leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

PATCH] cifs: fix broken mounts when a SSH tunnel is used (try #4)

Browse Source 
One more try..

It seems there is a regression that got introduced while Jeff fixed
all the mount/umount races. While attempting to find whether a tcp
session is already existing, we were not checking whether the "port"
used are the same. When a second mount is attempted with a different
"port=" option, it is being ignored. Because of this the cifs mounts
that uses a SSH tunnel appears to be broken.

Steps to reproduce:

1. create 2 shares
# SSH Tunnel a SMB session
2. ssh -f -L 6111:127.0.0.1:445 root@localhost "sleep 86400"
3. ssh -f -L 6222:127.0.0.1:445 root@localhost "sleep 86400"
4. tcpdump -i lo 6111 &
5. mkdir -p /mnt/mnt1
6. mkdir -p /mnt/mnt2
7. mount.cifs //localhost/a /mnt/mnt1 -o username=guest,ip=127.0.0.1,port=6111
#(shows tcpdump activity on port 6111)
8. mount.cifs //localhost/b /mnt/mnt2 -o username=guest,ip=127.0.0.1,port=6222
#(shows tcpdump activity only on port 6111 and not on 6222

Fix by adding a check to compare the port _only_ if the user tries to
override the tcp port with "port=" option, before deciding that an
existing tcp session is found. Also, clean up a bit by replacing
if-else if by a switch statment while at it as suggested by Jeff.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This commit is contained in:
Suresh Jayaraman 2009-08-20 13:03:34 +05:30 committed by Steve French
parent 1b3859bc9e
commit bdb97adcdf
1 changed files with 33 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
fs/cifs/connect.c
View File

@ -1377,7 +1377,7 @@ cifs_parse_mount_options(char *options, const char *devname,
}
static struct TCP_Server_Info *
cifs_find_tcp_session(struct sockaddr_storage *addr)
cifs_find_tcp_session(struct sockaddr_storage *addr, unsigned short int port)
{
struct list_head *tmp;
struct TCP_Server_Info *server;
@ -1397,17 +1397,38 @@ cifs_find_tcp_session(struct sockaddr_storage *addr)
if (server->tcpStatus == CifsNew)
continue;
if (addr->ss_family == AF_INET &&
(addr4->sin_addr.s_addr !=
server->addr.sockAddr.sin_addr.s_addr))
switch (addr->ss_family) {
case AF_INET:
if (addr4->sin_addr.s_addr ==
server->addr.sockAddr.sin_addr.s_addr) {
addr4->sin_port = htons(port);
/* user overrode default port? */
if (addr4->sin_port) {
if (addr4->sin_port !=
server->addr.sockAddr.sin_port)
continue;
else if (addr->ss_family == AF_INET6 &&
(!ipv6_addr_equal(&server->addr.sockAddr6.sin6_addr,
&addr6->sin6_addr) ||
server->addr.sockAddr6.sin6_scope_id !=
addr6->sin6_scope_id))
}
break;
} else
continue;
case AF_INET6:
if (ipv6_addr_equal(&addr6->sin6_addr,
&server->addr.sockAddr6.sin6_addr) &&
(addr6->sin6_scope_id ==
server->addr.sockAddr6.sin6_scope_id)) {
addr6->sin6_port = htons(port);
/* user overrode default port? */
if (addr6->sin6_port) {
if (addr6->sin6_port !=
server->addr.sockAddr6.sin6_port)
continue;
}
break;
} else
continue;
}
++server->srv_count;
write_unlock(&cifs_tcp_ses_lock);
cFYI(1, ("Existing tcp session with server found"));
@ -1475,7 +1496,7 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
}
/* see if we already have a matching tcp_ses */
tcp_ses = cifs_find_tcp_session(&addr);
tcp_ses = cifs_find_tcp_session(&addr, volume_info->port);
if (tcp_ses)
return tcp_ses;