcu() in auditfilter.c and auditsc.c code have been removed without removing the list_empty() call, but this code example has been copied several times. Remove the unnecessary list_empty() calls. Please see upstream github issue https://github.com/linux-audit/audit-kernel/issues/112 Signed-off-by: Richard Guy Briggs Signed-off-by: Paul Moore --- kernel/auditfilter.c | 2 -- kernel/auditsc.c | 60 ++++++++++++++++++-------------------------- 2 files changed, 25 insertions(+), 37 deletions(-) diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 63f8b3f26fab..2c3c2f349b23 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -1315,8 +1315,6 @@ int audit_filter(int msgtype, unsigned int listtype) int ret = 1; /* Audit by default */ rcu_read_lock(); - if (list_empty(&audit_filter_list[listtype])) - goto unlock_and_return; list_for_each_entry_rcu(e, &audit_filter_list[listtype], list) { int i, result = 0; diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 98a98e6dca05..51a2ceb3a1ca 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -771,15 +771,13 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk, return AUDIT_DISABLED; rcu_read_lock(); - if (!list_empty(list)) { - list_for_each_entry_rcu(e, list, list) { - if (audit_in_mask(&e->rule, ctx->major) && - audit_filter_rules(tsk, &e->rule, ctx, NULL, - &state, false)) { - rcu_read_unlock(); - ctx->current_state = state; - return state; - } + list_for_each_entry_rcu(e, list, list) { + if (audit_in_mask(&e->rule, ctx->major) && + audit_filter_rules(tsk, &e->rule, ctx, NULL, + &state, false)) { + rcu_read_unlock(); + ctx->current_state = state; + return state; } } rcu_read_unlock(); @@ -798,9 +796,6 @@ static int audit_filter_inode_name(struct task_struct *tsk, struct audit_entry *e; enum audit_state state; - if (list_empty(list)) - return 0; - list_for_each_entry_rcu(e, list, list) { if (audit_in_mask(&e->rule, ctx->major) && audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { @@ -808,7 +803,6 @@ static int audit_filter_inode_name(struct task_struct *tsk, return 1; } } - return 0; } @@ -1945,18 +1939,16 @@ void __audit_inode(struct filename *name, const struct dentry *dentry, return; rcu_read_lock(); - if (!list_empty(list)) { - list_for_each_entry_rcu(e, list, list) { - for (i = 0; i < e->rule.field_count; i++) { - struct audit_field *f = &e->rule.fields[i]; + list_for_each_entry_rcu(e, list, list) { + for (i = 0; i < e->rule.field_count; i++) { + struct audit_field *f = &e->rule.fields[i]; - if (f->type == AUDIT_FSTYPE - && audit_comparator(inode->i_sb->s_magic, - f->op, f->val) - && e->rule.action == AUDIT_NEVER) { - rcu_read_unlock(); - return; - } + if (f->type == AUDIT_FSTYPE + && audit_comparator(inode->i_sb->s_magic, + f->op, f->val) + && e->rule.action == AUDIT_NEVER) { + rcu_read_unlock(); + return; } } } @@ -2065,18 +2057,16 @@ void __audit_inode_child(struct inode *parent, return; rcu_read_lock(); - if (!list_empty(list)) { - list_for_each_entry_rcu(e, list, list) { - for (i = 0; i < e->rule.field_count; i++) { - struct audit_field *f = &e->rule.fields[i]; + list_for_each_entry_rcu(e, list, list) { + for (i = 0; i < e->rule.field_count; i++) { + struct audit_field *f = &e->rule.fields[i]; - if (f->type == AUDIT_FSTYPE - && audit_comparator(parent->i_sb->s_magic, - f->op, f->val) - && e->rule.action == AUDIT_NEVER) { - rcu_read_unlock(); - return; - } + if (f->type == AUDIT_FSTYPE + && audit_comparator(parent->i_sb->s_magic, + f->op, f->val) + && e->rule.action == AUDIT_NEVER) { + rcu_read_unlock(); + return; } } }