1. 23 8月, 2012 3 次提交
  2. 22 8月, 2012 4 次提交
    • E
      af_netlink: force credentials passing [CVE-2012-3520] · e0e3cea4
      Eric Dumazet 提交于
      Pablo Neira Ayuso discovered that avahi and
      potentially NetworkManager accept spoofed Netlink messages because of a
      kernel bug.  The kernel passes all-zero SCM_CREDENTIALS ancillary data
      to the receiver if the sender did not provide such data, instead of not
      including any such data at all or including the correct data from the
      peer (as it is the case with AF_UNIX).
      
      This bug was introduced in commit 16e57262
      (af_unix: dont send SCM_CREDENTIALS by default)
      
      This patch forces passing credentials for netlink, as
      before the regression.
      
      Another fix would be to not add SCM_CREDENTIALS in
      netlink messages if not provided by the sender, but it
      might break some programs.
      
      With help from Florian Weimer & Petr Matousek
      
      This issue is designated as CVE-2012-3520
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Petr Matousek <pmatouse@redhat.com>
      Cc: Florian Weimer <fweimer@redhat.com>
      Cc: Pablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e0e3cea4
    • E
      ipv4: fix ip header ident selection in __ip_make_skb() · a9915a1b
      Eric Dumazet 提交于
      Christian Casteyde reported a kmemcheck 32-bit read from uninitialized
      memory in __ip_select_ident().
      
      It turns out that __ip_make_skb() called ip_select_ident() before
      properly initializing iph->daddr.
      
      This is a bug uncovered by commit 1d861aa4 (inet: Minimize use of
      cached route inetpeer.)
      
      Addresses https://bugzilla.kernel.org/show_bug.cgi?id=46131Reported-by: NChristian Casteyde <casteyde.christian@free.fr>
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Stephen Hemminger <shemminger@vyatta.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a9915a1b
    • C
      ipv4: Use newinet->inet_opt in inet_csk_route_child_sock() · 1a7b27c9
      Christoph Paasch 提交于
      Since 0e734419 ("ipv4: Use inet_csk_route_child_sock() in DCCP and
      TCP."), inet_csk_route_child_sock() is called instead of
      inet_csk_route_req().
      
      However, after creating the child-sock in tcp/dccp_v4_syn_recv_sock(),
      ireq->opt is set to NULL, before calling inet_csk_route_child_sock().
      Thus, inside inet_csk_route_child_sock() opt is always NULL and the
      SRR-options are not respected anymore.
      Packets sent by the server won't have the correct destination-IP.
      
      This patch fixes it by accessing newinet->inet_opt instead of ireq->opt
      inside inet_csk_route_child_sock().
      Reported-by: NLuca Boccassi <luca.boccassi@gmail.com>
      Signed-off-by: NChristoph Paasch <christoph.paasch@uclouvain.be>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1a7b27c9
    • E
      tcp: fix possible socket refcount problem · 144d56e9
      Eric Dumazet 提交于
      Commit 6f458dfb (tcp: improve latencies of timer triggered events)
      added bug leading to following trace :
      
      [ 2866.131281] IPv4: Attempt to release TCP socket in state 1 ffff880019ec0000
      [ 2866.131726]
      [ 2866.132188] =========================
      [ 2866.132281] [ BUG: held lock freed! ]
      [ 2866.132281] 3.6.0-rc1+ #622 Not tainted
      [ 2866.132281] -------------------------
      [ 2866.132281] kworker/0:1/652 is freeing memory ffff880019ec0000-ffff880019ec0a1f, with a lock still held there!
      [ 2866.132281]  (sk_lock-AF_INET-RPC){+.+...}, at: [<ffffffff81903619>] tcp_sendmsg+0x29/0xcc6
      [ 2866.132281] 4 locks held by kworker/0:1/652:
      [ 2866.132281]  #0:  (rpciod){.+.+.+}, at: [<ffffffff81083567>] process_one_work+0x1de/0x47f
      [ 2866.132281]  #1:  ((&task->u.tk_work)){+.+.+.}, at: [<ffffffff81083567>] process_one_work+0x1de/0x47f
      [ 2866.132281]  #2:  (sk_lock-AF_INET-RPC){+.+...}, at: [<ffffffff81903619>] tcp_sendmsg+0x29/0xcc6
      [ 2866.132281]  #3:  (&icsk->icsk_retransmit_timer){+.-...}, at: [<ffffffff81078017>] run_timer_softirq+0x1ad/0x35f
      [ 2866.132281]
      [ 2866.132281] stack backtrace:
      [ 2866.132281] Pid: 652, comm: kworker/0:1 Not tainted 3.6.0-rc1+ #622
      [ 2866.132281] Call Trace:
      [ 2866.132281]  <IRQ>  [<ffffffff810bc527>] debug_check_no_locks_freed+0x112/0x159
      [ 2866.132281]  [<ffffffff818a0839>] ? __sk_free+0xfd/0x114
      [ 2866.132281]  [<ffffffff811549fa>] kmem_cache_free+0x6b/0x13a
      [ 2866.132281]  [<ffffffff818a0839>] __sk_free+0xfd/0x114
      [ 2866.132281]  [<ffffffff818a08c0>] sk_free+0x1c/0x1e
      [ 2866.132281]  [<ffffffff81911e1c>] tcp_write_timer+0x51/0x56
      [ 2866.132281]  [<ffffffff81078082>] run_timer_softirq+0x218/0x35f
      [ 2866.132281]  [<ffffffff81078017>] ? run_timer_softirq+0x1ad/0x35f
      [ 2866.132281]  [<ffffffff810f5831>] ? rb_commit+0x58/0x85
      [ 2866.132281]  [<ffffffff81911dcb>] ? tcp_write_timer_handler+0x148/0x148
      [ 2866.132281]  [<ffffffff81070bd6>] __do_softirq+0xcb/0x1f9
      [ 2866.132281]  [<ffffffff81a0a00c>] ? _raw_spin_unlock+0x29/0x2e
      [ 2866.132281]  [<ffffffff81a1227c>] call_softirq+0x1c/0x30
      [ 2866.132281]  [<ffffffff81039f38>] do_softirq+0x4a/0xa6
      [ 2866.132281]  [<ffffffff81070f2b>] irq_exit+0x51/0xad
      [ 2866.132281]  [<ffffffff81a129cd>] do_IRQ+0x9d/0xb4
      [ 2866.132281]  [<ffffffff81a0a3ef>] common_interrupt+0x6f/0x6f
      [ 2866.132281]  <EOI>  [<ffffffff8109d006>] ? sched_clock_cpu+0x58/0xd1
      [ 2866.132281]  [<ffffffff81a0a172>] ? _raw_spin_unlock_irqrestore+0x4c/0x56
      [ 2866.132281]  [<ffffffff81078692>] mod_timer+0x178/0x1a9
      [ 2866.132281]  [<ffffffff818a00aa>] sk_reset_timer+0x19/0x26
      [ 2866.132281]  [<ffffffff8190b2cc>] tcp_rearm_rto+0x99/0xa4
      [ 2866.132281]  [<ffffffff8190dfba>] tcp_event_new_data_sent+0x6e/0x70
      [ 2866.132281]  [<ffffffff8190f7ea>] tcp_write_xmit+0x7de/0x8e4
      [ 2866.132281]  [<ffffffff818a565d>] ? __alloc_skb+0xa0/0x1a1
      [ 2866.132281]  [<ffffffff8190f952>] __tcp_push_pending_frames+0x2e/0x8a
      [ 2866.132281]  [<ffffffff81904122>] tcp_sendmsg+0xb32/0xcc6
      [ 2866.132281]  [<ffffffff819229c2>] inet_sendmsg+0xaa/0xd5
      [ 2866.132281]  [<ffffffff81922918>] ? inet_autobind+0x5f/0x5f
      [ 2866.132281]  [<ffffffff810ee7f1>] ? trace_clock_local+0x9/0xb
      [ 2866.132281]  [<ffffffff8189adab>] sock_sendmsg+0xa3/0xc4
      [ 2866.132281]  [<ffffffff810f5de6>] ? rb_reserve_next_event+0x26f/0x2d5
      [ 2866.132281]  [<ffffffff8103e6a9>] ? native_sched_clock+0x29/0x6f
      [ 2866.132281]  [<ffffffff8103e6f8>] ? sched_clock+0x9/0xd
      [ 2866.132281]  [<ffffffff810ee7f1>] ? trace_clock_local+0x9/0xb
      [ 2866.132281]  [<ffffffff8189ae03>] kernel_sendmsg+0x37/0x43
      [ 2866.132281]  [<ffffffff8199ce49>] xs_send_kvec+0x77/0x80
      [ 2866.132281]  [<ffffffff8199cec1>] xs_sendpages+0x6f/0x1a0
      [ 2866.132281]  [<ffffffff8107826d>] ? try_to_del_timer_sync+0x55/0x61
      [ 2866.132281]  [<ffffffff8199d0d2>] xs_tcp_send_request+0x55/0xf1
      [ 2866.132281]  [<ffffffff8199bb90>] xprt_transmit+0x89/0x1db
      [ 2866.132281]  [<ffffffff81999bcd>] ? call_connect+0x3c/0x3c
      [ 2866.132281]  [<ffffffff81999d92>] call_transmit+0x1c5/0x20e
      [ 2866.132281]  [<ffffffff819a0d55>] __rpc_execute+0x6f/0x225
      [ 2866.132281]  [<ffffffff81999bcd>] ? call_connect+0x3c/0x3c
      [ 2866.132281]  [<ffffffff819a0f33>] rpc_async_schedule+0x28/0x34
      [ 2866.132281]  [<ffffffff810835d6>] process_one_work+0x24d/0x47f
      [ 2866.132281]  [<ffffffff81083567>] ? process_one_work+0x1de/0x47f
      [ 2866.132281]  [<ffffffff819a0f0b>] ? __rpc_execute+0x225/0x225
      [ 2866.132281]  [<ffffffff81083a6d>] worker_thread+0x236/0x317
      [ 2866.132281]  [<ffffffff81083837>] ? process_scheduled_works+0x2f/0x2f
      [ 2866.132281]  [<ffffffff8108b7b8>] kthread+0x9a/0xa2
      [ 2866.132281]  [<ffffffff81a12184>] kernel_thread_helper+0x4/0x10
      [ 2866.132281]  [<ffffffff81a0a4b0>] ? retint_restore_args+0x13/0x13
      [ 2866.132281]  [<ffffffff8108b71e>] ? __init_kthread_worker+0x5a/0x5a
      [ 2866.132281]  [<ffffffff81a12180>] ? gs_change+0x13/0x13
      [ 2866.308506] IPv4: Attempt to release TCP socket in state 1 ffff880019ec0000
      [ 2866.309689] =============================================================================
      [ 2866.310254] BUG TCP (Not tainted): Object already free
      [ 2866.310254] -----------------------------------------------------------------------------
      [ 2866.310254]
      
      The bug comes from the fact that timer set in sk_reset_timer() can run
      before we actually do the sock_hold(). socket refcount reaches zero and
      we free the socket too soon.
      
      timer handler is not allowed to reduce socket refcnt if socket is owned
      by the user, or we need to change sk_reset_timer() implementation.
      
      We should take a reference on the socket in case TCP_DELACK_TIMER_DEFERRED
      or TCP_DELACK_TIMER_DEFERRED bit are set in tsq_flags
      
      Also fix a typo in tcp_delack_timer(), where TCP_WRITE_TIMER_DEFERRED
      was used instead of TCP_DELACK_TIMER_DEFERRED.
      
      For consistency, use same socket refcount change for TCP_MTU_REDUCED_DEFERRED,
      even if not fired from a timer.
      Reported-by: NFengguang Wu <fengguang.wu@intel.com>
      Tested-by: NFengguang Wu <fengguang.wu@intel.com>
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      144d56e9
  3. 20 8月, 2012 19 次提交
  4. 17 8月, 2012 7 次提交
  5. 16 8月, 2012 7 次提交
    • P
      netfilter: nf_ct_expect: fix possible access to uninitialized timer · 2614f864
      Pablo Neira Ayuso 提交于
      In __nf_ct_expect_check, the function refresh_timer returns 1
      if a matching expectation is found and its timer is successfully
      refreshed. This results in nf_ct_expect_related returning 0.
      Note that at this point:
      
      - the passed expectation is not inserted in the expectation table
        and its timer was not initialized, since we have refreshed one
        matching/existing expectation.
      
      - nf_ct_expect_alloc uses kmem_cache_alloc, so the expectation
        timer is in some undefined state just after the allocation,
        until it is appropriately initialized.
      
      This can be a problem for the SIP helper during the expectation
      addition:
      
       ...
       if (nf_ct_expect_related(rtp_exp) == 0) {
               if (nf_ct_expect_related(rtcp_exp) != 0)
                       nf_ct_unexpect_related(rtp_exp);
       ...
      
      Note that nf_ct_expect_related(rtp_exp) may return 0 for the timer refresh
      case that is detailed above. Then, if nf_ct_unexpect_related(rtcp_exp)
      returns != 0, nf_ct_unexpect_related(rtp_exp) is called, which does:
      
       spin_lock_bh(&nf_conntrack_lock);
       if (del_timer(&exp->timeout)) {
               nf_ct_unlink_expect(exp);
               nf_ct_expect_put(exp);
       }
       spin_unlock_bh(&nf_conntrack_lock);
      
      Note that del_timer always returns false if the timer has been
      initialized.  However, the timer was not initialized since setup_timer
      was not called, therefore, the expectation timer remains in some
      undefined state. If I'm not missing anything, this may lead to the
      removal an unexistent expectation.
      
      To fix this, the optimization that allows refreshing an expectation
      is removed. Now nf_conntrack_expect_related looks more consistent
      to me since it always add the expectation in case that it returns
      success.
      
      Thanks to Patrick McHardy for participating in the discussion of
      this patch.
      
      I think this may be the source of the problem described by:
      http://marc.info/?l=netfilter-devel&m=134073514719421&w=2Reported-by: NRafal Fitt <rafalf@aplusc.com.pl>
      Acked-by: NPatrick McHardy <kaber@trash.net>
      Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
      2614f864
    • M
      net: fix info leak in compat dev_ifconf() · 43da5f2e
      Mathias Krause 提交于
      The implementation of dev_ifconf() for the compat ioctl interface uses
      an intermediate ifc structure allocated in userland for the duration of
      the syscall. Though, it fails to initialize the padding bytes inserted
      for alignment and that for leaks four bytes of kernel stack. Add an
      explicit memset(0) before filling the structure to avoid the info leak.
      Signed-off-by: NMathias Krause <minipli@googlemail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      43da5f2e
    • M
      ipvs: fix info leak in getsockopt(IP_VS_SO_GET_TIMEOUT) · 2d8a041b
      Mathias Krause 提交于
      If at least one of CONFIG_IP_VS_PROTO_TCP or CONFIG_IP_VS_PROTO_UDP is
      not set, __ip_vs_get_timeouts() does not fully initialize the structure
      that gets copied to userland and that for leaks up to 12 bytes of kernel
      stack. Add an explicit memset(0) before passing the structure to
      __ip_vs_get_timeouts() to avoid the info leak.
      Signed-off-by: NMathias Krause <minipli@googlemail.com>
      Cc: Wensong Zhang <wensong@linux-vs.org>
      Cc: Simon Horman <horms@verge.net.au>
      Cc: Julian Anastasov <ja@ssi.bg>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2d8a041b
    • M
      dccp: fix info leak via getsockopt(DCCP_SOCKOPT_CCID_TX_INFO) · 7b07f8eb
      Mathias Krause 提交于
      The CCID3 code fails to initialize the trailing padding bytes of struct
      tfrc_tx_info added for alignment on 64 bit architectures. It that for
      potentially leaks four bytes kernel stack via the getsockopt() syscall.
      Add an explicit memset(0) before filling the structure to avoid the
      info leak.
      Signed-off-by: NMathias Krause <minipli@googlemail.com>
      Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      7b07f8eb
    • M
      dccp: check ccid before dereferencing · 276bdb82
      Mathias Krause 提交于
      ccid_hc_rx_getsockopt() and ccid_hc_tx_getsockopt() might be called with
      a NULL ccid pointer leading to a NULL pointer dereference. This could
      lead to a privilege escalation if the attacker is able to map page 0 and
      prepare it with a fake ccid_ops pointer.
      Signed-off-by: NMathias Krause <minipli@googlemail.com>
      Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk>
      Cc: stable@vger.kernel.org
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      276bdb82
    • M
      llc: fix info leak via getsockname() · 3592aaeb
      Mathias Krause 提交于
      The LLC code wrongly returns 0, i.e. "success", when the socket is
      zapped. Together with the uninitialized uaddrlen pointer argument from
      sys_getsockname this leads to an arbitrary memory leak of up to 128
      bytes kernel stack via the getsockname() syscall.
      
      Return an error instead when the socket is zapped to prevent the info
      leak. Also remove the unnecessary memset(0). We don't directly write to
      the memory pointed by uaddr but memcpy() a local structure at the end of
      the function that is properly initialized.
      Signed-off-by: NMathias Krause <minipli@googlemail.com>
      Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3592aaeb
    • M
      l2tp: fix info leak via getsockname() · 04d4fbca
      Mathias Krause 提交于
      The L2TP code for IPv6 fails to initialize the l2tp_unused member of
      struct sockaddr_l2tpip6 and that for leaks two bytes kernel stack via
      the getsockname() syscall. Initialize l2tp_unused with 0 to avoid the
      info leak.
      Signed-off-by: NMathias Krause <minipli@googlemail.com>
      Cc: James Chapman <jchapman@katalix.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      04d4fbca