1. 07 Jun, 2020 33 commits
  2. 03 Jun, 2020 7 commits
    • Greg Kroah-Hartman's avatar
      Linux 5.4.44 · 55852b3f
      Greg Kroah-Hartman authored
      55852b3f
    • Changbin Du's avatar
      perf: Make perf able to build with latest libbfd · f2a9b00a
      Changbin Du authored
      commit 0ada120c upstream.
      
      libbfd has changed the bfd_section_* macros to inline functions
      bfd_section_<field> since 2019-09-18. See below two commits:
        o http://www.sourceware.org/ml/gdb-cvs/2019-09/msg00064.html
        o https://www.sourceware.org/ml/gdb-cvs/2019-09/msg00072.html
      
      
      
      This fix make perf able to build with both old and new libbfd.
      Signed-off-by: default avatarChangbin Du <changbin.du@gmail.com>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Link: http://lore.kernel.org/lkml/20200128152938.31413-1-changbin.du@gmail.com
      
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Marek Vasut <marex@denx.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      f2a9b00a
    • Pablo Neira Ayuso's avatar
      netfilter: nf_conntrack_pptp: fix compilation warning with W=1 build · 3f57fa84
      Pablo Neira Ayuso authored
      commit 4946ea5c
      
       upstream.
      
      >> include/linux/netfilter/nf_conntrack_pptp.h:13:20: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers]
      extern const char *const pptp_msg_name(u_int16_t msg);
      ^~~~~~
      Reported-by: default avatarkbuild test robot <lkp@intel.com>
      Fixes: 4c559f15
      
       ("netfilter: nf_conntrack_pptp: prevent buffer overflows in debug code")
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      3f57fa84
    • Nathan Chancellor's avatar
      netfilter: conntrack: Pass value of ctinfo to __nf_conntrack_update · 7a075390
      Nathan Chancellor authored
      commit 46c1e062 upstream.
      
      Clang warns:
      
      net/netfilter/nf_conntrack_core.c:2068:21: warning: variable 'ctinfo' is
      uninitialized when used here [-Wuninitialized]
              nf_ct_set(skb, ct, ctinfo);
                                 ^~~~~~
      net/netfilter/nf_conntrack_core.c:2024:2: note: variable 'ctinfo' is
      declared here
              enum ip_conntrack_info ctinfo;
              ^
      1 warning generated.
      
      nf_conntrack_update was split up into nf_conntrack_update and
      __nf_conntrack_update, where the assignment of ctinfo is in
      nf_conntrack_update but it is used in __nf_conntrack_update.
      
      Pass the value of ctinfo from nf_conntrack_update to
      __nf_conntrack_update so that uninitialized memory is not used
      and everything works properly.
      
      Fixes: ee04805f ("netfilter: conntrack: make conntrack userspace helpers work again")
      Link: https://github.com/ClangBuiltLinux/linux/issues/1039
      
      Signed-off-by: default avatarNathan Chancellor <natechancellor@gmail.com>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7a075390
    • Pablo Neira Ayuso's avatar
      netfilter: conntrack: comparison of unsigned in cthelper confirmation · 987de40b
      Pablo Neira Ayuso authored
      commit 94945ad2
      
       upstream.
      
      net/netfilter/nf_conntrack_core.c: In function nf_confirm_cthelper:
      net/netfilter/nf_conntrack_core.c:2117:15: warning: comparison of unsigned expression in < 0 is always false [-Wtype-limits]
       2117 |   if (protoff < 0 || (frag_off & htons(~0x7)) != 0)
            |               ^
      
      ipv6_skip_exthdr() returns a signed integer.
      Reported-by: default avatarColin Ian King <colin.king@canonical.com>
      Fixes: 703acd70
      
       ("netfilter: nfnetlink_cthelper: unbreak userspace helper support")
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      987de40b
    • Qiushi Wu's avatar
      bonding: Fix reference count leak in bond_sysfs_slave_add. · a4547f63
      Qiushi Wu authored
      commit a068aab4 upstream.
      
      kobject_init_and_add() takes reference even when it fails.
      If this function returns an error, kobject_put() must be called to
      properly clean up the memory associated with the object. Previous
      commit "b8eb7183" fixed a similar problem.
      
      Fixes: 07699f9a
      
       ("bonding: add sysfs /slave dir for bond slave devices.")
      Signed-off-by: default avatarQiushi Wu <wu000273@umn.edu>
      Acked-by: default avatarJay Vosburgh <jay.vosburgh@canonical.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      a4547f63
    • Vladimir Oltean's avatar
      net: dsa: declare lockless TX feature for slave ports · b668b392
      Vladimir Oltean authored
      commit 2b86cb82 upstream.
      
      Be there a platform with the following layout:
      
            Regular NIC
             |
             +----> DSA master for switch port
                     |
                     +----> DSA master for another switch port
      
      After changing DSA back to static lockdep class keys in commit
      1a33e10e ("net: partially revert dynamic lockdep key changes"), this
      kernel splat can be seen:
      
      [   13.361198] ============================================
      [   13.366524] WARNING: possible recursive locking detected
      [   13.371851] 5.7.0-rc4-02121-gc32a05ecd7af-dirty #988 Not tainted
      [   13.377874] --------------------------------------------
      [   13.383201] swapper/0/0 is trying to acquire lock:
      [   13.388004] ffff0000668ff298 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
      [   13.397879]
      [   13.397879] but task is already holding lock:
      [   13.403727] ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
      [   13.413593]
      [   13.413593] other info that might help us debug this:
      [   13.420140]  Possible unsafe locking scenario:
      [   13.420140]
      [   13.426075]        CPU0
      [   13.428523]        ----
      [   13.430969]   lock(&dsa_slave_netdev_xmit_lock_key);
      [   13.435946]   lock(&dsa_slave_netdev_xmit_lock_key);
      [   13.440924]
      [   13.440924]  *** DEADLOCK ***
      [   13.440924]
      [   13.446860]  May be due to missing lock nesting notation
      [   13.446860]
      [   13.453668] 6 locks held by swapper/0/0:
      [   13.457598]  #0: ffff800010003de0 ((&idev->mc_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0x0/0x400
      [   13.466593]  #1: ffffd4d3fb478700 (rcu_read_lock){....}-{1:2}, at: mld_sendpack+0x0/0x560
      [   13.474803]  #2: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: ip6_finish_output2+0x64/0xb10
      [   13.483886]  #3: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0
      [   13.492793]  #4: ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
      [   13.503094]  #5: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0
      [   13.512000]
      [   13.512000] stack backtrace:
      [   13.516369] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc4-02121-gc32a05ecd7af-dirty #988
      [   13.530421] Call trace:
      [   13.532871]  dump_backtrace+0x0/0x1d8
      [   13.536539]  show_stack+0x24/0x30
      [   13.539862]  dump_stack+0xe8/0x150
      [   13.543271]  __lock_acquire+0x1030/0x1678
      [   13.547290]  lock_acquire+0xf8/0x458
      [   13.550873]  _raw_spin_lock+0x44/0x58
      [   13.554543]  __dev_queue_xmit+0x84c/0xbe0
      [   13.558562]  dev_queue_xmit+0x24/0x30
      [   13.562232]  dsa_slave_xmit+0xe0/0x128
      [   13.565988]  dev_hard_start_xmit+0xf4/0x448
      [   13.570182]  __dev_queue_xmit+0x808/0xbe0
      [   13.574200]  dev_queue_xmit+0x24/0x30
      [   13.577869]  neigh_resolve_output+0x15c/0x220
      [   13.582237]  ip6_finish_output2+0x244/0xb10
      [   13.586430]  __ip6_finish_output+0x1dc/0x298
      [   13.590709]  ip6_output+0x84/0x358
      [   13.594116]  mld_sendpack+0x2bc/0x560
      [   13.597786]  mld_ifc_timer_expire+0x210/0x390
      [   13.602153]  call_timer_fn+0xcc/0x400
      [   13.605822]  run_timer_softirq+0x588/0x6e0
      [   13.609927]  __do_softirq+0x118/0x590
      [   13.613597]  irq_exit+0x13c/0x148
      [   13.616918]  __handle_domain_irq+0x6c/0xc0
      [   13.621023]  gic_handle_irq+0x6c/0x160
      [   13.624779]  el1_irq+0xbc/0x180
      [   13.627927]  cpuidle_enter_state+0xb4/0x4d0
      [   13.632120]  cpuidle_enter+0x3c/0x50
      [   13.635703]  call_cpuidle+0x44/0x78
      [   13.639199]  do_idle+0x228/0x2c8
      [   13.642433]  cpu_startup_entry+0x2c/0x48
      [   13.646363]  rest_init+0x1ac/0x280
      [   13.649773]  arch_call_rest_init+0x14/0x1c
      [   13.653878]  start_kernel+0x490/0x4bc
      
      Lockdep keys themselves were added in commit ab92d68f ("net: core:
      add generic lockdep keys"), and it's very likely that this splat existed
      since then, but I have no real way to check, since this stacked platform
      wasn't supported by mainline back then.
      
      >From Taehee's own words:
      
        This patch was considered that all stackable devices have LLTX flag.
        But the dsa doesn't have LLTX, so this splat happened.
        After this patch, dsa shares the same lockdep class key.
        On the nested dsa interface architecture, which you illustrated,
        the same lockdep class key will be used in __dev_queue_xmit() because
        dsa doesn't have LLTX.
        So that lockdep detects deadlock because the same lockdep class key is
        used recursively although actually the different locks are used.
        There are some ways to fix this problem.
      
        1. using NETIF_F_LLTX flag.
        If possible, using the LLTX flag is a very clear way for it.
        But I'm so sorry I don't know whether the dsa could have LLTX or not.
      
        2. using dynamic lockdep again.
        It means that each interface uses a separate lockdep class key.
        So, lockdep will not detect recursive locking.
        But this way has a problem that it could consume lockdep class key
        too many.
        Currently, lockdep can have 8192 lockdep class keys.
         - you can see this number with the following command.
           cat /proc/lockdep_stats
           lock-classes:                         1251 [max: 8192]
           ...
           The [max: 8192] means that the maximum number of lockdep class keys.
        If too many lockdep class keys are registered, lockdep stops to work.
        So, using a dynamic(separated) lockdep class key should be considered
        carefully.
        In addition, updating lockdep class key routine might have to be existing.
        (lockdep_register_key(), lockdep_set_class(), lockdep_unregister_key())
      
        3. Using lockdep subclass.
        A lockdep class key could have 8 subclasses.
        The different subclass is considered different locks by lockdep
        infrastructure.
        But "lock-classes" is not counted by subclasses.
        So, it could avoid stopping lockdep infrastructure by an overflow of
        lockdep class keys.
        This approach should also have an updating lockdep class key routine.
        (lockdep_set_subclass())
      
        4. Using nonvalidate lockdep class key.
        The lockdep infrastructure supports nonvalidate lockdep class key type.
        It means this lockdep is not validated by lockdep infrastructure.
        So, the splat will not happen but lockdep couldn't detect real deadlock
        case because lockdep really doesn't validate it.
        I think this should be used for really special cases.
        (lockdep_set_novalidate_class())
      
      Further discussion here:
      https://patchwork.ozlabs.org/project/netdev/patch/20200503052220.4536-2-xiyou.wangcong@gmail.com/
      
      There appears to be no negative side-effect to declaring lockless TX for
      the DSA virtual interfaces, which means they handle their own locking.
      So that's what we do to make the splat go away.
      
      Patch tested in a wide variety of cases: unicast, multicast, PTP, etc.
      
      Fixes: ab92d68f
      
       ("net: core: add generic lockdep keys")
      Suggested-by: default avatarTaehee Yoo <ap420073@gmail.com>
      Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
      Reviewed-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b668b392