[PATCH] get rid of AVC_PATH postponed treatment

        Selinux folks had been complaining about the lack of AVC_PATH
records when audit is disabled.  I must admit my stupidity - I assumed
that avc_audit() really couldn't use audit_log_d_path() because of
deadlocks (== could be called with dcache_lock or vfsmount_lock held).
Shouldn't have made that assumption - it never gets called that way.
It _is_ called under spinlocks, but not those.

        Since audit_log_d_path() uses ab->gfp_mask for allocations,
kmalloc() in there is not a problem.  IOW, the simple fix is sufficient:
let's rip AUDIT_AVC_PATH out and simply generate pathname as part of main
record.  It's trivial to do.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: James Morris <jmorris@namei.org>

diff --git a/include/linux/audit.h b/include/linux/audit.h
index a35859a..4bbd860 100644 (file)
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -411,7 +411,6 @@ extern int audit_bprm(struct linux_binprm *bprm);
 extern int audit_socketcall(int nargs, unsigned long *args);
 extern int audit_sockaddr(int len, void *addr);
 extern int __audit_fd_pair(int fd1, int fd2);
-extern int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt);
 extern int audit_set_macxattr(const char *name);
 extern int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr);
 extern int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, const struct timespec __user *u_abs_timeout);
@@ -491,7 +490,6 @@ extern int audit_signals;
 #define audit_socketcall(n,a) ({ 0; })
 #define audit_fd_pair(n,a) ({ 0; })
 #define audit_sockaddr(len, addr) ({ 0; })
-#define audit_avc_path(dentry, mnt) ({ 0; })
 #define audit_set_macxattr(n) do { ; } while (0)
 #define audit_mq_open(o,m,a) ({ 0; })
 #define audit_mq_timedsend(d,l,p,t) ({ 0; })

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index f5e917e..bde1124 100644 (file)
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -173,12 +173,6 @@ struct audit_aux_data_fd_pair {
        int     fd[2];
 };
 
-struct audit_aux_data_path {
-       struct audit_aux_data   d;
-       struct dentry           *dentry;
-       struct vfsmount         *mnt;
-};
-
 struct audit_aux_data_pids {
        struct audit_aux_data   d;
        pid_t                   target_pid[AUDIT_AUX_PIDS];
@@ -654,12 +648,6 @@ static inline void audit_free_aux(struct audit_context *context)
        struct audit_aux_data *aux;
 
        while ((aux = context->aux)) {
-               if (aux->type == AUDIT_AVC_PATH) {
-                       struct audit_aux_data_path *axi = (void *)aux;
-                       dput(axi->dentry);
-                       mntput(axi->mnt);
-               }
-
                context->aux = aux->next;
                kfree(aux);
        }
@@ -1038,11 +1026,6 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
                        audit_log_hex(ab, axs->a, axs->len);
                        break; }
 
-               case AUDIT_AVC_PATH: {
-                       struct audit_aux_data_path *axi = (void *)aux;
-                       audit_log_d_path(ab, "path=", axi->dentry, axi->mnt);
-                       break; }
-
                case AUDIT_FD_PAIR: {
                        struct audit_aux_data_fd_pair *axs = (void *)aux;
                        audit_log_format(ab, "fd0=%d fd1=%d", axs->fd[0], axs->fd[1]);
@@ -1991,36 +1974,6 @@ void __audit_ptrace(struct task_struct *t)
 }
 
 /**
- * audit_avc_path - record the granting or denial of permissions
- * @dentry: dentry to record
- * @mnt: mnt to record
- *
- * Returns 0 for success or NULL context or < 0 on error.
- *
- * Called from security/selinux/avc.c::avc_audit()
- */
-int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt)
-{
-       struct audit_aux_data_path *ax;
-       struct audit_context *context = current->audit_context;
-
-       if (likely(!context))
-               return 0;
-
-       ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
-       if (!ax)
-               return -ENOMEM;
-
-       ax->dentry = dget(dentry);
-       ax->mnt = mntget(mnt);
-
-       ax->d.type = AUDIT_AVC_PATH;
-       ax->d.next = context->aux;
-       context->aux = (void *)ax;
-       return 0;
-}
-
-/**
  * audit_signal_info - record signal info for shutting down audit subsystem
  * @sig: signal value
  * @t: task being signaled

diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index ecd0673..0e69adf 100644 (file)
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -570,10 +570,12 @@ void avc_audit(u32 ssid, u32 tsid,
                case AVC_AUDIT_DATA_FS:
                        if (a->u.fs.dentry) {
                                struct dentry *dentry = a->u.fs.dentry;
-                               if (a->u.fs.mnt)
-                                       audit_avc_path(dentry, a->u.fs.mnt);
-                               audit_log_format(ab, " name=");
-                               audit_log_untrustedstring(ab, dentry->d_name.name);
+                               if (a->u.fs.mnt) {
+                                       audit_log_d_path(ab, "path=", dentry, a->u.fs.mnt);
+                               } else {
+                                       audit_log_format(ab, " name=");
+                                       audit_log_untrustedstring(ab, dentry->d_name.name);
+                               }
                                inode = dentry->d_inode;
                        } else if (a->u.fs.inode) {
                                struct dentry *dentry;
@@ -624,9 +626,8 @@ void avc_audit(u32 ssid, u32 tsid,
                                case AF_UNIX:
                                        u = unix_sk(sk);
                                        if (u->dentry) {
-                                               audit_avc_path(u->dentry, u->mnt);
-                                               audit_log_format(ab, " name=");
-                                               audit_log_untrustedstring(ab, u->dentry->d_name.name);
+                                               audit_log_d_path(ab, "path=",
+                                                                u->dentry, u->mnt);
                                                break;
                                        }
                                        if (!u->addr)