From 16c174bd95cb07c9d0ad3fcd8c70f9cea7214c9d Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Tue, 3 Jan 2012 14:23:05 -0500 Subject: [PATCH] audit: check current inode and containing object when filtering on major and minor The audit system has the ability to filter on the major and minor number of the device containing the inode being operated upon. Lets say that /dev/sda1 has major,minor 8,1 and that we mount /dev/sda1 on /boot. Now lets say we add a watch with a filter on 8,1. If we proceed to open an inode inside /boot, such as /vboot/vmlinuz, we will match the major,minor filter. Lets instead assume that one were to use a tool like debugfs and were to open /dev/sda1 directly and to modify it's contents. We might hope that this would also be logged, but it isn't. The rules will check the major,minor of the device containing /dev/sda1. In other words the rule would match on the major/minor of the tmpfs mounted at /dev. I believe these rules should trigger on either device. The man page is devoid of useful information about the intended semantics. It only seems logical that if you want to know everything that happened on a major,minor that would include things that happened to the device itself... Signed-off-by: Eric Paris --- kernel/auditsc.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 1a92d61ddd27..7c495147c3d9 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -540,12 +540,14 @@ static int audit_filter_rules(struct task_struct *tsk, } break; case AUDIT_DEVMAJOR: - if (name) - result = audit_comparator(MAJOR(name->dev), - f->op, f->val); - else if (ctx) { + if (name) { + if (audit_comparator(MAJOR(name->dev), f->op, f->val) || + audit_comparator(MAJOR(name->rdev), f->op, f->val)) + ++result; + } else if (ctx) { list_for_each_entry(n, &ctx->names_list, list) { - if (audit_comparator(MAJOR(n->dev), f->op, f->val)) { + if (audit_comparator(MAJOR(n->dev), f->op, f->val) || + audit_comparator(MAJOR(n->rdev), f->op, f->val)) { ++result; break; } @@ -553,12 +555,14 @@ static int audit_filter_rules(struct task_struct *tsk, } break; case AUDIT_DEVMINOR: - if (name) - result = audit_comparator(MINOR(name->dev), - f->op, f->val); - else if (ctx) { + if (name) { + if (audit_comparator(MINOR(name->dev), f->op, f->val) || + audit_comparator(MINOR(name->rdev), f->op, f->val)) + ++result; + } else if (ctx) { list_for_each_entry(n, &ctx->names_list, list) { - if (audit_comparator(MINOR(n->dev), f->op, f->val)) { + if (audit_comparator(MINOR(n->dev), f->op, f->val) || + audit_comparator(MINOR(n->rdev), f->op, f->val)) { ++result; break; }