linux-toradex.git/net/bluetooth, branch v3.10.78 Linux kernel for Apalis and Colibri modules Bluetooth: Avoid use of session socket after the session gets freed 2014-09-17T16:04:00+00:00 Vignesh Raman Vignesh_Raman@mentor.com 2014-07-22T13:54:25+00:00 07b41b34490bb0286a1537afe0190bb197f973eb commit 32333edb82fb2009980eefc5518100068147ab82 upstream. The commits 08c30aca9e698faddebd34f81e1196295f9dc063 "Bluetooth: Remove RFCOMM session refcnt" and 8ff52f7d04d9cc31f1e81dcf9a2ba6335ed34905 "Bluetooth: Return RFCOMM session ptrs to avoid freed session" allow rfcomm_recv_ua and rfcomm_session_close to delete the session (and free the corresponding socket) and propagate NULL session pointer to the upper callers. Additional fix is required to terminate the loop in rfcomm_process_rx function to avoid use of freed 'sk' memory. The issue is only reproducible with kernel option CONFIG_PAGE_POISONING enabled making freed memory being changed and filled up with fixed char value used to unmask use-after-free issues. Signed-off-by: Vignesh Raman <Vignesh_Raman@mentor.com> Signed-off-by: Vitaly Kuzmichev <Vitaly_Kuzmichev@mentor.com> Acked-by: Dean Jenkins <Dean_Jenkins@mentor.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 32333edb82fb2009980eefc5518100068147ab82 upstream.

The commits 08c30aca9e698faddebd34f81e1196295f9dc063 "Bluetooth: Remove
RFCOMM session refcnt" and 8ff52f7d04d9cc31f1e81dcf9a2ba6335ed34905
"Bluetooth: Return RFCOMM session ptrs to avoid freed session"
allow rfcomm_recv_ua and rfcomm_session_close to delete the session
(and free the corresponding socket) and propagate NULL session pointer
to the upper callers.

Additional fix is required to terminate the loop in rfcomm_process_rx
function to avoid use of freed 'sk' memory.

The issue is only reproducible with kernel option CONFIG_PAGE_POISONING
enabled making freed memory being changed and filled up with fixed char
value used to unmask use-after-free issues.

Signed-off-by: Vignesh Raman <Vignesh_Raman@mentor.com>
Signed-off-by: Vitaly Kuzmichev <Vitaly_Kuzmichev@mentor.com>
Acked-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: never linger on process exit 2014-09-17T16:04:00+00:00 Vladimir Davydov vdavydov@parallels.com 2014-07-15T08:25:28+00:00 819f3e7ae9c1ad79b7f9583ea687cdcebe7a0fe1 commit 093facf3634da1b0c2cc7ed106f1983da901bbab upstream. If the current process is exiting, lingering on socket close will make it unkillable, so we should avoid it. Reproducer: #include <sys/types.h> #include <sys/socket.h> #define BTPROTO_L2CAP 0 #define BTPROTO_SCO 2 #define BTPROTO_RFCOMM 3 int main() { int fd; struct linger ling; fd = socket(PF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM); //or: fd = socket(PF_BLUETOOTH, SOCK_DGRAM, BTPROTO_L2CAP); //or: fd = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_SCO); ling.l_onoff = 1; ling.l_linger = 1000000000; setsockopt(fd, SOL_SOCKET, SO_LINGER, &ling, sizeof(ling)); return 0; } Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 093facf3634da1b0c2cc7ed106f1983da901bbab upstream.

If the current process is exiting, lingering on socket close will make
it unkillable, so we should avoid it.

Reproducer:

  #include <sys/types.h>
  #include <sys/socket.h>

  #define BTPROTO_L2CAP   0
  #define BTPROTO_SCO     2
  #define BTPROTO_RFCOMM  3

  int main()
  {
          int fd;
          struct linger ling;

          fd = socket(PF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
          //or: fd = socket(PF_BLUETOOTH, SOCK_DGRAM, BTPROTO_L2CAP);
          //or: fd = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_SCO);

          ling.l_onoff = 1;
          ling.l_linger = 1000000000;
          setsockopt(fd, SOL_SOCKET, SO_LINGER, &ling, sizeof(ling));

          return 0;
  }

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: Fix locking of hdev when calling into SMP code 2014-07-09T18:14:01+00:00 Johan Hedberg johan.hedberg@intel.com 2014-06-13T07:22:28+00:00 f2f90dd36487290ff0bf60e341839a606045aef8 commit c73f94b8c093a615ce80eabbde0ac6eb9abfe31a upstream. The SMP code expects hdev to be unlocked since e.g. crypto functions will try to (re)lock it. Therefore, we need to release the lock before calling into smp.c from mgmt.c. Without this we risk a deadlock whenever the smp_user_confirm_reply() function is called. Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Tested-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c73f94b8c093a615ce80eabbde0ac6eb9abfe31a upstream.

The SMP code expects hdev to be unlocked since e.g. crypto functions
will try to (re)lock it. Therefore, we need to release the lock before
calling into smp.c from mgmt.c. Without this we risk a deadlock whenever
the smp_user_confirm_reply() function is called.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Tested-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: Fix check for connection encryption 2014-07-09T18:14:01+00:00 Johan Hedberg johan.hedberg@intel.com 2014-06-10T06:54:24+00:00 07f5ed51cb551e89d89766ba87e7313aae53e139 commit e694788d73efe139b24f78b036deb97fe57fa8cb upstream. The conn->link_key variable tracks the type of link key in use. It is set whenever we respond to a link key request as well as when we get a link key notification event. These two events do not however always guarantee that encryption is enabled: getting a link key request and responding to it may only mean that the remote side has requested authentication but not encryption. On the other hand, the encrypt change event is a certain guarantee that encryption is enabled. The real encryption state is already tracked in the conn->link_mode variable through the HCI_LM_ENCRYPT bit. This patch fixes a check for encryption in the hci_conn_auth function to use the proper conn->link_mode value and thereby eliminates the chance of a false positive result. Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e694788d73efe139b24f78b036deb97fe57fa8cb upstream.

The conn->link_key variable tracks the type of link key in use. It is
set whenever we respond to a link key request as well as when we get a
link key notification event.

These two events do not however always guarantee that encryption is
enabled: getting a link key request and responding to it may only mean
that the remote side has requested authentication but not encryption. On
the other hand, the encrypt change event is a certain guarantee that
encryption is enabled. The real encryption state is already tracked in
the conn->link_mode variable through the HCI_LM_ENCRYPT bit.

This patch fixes a check for encryption in the hci_conn_auth function to
use the proper conn->link_mode value and thereby eliminates the chance
of a false positive result.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: Fix SSP acceptor just-works confirmation without MITM 2014-07-09T18:14:00+00:00 Johan Hedberg johan.hedberg@intel.com 2014-06-09T10:58:14+00:00 6ab84785311dc4d0348e6bd4e1c491293b770b98 commit ba15a58b179ed76a7e887177f2b06de12c58ec8f upstream. From the Bluetooth Core Specification 4.1 page 1958: "if both devices have set the Authentication_Requirements parameter to one of the MITM Protection Not Required options, authentication stage 1 shall function as if both devices set their IO capabilities to DisplayOnly (e.g., Numeric comparison with automatic confirmation on both devices)" So far our implementation has done user confirmation for all just-works cases regardless of the MITM requirements, however following the specification to the word means that we should not be doing confirmation when neither side has the MITM flag set. Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Tested-by: Szymon Janc <szymon.janc@tieto.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ba15a58b179ed76a7e887177f2b06de12c58ec8f upstream.

From the Bluetooth Core Specification 4.1 page 1958:

"if both devices have set the Authentication_Requirements parameter to
one of the MITM Protection Not Required options, authentication stage 1
shall function as if both devices set their IO capabilities to
DisplayOnly (e.g., Numeric comparison with automatic confirmation on
both devices)"

So far our implementation has done user confirmation for all just-works
cases regardless of the MITM requirements, however following the
specification to the word means that we should not be doing confirmation
when neither side has the MITM flag set.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Tested-by: Szymon Janc <szymon.janc@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: Fix L2CAP deadlock 2014-07-01T03:09:44+00:00 Jukka Taimisto jtt@codenomicon.com 2014-05-22T10:02:39+00:00 8d26d1a24bd8523902d8987a9b69462380c70fc3 commit 8a96f3cd22878fc0bb564a8478a6e17c0b8dca73 upstream. -[0x01 Introduction We have found a programming error causing a deadlock in Bluetooth subsystem of Linux kernel. The problem is caused by missing release_sock() call when L2CAP connection creation fails due full accept queue. The issue can be reproduced with 3.15-rc5 kernel and is also present in earlier kernels. -[0x02 Details The problem occurs when multiple L2CAP connections are created to a PSM which contains listening socket (like SDP) and left pending, for example, configuration (the underlying ACL link is not disconnected between connections). When L2CAP connection request is received and listening socket is found the l2cap_sock_new_connection_cb() function (net/bluetooth/l2cap_sock.c) is called. This function locks the 'parent' socket and then checks if the accept queue is full. 1178 lock_sock(parent); 1179 1180 /* Check for backlog size */ 1181 if (sk_acceptq_is_full(parent)) { 1182 BT_DBG("backlog full %d", parent->sk_ack_backlog); 1183 return NULL; 1184 } If case the accept queue is full NULL is returned, but the 'parent' socket is not released. Thus when next L2CAP connection request is received the code blocks on lock_sock() since the parent is still locked. Also note that for connections already established and waiting for configuration to complete a timeout will occur and l2cap_chan_timeout() (net/bluetooth/l2cap_core.c) will be called. All threads calling this function will also be blocked waiting for the channel mutex since the thread which is waiting on lock_sock() alread holds the channel mutex. We were able to reproduce this by sending continuously L2CAP connection request followed by disconnection request containing invalid CID. This left the created connections pending configuration. After the deadlock occurs it is impossible to kill bluetoothd, btmon will not get any more data etc. requiring reboot to recover. -[0x03 Fix Releasing the 'parent' socket when l2cap_sock_new_connection_cb() returns NULL seems to fix the issue. Signed-off-by: Jukka Taimisto <jtt@codenomicon.com> Reported-by: Tommi Mäkilä <tmakila@codenomicon.com> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8a96f3cd22878fc0bb564a8478a6e17c0b8dca73 upstream.

-[0x01 Introduction

We have found a programming error causing a deadlock in Bluetooth subsystem
of Linux kernel. The problem is caused by missing release_sock() call when
L2CAP connection creation fails due full accept queue.

The issue can be reproduced with 3.15-rc5 kernel and is also present in
earlier kernels.

-[0x02 Details

The problem occurs when multiple L2CAP connections are created to a PSM which
contains listening socket (like SDP) and left pending, for example,
configuration (the underlying ACL link is not disconnected between
connections).

When L2CAP connection request is received and listening socket is found the
l2cap_sock_new_connection_cb() function (net/bluetooth/l2cap_sock.c) is called.
This function locks the 'parent' socket and then checks if the accept queue
is full.

1178         lock_sock(parent);
1179
1180         /* Check for backlog size */
1181         if (sk_acceptq_is_full(parent)) {
1182                 BT_DBG("backlog full %d", parent->sk_ack_backlog);
1183                 return NULL;
1184         }

If case the accept queue is full NULL is returned, but the 'parent' socket
is not released. Thus when next L2CAP connection request is received the code
blocks on lock_sock() since the parent is still locked.

Also note that for connections already established and waiting for
configuration to complete a timeout will occur and l2cap_chan_timeout()
(net/bluetooth/l2cap_core.c) will be called. All threads calling this
function will also be blocked waiting for the channel mutex since the thread
which is waiting on lock_sock() alread holds the channel mutex.

We were able to reproduce this by sending continuously L2CAP connection
request followed by disconnection request containing invalid CID. This left
the created connections pending configuration.

After the deadlock occurs it is impossible to kill bluetoothd, btmon will not
get any more data etc. requiring reboot to recover.

-[0x03 Fix

Releasing the 'parent' socket when l2cap_sock_new_connection_cb() returns NULL
seems to fix the issue.

Signed-off-by: Jukka Taimisto <jtt@codenomicon.com>
Reported-by: Tommi Mäkilä <tmakila@codenomicon.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: Fix redundant encryption request for reauthentication 2014-06-07T20:25:33+00:00 Johan Hedberg johan.hedberg@intel.com 2014-04-11T19:02:32+00:00 6142655f2298ea3eca194d36a09cfba9a402fc25 commit 09da1f3463eb81d59685df723b1c5950b7570340 upstream. When we're performing reauthentication (in order to elevate the security level from an unauthenticated key to an authenticated one) we do not need to issue any encryption command once authentication completes. Since the trigger for the encryption HCI command is the ENCRYPT_PEND flag this flag should not be set in this scenario. Instead, the REAUTH_PEND flag takes care of all necessary steps for reauthentication. Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 09da1f3463eb81d59685df723b1c5950b7570340 upstream.

When we're performing reauthentication (in order to elevate the
security level from an unauthenticated key to an authenticated one) we
do not need to issue any encryption command once authentication
completes. Since the trigger for the encryption HCI command is the
ENCRYPT_PEND flag this flag should not be set in this scenario.
Instead, the REAUTH_PEND flag takes care of all necessary steps for
reauthentication.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: Fix triggering BR/EDR L2CAP Connect too early 2014-06-07T20:25:33+00:00 Johan Hedberg johan.hedberg@intel.com 2014-04-11T19:02:31+00:00 2ef1b8b7d71559d3fc6ef6731a9244850a76f58d commit 9eb1fbfa0a737fd4d3a6d12d71c5ea9af622b887 upstream. Commit 1c2e004183178 introduced an event handler for the encryption key refresh complete event with the intent of fixing some LE/SMP cases. However, this event is shared with BR/EDR and there we actually want to act only on the auth_complete event (which comes after the key refresh). If we do not do this we may trigger an L2CAP Connect Request too early and cause the remote side to return a security block error. Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9eb1fbfa0a737fd4d3a6d12d71c5ea9af622b887 upstream.

Commit 1c2e004183178 introduced an event handler for the encryption key
refresh complete event with the intent of fixing some LE/SMP cases.
However, this event is shared with BR/EDR and there we actually want to
act only on the auth_complete event (which comes after the key refresh).

If we do not do this we may trigger an L2CAP Connect Request too early
and cause the remote side to return a security block error.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: Fix removing Long Term Key 2014-04-27T00:15:34+00:00 Claudio Takahasi claudio.takahasi@openbossa.org 2013-07-25T19:34:24+00:00 2dbecc73f3b8aa4a6d4c0465eb276ba08161e79d commit 5981a8821b774ada0be512fd9bad7c241e17657e upstream. This patch fixes authentication failure on LE link re-connection when BlueZ acts as slave (peripheral). LTK is removed from the internal list after its first use causing PIN or Key missing reply when re-connecting the link. The LE Long Term Key Request event indicates that the master is attempting to encrypt or re-encrypt the link. Pre-condition: BlueZ host paired and running as slave. How to reproduce(master): 1) Establish an ACL LE encrypted link 2) Disconnect the link 3) Try to re-establish the ACL LE encrypted link (fails) > HCI Event: LE Meta Event (0x3e) plen 19 LE Connection Complete (0x01) Status: Success (0x00) Handle: 64 Role: Slave (0x01) ... @ Device Connected: 00:02:72:DC:29:C9 (1) flags 0x0000 > HCI Event: LE Meta Event (0x3e) plen 13 LE Long Term Key Request (0x05) Handle: 64 Random number: 875be18439d9aa37 Encryption diversifier: 0x76ed < HCI Command: LE Long Term Key Request Reply (0x08|0x001a) plen 18 Handle: 64 Long term key: 2aa531db2fce9f00a0569c7d23d17409 > HCI Event: Command Complete (0x0e) plen 6 LE Long Term Key Request Reply (0x08|0x001a) ncmd 1 Status: Success (0x00) Handle: 64 > HCI Event: Encryption Change (0x08) plen 4 Status: Success (0x00) Handle: 64 Encryption: Enabled with AES-CCM (0x01) ... @ Device Disconnected: 00:02:72:DC:29:C9 (1) reason 3 < HCI Command: LE Set Advertise Enable (0x08|0x000a) plen 1 Advertising: Enabled (0x01) > HCI Event: Command Complete (0x0e) plen 4 LE Set Advertise Enable (0x08|0x000a) ncmd 1 Status: Success (0x00) > HCI Event: LE Meta Event (0x3e) plen 19 LE Connection Complete (0x01) Status: Success (0x00) Handle: 64 Role: Slave (0x01) ... @ Device Connected: 00:02:72:DC:29:C9 (1) flags 0x0000 > HCI Event: LE Meta Event (0x3e) plen 13 LE Long Term Key Request (0x05) Handle: 64 Random number: 875be18439d9aa37 Encryption diversifier: 0x76ed < HCI Command: LE Long Term Key Request Neg Reply (0x08|0x001b) plen 2 Handle: 64 > HCI Event: Command Complete (0x0e) plen 6 LE Long Term Key Request Neg Reply (0x08|0x001b) ncmd 1 Status: Success (0x00) Handle: 64 > HCI Event: Disconnect Complete (0x05) plen 4 Status: Success (0x00) Handle: 64 Reason: Authentication Failure (0x05) @ Device Disconnected: 00:02:72:DC:29:C9 (1) reason 0 Signed-off-by: Claudio Takahasi <claudio.takahasi@openbossa.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5981a8821b774ada0be512fd9bad7c241e17657e upstream.

This patch fixes authentication failure on LE link re-connection when
BlueZ acts as slave (peripheral). LTK is removed from the internal list
after its first use causing PIN or Key missing reply when re-connecting
the link. The LE Long Term Key Request event indicates that the master
is attempting to encrypt or re-encrypt the link.

Pre-condition: BlueZ host paired and running as slave.
How to reproduce(master):

  1) Establish an ACL LE encrypted link
  2) Disconnect the link
  3) Try to re-establish the ACL LE encrypted link (fails)

> HCI Event: LE Meta Event (0x3e) plen 19
      LE Connection Complete (0x01)
        Status: Success (0x00)
        Handle: 64
        Role: Slave (0x01)
...
@ Device Connected: 00:02:72:DC:29:C9 (1) flags 0x0000
> HCI Event: LE Meta Event (0x3e) plen 13
      LE Long Term Key Request (0x05)
        Handle: 64
        Random number: 875be18439d9aa37
        Encryption diversifier: 0x76ed
< HCI Command: LE Long Term Key Request Reply (0x08|0x001a) plen 18
        Handle: 64
        Long term key: 2aa531db2fce9f00a0569c7d23d17409
> HCI Event: Command Complete (0x0e) plen 6
      LE Long Term Key Request Reply (0x08|0x001a) ncmd 1
        Status: Success (0x00)
        Handle: 64
> HCI Event: Encryption Change (0x08) plen 4
        Status: Success (0x00)
        Handle: 64
        Encryption: Enabled with AES-CCM (0x01)
...
@ Device Disconnected: 00:02:72:DC:29:C9 (1) reason 3
< HCI Command: LE Set Advertise Enable (0x08|0x000a) plen 1
        Advertising: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Advertise Enable (0x08|0x000a) ncmd 1
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 19
      LE Connection Complete (0x01)
        Status: Success (0x00)
        Handle: 64
        Role: Slave (0x01)
...
@ Device Connected: 00:02:72:DC:29:C9 (1) flags 0x0000
> HCI Event: LE Meta Event (0x3e) plen 13
      LE Long Term Key Request (0x05)
        Handle: 64
        Random number: 875be18439d9aa37
        Encryption diversifier: 0x76ed
< HCI Command: LE Long Term Key Request Neg Reply (0x08|0x001b) plen 2
        Handle: 64
> HCI Event: Command Complete (0x0e) plen 6
      LE Long Term Key Request Neg Reply (0x08|0x001b) ncmd 1
        Status: Success (0x00)
        Handle: 64
> HCI Event: Disconnect Complete (0x05) plen 4
        Status: Success (0x00)
        Handle: 64
        Reason: Authentication Failure (0x05)
@ Device Disconnected: 00:02:72:DC:29:C9 (1) reason 0

Signed-off-by: Claudio Takahasi <claudio.takahasi@openbossa.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: rework recvmsg handler msg_name and msg_namelen logic 2013-12-08T15:29:25+00:00 Hannes Frederic Sowa hannes@stressinduktion.org 2013-11-21T02:14:22+00:00 2f73d7fde99d702cba6a05062c27605a6eef1b78 [ Upstream commit f3d3342602f8bcbf37d7c46641cb9bca7618eb1c ] This patch now always passes msg->msg_namelen as 0. recvmsg handlers must set msg_namelen to the proper size <= sizeof(struct sockaddr_storage) to return msg_name to the user. This prevents numerous uninitialized memory leaks we had in the recvmsg handlers and makes it harder for new code to accidentally leak uninitialized memory. Optimize for the case recvfrom is called with NULL as address. We don't need to copy the address at all, so set it to NULL before invoking the recvmsg handler. We can do so, because all the recvmsg handlers must cope with the case a plain read() is called on them. read() also sets msg_name to NULL. Also document these changes in include/linux/net.h as suggested by David Miller. Changes since RFC: Set msg->msg_name = NULL if user specified a NULL in msg_name but had a non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't affect sendto as it would bail out earlier while trying to copy-in the address. It also more naturally reflects the logic by the callers of verify_iovec. With this change in place I could remove " if (!uaddr || msg_sys->msg_namelen == 0) msg->msg_name = NULL ". This change does not alter the user visible error logic as we ignore msg_namelen as long as msg_name is NULL. Also remove two unnecessary curly brackets in ___sys_recvmsg and change comments to netdev style. Cc: David Miller <davem@davemloft.net> Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit f3d3342602f8bcbf37d7c46641cb9bca7618eb1c ]

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
	msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>