[PATCH 2.6.19-rc4] audit: support for descriptor pairs (fwd)

Mark Workman
2006-11-07T13:18:57Z

---------- Forwarded message ----------
Date: Fri, 3 Nov 2006 14:22:39 -0500 (EST)
From: Mark Workman <mworkman@linus.mitre.org>
To: sgrubb@redhat.com
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH 2.6.19-rc4] audit: support for descriptor pairs

provide an audit record of the descriptor pair returned by pipe() and
socketpair().

Signed-off-by: Jeremy Latt <jlatt@faceprint.com>
Signed-off-by: Steven Trieber <spt@mitre.org>
Signed-off-by: Mark Workman <mworkman@mitre.org>

---
fs/pipe.c | 7 ++++++
include/linux/audit.h | 9 ++++++++
kernel/auditsc.c | 40 ++++++++++++++++++++++++++++++++++++
net/socket.c | 55 +++++++++++++++++++++++++++++++++++++++-----------
4 files changed, 99 insertions(+), 12 deletions(-)
---
diff -uprN -X a/Documentation/dontdiff a/fs/pipe.c b/fs/pipe.c
--- a/fs/pipe.c 2006-10-31 16:03:48.000000000 -0500
+++ b/fs/pipe.c 2006-10-31 16:10:50.000000000 -0500
@@ -16,6 +16,7 @@
#include <linux/uio.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
+#include <linux/audit.h>

#include <asm/uaccess.h>
#include <asm/ioctls.h>
@@ -972,6 +973,10 @@ int do_pipe(int *fd)
goto err_fdr;
fdw = error;

+ error = audit_fd_pair(fdr, fdw);
+ if (error < 0)
+ goto err_fdw;
+
fd_install(fdr, fr);
fd_install(fdw, fw);
fd[0] = fdr;
@@ -979,6 +984,8 @@ int do_pipe(int *fd)

return 0;

+ err_fdw:
+ put_unused_fd(fdw);
err_fdr:
put_unused_fd(fdr);
err_read_pipe:
diff -uprN -X a/Documentation/dontdiff a/include/linux/audit.h b/include/linux/audit.h
--- a/include/linux/audit.h 2006-10-31 16:03:48.000000000 -0500
+++ b/include/linux/audit.h 2006-10-31 16:10:50.000000000 -0500
@@ -89,6 +89,7 @@
#define AUDIT_MQ_NOTIFY 1314 /* POSIX MQ notify record type */
#define AUDIT_MQ_GETSETATTR 1315 /* POSIX MQ get/set attribute record type */
#define AUDIT_KERNEL_OTHER 1316 /* For use by 3rd party modules */
+#define AUDIT_FD_PAIR 1317 /* audit record for pipe/socketpair */

#define AUDIT_AVC 1400 /* SE Linux avc denial or grant */
#define AUDIT_SELINUX_ERR 1401 /* Internal SE Linux Errors */
@@ -382,6 +383,7 @@ extern int __audit_ipc_set_perm(unsigned
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);
@@ -396,6 +398,12 @@ static inline int audit_ipc_obj(struct k
return __audit_ipc_obj(ipcp);
return 0;
}
+static inline int audit_fd_pair(int fd1, int fd2)
+{
+ if (unlikely(!audit_dummy_context()))
+ return __audit_fd_pair(fd1, fd2);
+ return 0;
+}
static inline int audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
{
if (unlikely(!audit_dummy_context()))
@@ -453,6 +461,7 @@ extern int audit_n_rules;
#define audit_ipc_set_perm(q,u,g,m) ({ 0; })
#define audit_bprm(p) ({ 0; })
#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)
diff -uprN -X a/Documentation/dontdiff a/kernel/auditsc.c b/kernel/auditsc.c
--- a/kernel/auditsc.c 2006-10-31 16:03:48.000000000 -0500
+++ b/kernel/auditsc.c 2006-10-31 16:10:50.000000000 -0500
@@ -169,6 +169,11 @@ struct audit_aux_data_sockaddr {
char a[0];
};

+struct audit_aux_data_fd_pair {
+ struct audit_aux_data d;
+ int fd[2];
+};
+
struct audit_aux_data_path {
struct audit_aux_data d;
struct dentry *dentry;
@@ -956,6 +961,11 @@ static void audit_log_exit(struct audit_
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]);
+ break; }
+
}
audit_log_end(ab);
}
@@ -1808,6 +1818,36 @@ int audit_socketcall(int nargs, unsigned
}

/**
+ * __audit_fd_pair - record audit data for pipe and socketpair
+ * @fd1: the first file descriptor
+ * @fd2: the second file descriptor
+ *
+ * Returns 0 for success or NULL context or < 0 on error.
+ */
+int __audit_fd_pair(int fd1, int fd2)
+{
+ struct audit_context *context = current->audit_context;
+ struct audit_aux_data_fd_pair *ax;
+
+ if (likely(!context)) {
+ return 0;
+ }
+
+ ax = kmalloc(sizeof(*ax), GFP_KERNEL);
+ if (!ax) {
+ return -ENOMEM;
+ }
+
+ ax->fd[0] = fd1;
+ ax->fd[1] = fd2;
+
+ ax->d.type = AUDIT_FD_PAIR;
+ ax->d.next = context->aux;
+ context->aux = (void *)ax;
+ return 0;
+}
+
+/**
* audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
* @len: data length in user space
* @a: data address in kernel space
diff -uprN -X a/Documentation/dontdiff a/net/socket.c b/net/socket.c
--- a/net/socket.c 2006-10-31 16:03:49.000000000 -0500
+++ b/net/socket.c 2006-11-03 14:19:46.000000000 -0500
@@ -393,6 +393,47 @@ int sock_map_fd(struct socket *sock)
return fd;
}

+int sock_map_fd_pair(struct socket *sock1, struct socket *sock2, int *fd1, int *fd2)
+{
+ int err;
+ struct file *newfile1;
+ struct file *newfile2;
+
+ *fd1 = err = sock_alloc_fd(&newfile1);
+ if (unlikely(*fd1 < 0))
+ return err;
+
+ err = sock_attach_fd(sock1, newfile1);
+ if (unlikely(err < 0))
+ goto err_f1;
+
+ *fd2 = err = sock_alloc_fd(&newfile2);
+ if (unlikely(*fd2 < 0))
+ goto err_f1;
+
+ err = sock_attach_fd(sock2, newfile2);
+ if (unlikely(err < 0))
+ goto err_f2;
+
+ err = audit_fd_pair(*fd1, *fd2);
+ if (err < 0)
+ goto err_f2;
+
+ fd_install(*fd1, newfile1);
+ fd_install(*fd2, newfile2);
+
+ return 0;
+
+err_f2:
+ fput(newfile2);
+ put_unused_fd(*fd2);
+
+err_f1:
+ fput(newfile1);
+ put_unused_fd(*fd1);
+ return (err);
+}
+
static struct socket *sock_from_file(struct file *file, int *err)
{
struct inode *inode;
@@ -1220,15 +1261,9 @@ asmlinkage long sys_socketpair(int famil

fd1 = fd2 = -1;

- err = sock_map_fd(sock1);
+ err = sock_map_fd_pair(sock1, sock2, &fd1, &fd2);
if (err < 0)
goto out_release_both;
- fd1 = err;
-
- err = sock_map_fd(sock2);
- if (err < 0)
- goto out_close_1;
- fd2 = err;

/* fd1 and fd2 may be already another descriptors.
* Not kernel problem.
@@ -1244,11 +1279,6 @@ asmlinkage long sys_socketpair(int famil
sys_close(fd1);
return err;

-out_close_1:
- sock_release(sock2);
- sys_close(fd1);
- return err;
-
out_release_both:
sock_release(sock2);
out_release_1:
@@ -2259,6 +2289,7 @@ EXPORT_SYMBOL(sock_create);
EXPORT_SYMBOL(sock_create_kern);
EXPORT_SYMBOL(sock_create_lite);
EXPORT_SYMBOL(sock_map_fd);
+EXPORT_SYMBOL(sock_map_fd_pair);
EXPORT_SYMBOL(sock_recvmsg);
EXPORT_SYMBOL(sock_register);
EXPORT_SYMBOL(sock_release);