3.2.44-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Linus Torvalds <[email protected]> commit 83f1b4ba917db5dc5a061a44b3403ddb6e783494 upstream. Commit 257b5358b32f ("scm: Capture the full credentials of the scm sender") changed the credentials passing code to pass in the effective uid/gid instead of the real uid/gid. Obviously this doesn't matter most of the time (since normally they are the same), but it results in differences for suid binaries when the wrong uid/gid ends up being used. This just undoes that (presumably unintentional) part of the commit. Reported-by: Andy Lutomirski <[email protected]> Cc: Eric W. Biederman <[email protected]> Cc: Serge E. Hallyn <[email protected]> Cc: David S. Miller <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Acked-by: "Eric W. Biederman" <[email protected]> Signed-off-by: David S. Miller <[email protected]> [bwh: Backported to 3.2: scm_set_cred() does user namespace conversion of euid/egid using cred_to_ucred(). Add and use cred_real_to_ucred() to do the same thing for real uid/gid.] Signed-off-by: Ben Hutchings <[email protected]> --- include/net/scm.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/include/net/scm.h +++ b/include/net/scm.h @@ -50,7 +50,7 @@ static __inline__ void scm_set_cred(stru { scm->pid = get_pid(pid); scm->cred = cred ? get_cred(cred) : NULL; - cred_to_ucred(pid, cred, &scm->creds); + cred_real_to_ucred(pid, cred, &scm->creds); } static __inline__ void scm_destroy_cred(struct scm_cookie *scm) --- a/net/core/sock.c +++ b/net/core/sock.c @@ -761,6 +761,20 @@ void cred_to_ucred(struct pid *pid, cons } EXPORT_SYMBOL_GPL(cred_to_ucred); +void cred_real_to_ucred(struct pid *pid, const struct cred *cred, + struct ucred *ucred) +{ + ucred->pid = pid_vnr(pid); + ucred->uid = ucred->gid = -1; + if (cred) { + struct user_namespace *current_ns = current_user_ns(); + + ucred->uid = user_ns_map_uid(current_ns, cred, cred->uid); + ucred->gid = user_ns_map_gid(current_ns, cred, cred->gid); + } +} +EXPORT_SYMBOL_GPL(cred_real_to_ucred); + int sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen) { --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -317,6 +317,7 @@ struct ucred { #define IPX_TYPE 1 extern void cred_to_ucred(struct pid *pid, const struct cred *cred, struct ucred *ucred); +extern void cred_real_to_ucred(struct pid *pid, const struct cred *cred, struct ucred *ucred); extern int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len); extern int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
