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| author | Catherine Zhang <cxzhang@watson.ibm.com> | 2006-08-02 14:12:06 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2006-08-02 14:12:06 -0700 |
| commit | dc49c1f94e3469d94b952e8f5160dd4ccd791d79 (patch) | |
| tree | e47b1974c262a03dbabf0a148325d9089817e78e /net | |
| parent | 2b7e24b66d31d677d76b49918e711eb360c978b6 (diff) | |
| download | linux-dc49c1f94e3469d94b952e8f5160dd4ccd791d79.tar.gz | |
[AF_UNIX]: Kernel memory leak fix for af_unix datagram getpeersec patch
From: Catherine Zhang <cxzhang@watson.ibm.com> This patch implements a cleaner fix for the memory leak problem of the original unix datagram getpeersec patch. Instead of creating a security context each time a unix datagram is sent, we only create the security context when the receiver requests it. This new design requires modification of the current unix_getsecpeer_dgram LSM hook and addition of two new hooks, namely, secid_to_secctx and release_secctx. The former retrieves the security context and the latter releases it. A hook is required for releasing the security context because it is up to the security module to decide how that's done. In the case of Selinux, it's a simple kfree operation. Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/ip_sockglue.c | 9 | ||||
| -rw-r--r-- | net/unix/af_unix.c | 17 |
2 files changed, 12 insertions, 14 deletions
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 84f43a3c9098..2d05c4133d3e 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -112,14 +112,19 @@ static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb) static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb) { char *secdata; - u32 seclen; + u32 seclen, secid; int err; - err = security_socket_getpeersec_dgram(skb, &secdata, &seclen); + err = security_socket_getpeersec_dgram(NULL, skb, &secid); + if (err) + return; + + err = security_secid_to_secctx(secid, &secdata, &seclen); if (err) return; put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata); + security_release_secctx(secdata, seclen); } diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 6f2909279268..de6ec519272e 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -128,23 +128,17 @@ static atomic_t unix_nr_socks = ATOMIC_INIT(0); #define UNIX_ABSTRACT(sk) (unix_sk(sk)->addr->hash != UNIX_HASH_SIZE) #ifdef CONFIG_SECURITY_NETWORK -static void unix_get_peersec_dgram(struct sk_buff *skb) +static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) { - int err; - - err = security_socket_getpeersec_dgram(skb, UNIXSECDATA(skb), - UNIXSECLEN(skb)); - if (err) - *(UNIXSECDATA(skb)) = NULL; + memcpy(UNIXSID(skb), &scm->secid, sizeof(u32)); } static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) { - scm->secdata = *UNIXSECDATA(skb); - scm->seclen = *UNIXSECLEN(skb); + scm->secid = *UNIXSID(skb); } #else -static inline void unix_get_peersec_dgram(struct sk_buff *skb) +static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) { } static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) @@ -1322,8 +1316,7 @@ static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, memcpy(UNIXCREDS(skb), &siocb->scm->creds, sizeof(struct ucred)); if (siocb->scm->fp) unix_attach_fds(siocb->scm, skb); - - unix_get_peersec_dgram(skb); + unix_get_secdata(siocb->scm, skb); skb->h.raw = skb->data; err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len); |