| Message ID | 20110517085924.3a47b8e2@kryten |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Anton Blanchard <anton@samba.org> Date: Tue, 17 May 2011 08:59:24 +1000 > > recvmmsg fails on a raw socket with EINVAL. The reason for this is > packet_recvmsg checks the incoming flags: > > err = -EINVAL; > if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE)) > goto out; > > This patch strips out MSG_WAITFORONE when calling recvmmsg which > fixes the issue. > > Signed-off-by: Anton Blanchard <anton@samba.org> > Cc: stable@kernel.org [2.6.34+] > --- > > We could also add MSG_WAITFORONE to the raw socket recvmsg check, or > just remove the check completely. Thoughts? I think both should be done. Tests like the one packet_recvmsg() is doing makes it really hard to add new MSG_* flags generically (ie. by adding the flag and having some generic socket operation all recvmsg() implementations call process that flag bit in some way). It should just explicitly check for the bits it doesn't support. And recvmmsg() should clear the bit because it is a completely internal thing. It's similar to how we hide MSG_CMSG_COMPAT from userspace. Anyways I'll apply this patch, and feel free to submit the other one. Thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Index: linux-net/net/socket.c =================================================================== --- linux-net.orig/net/socket.c 2011-05-09 08:59:22.757767314 +1000 +++ linux-net/net/socket.c 2011-05-16 17:14:52.501268819 +1000 @@ -2232,14 +2232,16 @@ int __sys_recvmmsg(int fd, struct mmsghd */ if (MSG_CMSG_COMPAT & flags) { err = __sys_recvmsg(sock, (struct msghdr __user *)compat_entry, - &msg_sys, flags, datagrams); + &msg_sys, flags & ~MSG_WAITFORONE, + datagrams); if (err < 0) break; err = __put_user(err, &compat_entry->msg_len); ++compat_entry; } else { err = __sys_recvmsg(sock, (struct msghdr __user *)entry, - &msg_sys, flags, datagrams); + &msg_sys, flags & ~MSG_WAITFORONE, + datagrams); if (err < 0) break; err = put_user(err, &entry->msg_len);
recvmmsg fails on a raw socket with EINVAL. The reason for this is packet_recvmsg checks the incoming flags: err = -EINVAL; if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE)) goto out; This patch strips out MSG_WAITFORONE when calling recvmmsg which fixes the issue. Signed-off-by: Anton Blanchard <anton@samba.org> Cc: stable@kernel.org [2.6.34+] --- We could also add MSG_WAITFORONE to the raw socket recvmsg check, or just remove the check completely. Thoughts? -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html