1. 16 Aug, 2017 12 commits
    • Miquel Raynal's avatar
      nand: fix wrong default oob layout for small pages using soft ecc · 160c365b
      Miquel Raynal authored
      commit f7f8c175 upstream.
      
      When using soft ecc, if no ooblayout is given, the core automatically
      uses one of the nand_ooblayout_{sp,lp}*() functions to determine the
      layout inside the out of band data.
      
      Until kernel version 4.6, struct nand_ecclayout was used for that
      purpose. During the migration from 4.6 to 4.7, an error shown up in the
      small page layout, in the case oob section is only 8 bytes long.
      
      The layout was using three bytes (0, 1, 2) for ecc, two bytes (3, 4)
      as free bytes, one byte (5) for bad block marker and finally
      two bytes (6, 7) as free bytes, as shown there:
      
      [linux-4.6] drivers/mtd/nand/nand_base.c:52
      static struct nand_ecclayout nand_oob_8 = {
      	.eccbytes = 3,
      	.eccpos = {0, 1, 2},
      	.oobfree = {
      		{.offset = 3,
      		 .length = 2},
      		{.offset = 6,
      		 .length = 2} }
      };
      
      This fixes the current implementation which is incoherent. It
      references bit 3 at the same time as an ecc byte and a free byte.
      
      Furthermore, it is clear with the previous implementation that there
      is only one ecc section with 8 bytes oob sections. We shall return
      -ERANGE in the nand_ooblayout_ecc_sp() function when asked for the
      second section.
      Signed-off-by: default avatarMiquel Raynal <miquel.raynal@free-electrons.com>
      Fixes: 41b207a7 ("mtd: nand: implement the default mtd_ooblayout_ops")
      Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      160c365b
    • Mateusz Jurczyk's avatar
      fuse: initialize the flock flag in fuse_file on allocation · 227559e6
      Mateusz Jurczyk authored
      commit 68227c03 upstream.
      
      Before the patch, the flock flag could remain uninitialized for the
      lifespan of the fuse_file allocation. Unless set to true in
      fuse_file_flock(), it would remain in an indeterminate state until read in
      an if statement in fuse_release_common(). This could consequently lead to
      taking an unexpected branch in the code.
      
      The bug was discovered by a runtime instrumentation designed to detect use
      of uninitialized memory in the kernel.
      Signed-off-by: default avatarMateusz Jurczyk <mjurczyk@google.com>
      Fixes: 37fb3a30 ("fuse: fix flock")
      Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      227559e6
    • Nicholas Bellinger's avatar
      target: Fix node_acl demo-mode + uncached dynamic shutdown regression · 1da30c23
      Nicholas Bellinger authored
      commit 6f48655f upstream.
      
      This patch fixes a generate_node_acls = 1 + cache_dynamic_acls = 0
      regression, that was introduced by
      
        commit 01d4d673
        Author: Nicholas Bellinger <nab@linux-iscsi.org>
        Date:   Wed Dec 7 12:55:54 2016 -0800
      
      which originally had the proper list_del_init() usage, but was
      dropped during list review as it was thought unnecessary by HCH.
      
      However, list_del_init() usage is required during the special
      generate_node_acls = 1 + cache_dynamic_acls = 0 case when
      transport_free_session() does a list_del(&se_nacl->acl_list),
      followed by target_complete_nacl() doing the same thing.
      
      This was manifesting as a general protection fault as reported
      by Justin:
      
      kernel: general protection fault: 0000 [#1] SMP
      kernel: Modules linked in:
      kernel: CPU: 0 PID: 11047 Comm: iscsi_ttx Not tainted 4.13.0-rc2.x86_64.1+ #20
      kernel: Hardware name: Intel Corporation S5500BC/S5500BC, BIOS S5500.86B.01.00.0064.050520141428 05/05/2014
      kernel: task: ffff88026939e800 task.stack: ffffc90007884000
      kernel: RIP: 0010:target_put_nacl+0x49/0xb0
      kernel: RSP: 0018:ffffc90007887d70 EFLAGS: 00010246
      kernel: RAX: dead000000000200 RBX: ffff8802556ca000 RCX: 0000000000000000
      kernel: RDX: dead000000000100 RSI: 0000000000000246 RDI: ffff8802556ce028
      kernel: RBP: ffffc90007887d88 R08: 0000000000000001 R09: 0000000000000000
      kernel: R10: ffffc90007887df8 R11: ffffea0009986900 R12: ffff8802556ce020
      kernel: R13: ffff8802556ce028 R14: ffff8802556ce028 R15: ffffffff88d85540
      kernel: FS:  0000000000000000(0000) GS:ffff88027fc00000(0000) knlGS:0000000000000000
      kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      kernel: CR2: 00007fffe36f5f94 CR3: 0000000009209000 CR4: 00000000003406f0
      kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      kernel: Call Trace:
      kernel:  transport_free_session+0x67/0x140
      kernel:  transport_deregister_session+0x7a/0xc0
      kernel:  iscsit_close_session+0x92/0x210
      kernel:  iscsit_close_connection+0x5f9/0x840
      kernel:  iscsit_take_action_for_connection_exit+0xfe/0x110
      kernel:  iscsi_target_tx_thread+0x140/0x1e0
      kernel:  ? wait_woken+0x90/0x90
      kernel:  kthread+0x124/0x160
      kernel:  ? iscsit_thread_get_cpumask+0x90/0x90
      kernel:  ? kthread_create_on_node+0x40/0x40
      kernel:  ret_from_fork+0x22/0x30
      kernel: Code: 00 48 89 fb 4c 8b a7 48 01 00 00 74 68 4d 8d 6c 24 08 4c
      89 ef e8 e8 28 43 00 48 8b 93 20 04 00 00 48 8b 83 28 04 00 00 4c 89
      ef <48> 89 42 08 48 89 10 48 b8 00 01 00 00 00 00 ad de 48 89 83 20
      kernel: RIP: target_put_nacl+0x49/0xb0 RSP: ffffc90007887d70
      kernel: ---[ end trace f12821adbfd46fed ]---
      
      To address this, go ahead and use proper list_del_list() for all
      cases of se_nacl->acl_list deletion.
      Reported-by: default avatarJustin Maggard <jmaggard01@gmail.com>
      Tested-by: default avatarJustin Maggard <jmaggard01@gmail.com>
      Cc: Justin Maggard <jmaggard01@gmail.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1da30c23
    • Nicholas Bellinger's avatar
      iscsi-target: Fix iscsi_np reset hung task during parallel delete · b51a7163
      Nicholas Bellinger authored
      commit 978d13d6 upstream.
      
      This patch fixes a bug associated with iscsit_reset_np_thread()
      that can occur during parallel configfs rmdir of a single iscsi_np
      used across multiple iscsi-target instances, that would result in
      hung task(s) similar to below where configfs rmdir process context
      was blocked indefinately waiting for iscsi_np->np_restart_comp
      to finish:
      
      [ 6726.112076] INFO: task dcp_proxy_node_:15550 blocked for more than 120 seconds.
      [ 6726.119440]       Tainted: G        W  O     4.1.26-3321 #2
      [ 6726.125045] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
      [ 6726.132927] dcp_proxy_node_ D ffff8803f202bc88     0 15550      1 0x00000000
      [ 6726.140058]  ffff8803f202bc88 ffff88085c64d960 ffff88083b3b1ad0 ffff88087fffeb08
      [ 6726.147593]  ffff8803f202c000 7fffffffffffffff ffff88083f459c28 ffff88083b3b1ad0
      [ 6726.155132]  ffff88035373c100 ffff8803f202bca8 ffffffff8168ced2 ffff8803f202bcb8
      [ 6726.162667] Call Trace:
      [ 6726.165150]  [<ffffffff8168ced2>] schedule+0x32/0x80
      [ 6726.170156]  [<ffffffff8168f5b4>] schedule_timeout+0x214/0x290
      [ 6726.176030]  [<ffffffff810caef2>] ? __send_signal+0x52/0x4a0
      [ 6726.181728]  [<ffffffff8168d7d6>] wait_for_completion+0x96/0x100
      [ 6726.187774]  [<ffffffff810e7c80>] ? wake_up_state+0x10/0x10
      [ 6726.193395]  [<ffffffffa035d6e2>] iscsit_reset_np_thread+0x62/0xe0 [iscsi_target_mod]
      [ 6726.201278]  [<ffffffffa0355d86>] iscsit_tpg_disable_portal_group+0x96/0x190 [iscsi_target_mod]
      [ 6726.210033]  [<ffffffffa0363f7f>] lio_target_tpg_store_enable+0x4f/0xc0 [iscsi_target_mod]
      [ 6726.218351]  [<ffffffff81260c5a>] configfs_write_file+0xaa/0x110
      [ 6726.224392]  [<ffffffff811ea364>] vfs_write+0xa4/0x1b0
      [ 6726.229576]  [<ffffffff811eb111>] SyS_write+0x41/0xb0
      [ 6726.234659]  [<ffffffff8169042e>] system_call_fastpath+0x12/0x71
      
      It would happen because each iscsit_reset_np_thread() sets state
      to ISCSI_NP_THREAD_RESET, sends SIGINT, and then blocks waiting
      for completion on iscsi_np->np_restart_comp.
      
      However, if iscsi_np was active processing a login request and
      more than a single iscsit_reset_np_thread() caller to the same
      iscsi_np was blocked on iscsi_np->np_restart_comp, iscsi_np
      kthread process context in __iscsi_target_login_thread() would
      flush pending signals and only perform a single completion of
      np->np_restart_comp before going back to sleep within transport
      specific iscsit_transport->iscsi_accept_np code.
      
      To address this bug, add a iscsi_np->np_reset_count and update
      __iscsi_target_login_thread() to keep completing np->np_restart_comp
      until ->np_reset_count has reached zero.
      Reported-by: default avatarGary Guo <ghg@datera.io>
      Tested-by: default avatarGary Guo <ghg@datera.io>
      Cc: Mike Christie <mchristi@redhat.com>
      Cc: Hannes Reinecke <hare@suse.de>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b51a7163
    • Varun Prakash's avatar
      iscsi-target: fix memory leak in iscsit_setup_text_cmd() · e6a0599b
      Varun Prakash authored
      commit ea8dc5b4 upstream.
      
      On receiving text request iscsi-target allocates buffer for
      payload in iscsit_handle_text_cmd() and assigns buffer pointer
      to cmd->text_in_ptr, this buffer is currently freed in
      iscsit_release_cmd(), if iscsi-target sets 'C' bit in text
      response then it will receive another text request from the
      initiator with ttt != 0xffffffff in this case iscsi-target
      will find cmd using itt and call iscsit_setup_text_cmd()
      which will set cmd->text_in_ptr to NULL without freeing
      previously allocated buffer.
      
      This patch fixes this issue by calling kfree(cmd->text_in_ptr)
      in iscsit_setup_text_cmd() before assigning NULL to it.
      
      For the first text request cmd->text_in_ptr is NULL as
      cmd is memset to 0 in iscsit_allocate_cmd().
      Signed-off-by: default avatarVarun Prakash <varun@chelsio.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e6a0599b
    • Boris Brezillon's avatar
      mtd: nand: Fix timing setup for NANDs that do not support SET FEATURES · ced271b8
      Boris Brezillon authored
      commit a11bf5ed upstream.
      
      Some ONFI NANDs do not support the SET/GET FEATURES commands, which,
      according to the spec, is perfectly valid.
      
      On these NANDs we can't set a specific timing mode using the "timing
      mode" feature, and we should assume the NAND does not require any setup
      to enter a specific timing mode.
      Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
      Fixes: d8e725dd ("mtd: nand: automate NAND timings selection")
      Reported-by: default avatarAlexander Dahl <ada@thorsis.com>
      Tested-by: default avatarAlexander Dahl <ada@thorsis.com>
      Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      ced271b8
    • Max Filippov's avatar
      xtensa: don't limit csum_partial export by CONFIG_NET · a3118109
      Max Filippov authored
      commit 7f81e55c upstream.
      
      csum_partial and csum_partial_copy_generic are defined unconditionally
      and are available even when CONFIG_NET is disabled. They are used not
      only by the network drivers, but also by scsi and media.
      Don't limit these functions export by CONFIG_NET.
      Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      a3118109
    • Max Filippov's avatar
      xtensa: mm/cache: add missing EXPORT_SYMBOLs · a3ab0f06
      Max Filippov authored
      commit bc652eb6 upstream.
      
      Functions clear_user_highpage, copy_user_highpage, flush_dcache_page,
      local_flush_cache_range and local_flush_cache_page may be used from
      modules. Export them.
      Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      a3ab0f06
    • Max Filippov's avatar
      xtensa: fix cache aliasing handling code for WT cache · 03973c57
      Max Filippov authored
      commit 6d0f581d upstream.
      
      Currently building kernel for xtensa core with aliasing WT cache fails
      with the following messages:
      
        mm/memory.c:2152: undefined reference to `flush_dcache_page'
        mm/memory.c:2332: undefined reference to `local_flush_cache_page'
        mm/memory.c:1919: undefined reference to `local_flush_cache_range'
        mm/memory.c:4179: undefined reference to `copy_to_user_page'
        mm/memory.c:4183: undefined reference to `copy_from_user_page'
      
      This happens because implementation of these functions is only compiled
      when data cache is WB, which looks wrong: even when data cache doesn't
      need flushing it still needs invalidation. The functions like
      __flush_[invalidate_]dcache_* are correctly defined for both WB and WT
      caches (and even if they weren't that'd still be ok, just slower).
      
      Fix this by providing the same implementation of the above functions for
      both WB and WT cache.
      Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      03973c57
    • Mel Gorman's avatar
      futex: Remove unnecessary warning from get_futex_key · 0041042d
      Mel Gorman authored
      commit 48fb6f4d upstream.
      
      Commit 65d8fc77 ("futex: Remove requirement for lock_page() in
      get_futex_key()") removed an unnecessary lock_page() with the
      side-effect that page->mapping needed to be treated very carefully.
      
      Two defensive warnings were added in case any assumption was missed and
      the first warning assumed a correct application would not alter a
      mapping backing a futex key.  Since merging, it has not triggered for
      any unexpected case but Mark Rutland reported the following bug
      triggering due to the first warning.
      
        kernel BUG at kernel/futex.c:679!
        Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
        Modules linked in:
        CPU: 0 PID: 3695 Comm: syz-executor1 Not tainted 4.13.0-rc3-00020-g307fec773ba3 #3
        Hardware name: linux,dummy-virt (DT)
        task: ffff80001e271780 task.stack: ffff000010908000
        PC is at get_futex_key+0x6a4/0xcf0 kernel/futex.c:679
        LR is at get_futex_key+0x6a4/0xcf0 kernel/futex.c:679
        pc : [<ffff00000821ac14>] lr : [<ffff00000821ac14>] pstate: 80000145
      
      The fact that it's a bug instead of a warning was due to an unrelated
      arm64 problem, but the warning itself triggered because the underlying
      mapping changed.
      
      This is an application issue but from a kernel perspective it's a
      recoverable situation and the warning is unnecessary so this patch
      removes the warning.  The warning may potentially be triggered with the
      following test program from Mark although it may be necessary to adjust
      NR_FUTEX_THREADS to be a value smaller than the number of CPUs in the
      system.
      
          #include <linux/futex.h>
          #include <pthread.h>
          #include <stdio.h>
          #include <stdlib.h>
          #include <sys/mman.h>
          #include <sys/syscall.h>
          #include <sys/time.h>
          #include <unistd.h>
      
          #define NR_FUTEX_THREADS 16
          pthread_t threads[NR_FUTEX_THREADS];
      
          void *mem;
      
          #define MEM_PROT  (PROT_READ | PROT_WRITE)
          #define MEM_SIZE  65536
      
          static int futex_wrapper(int *uaddr, int op, int val,
                                   const struct timespec *timeout,
                                   int *uaddr2, int val3)
          {
              syscall(SYS_futex, uaddr, op, val, timeout, uaddr2, val3);
          }
      
          void *poll_futex(void *unused)
          {
              for (;;) {
                  futex_wrapper(mem, FUTEX_CMP_REQUEUE_PI, 1, NULL, mem + 4, 1);
              }
          }
      
          int main(int argc, char *argv[])
          {
              int i;
      
              mem = mmap(NULL, MEM_SIZE, MEM_PROT,
                     MAP_SHARED | MAP_ANONYMOUS, -1, 0);
      
              printf("Mapping @ %p\n", mem);
      
              printf("Creating futex threads...\n");
      
              for (i = 0; i < NR_FUTEX_THREADS; i++)
                  pthread_create(&threads[i], NULL, poll_futex, NULL);
      
              printf("Flipping mapping...\n");
              for (;;) {
                  mmap(mem, MEM_SIZE, MEM_PROT,
                       MAP_FIXED | MAP_SHARED | MAP_ANONYMOUS, -1, 0);
              }
      
              return 0;
          }
      Reported-and-tested-by: default avatarMark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
      Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      0041042d
    • Cong Wang's avatar
      mm: fix list corruptions on shmem shrinklist · e2286916
      Cong Wang authored
      commit d041353d upstream.
      
      We saw many list corruption warnings on shmem shrinklist:
      
        WARNING: CPU: 18 PID: 177 at lib/list_debug.c:59 __list_del_entry+0x9e/0xc0
        list_del corruption. prev->next should be ffff9ae5694b82d8, but was ffff9ae5699ba960
        Modules linked in: intel_rapl sb_edac edac_core x86_pkg_temp_thermal coretemp iTCO_wdt iTCO_vendor_support crct10dif_pclmul crc32_pclmul ghash_clmulni_intel raid0 dcdbas shpchp wmi hed i2c_i801 ioatdma lpc_ich i2c_smbus acpi_cpufreq tcp_diag inet_diag sch_fq_codel ipmi_si ipmi_devintf ipmi_msghandler igb ptp crc32c_intel pps_core i2c_algo_bit i2c_core dca ipv6 crc_ccitt
        CPU: 18 PID: 177 Comm: kswapd1 Not tainted 4.9.34-t3.el7.twitter.x86_64 #1
        Hardware name: Dell Inc. PowerEdge C6220/0W6W6G, BIOS 2.2.3 11/07/2013
        Call Trace:
          dump_stack+0x4d/0x66
          __warn+0xcb/0xf0
          warn_slowpath_fmt+0x4f/0x60
          __list_del_entry+0x9e/0xc0
          shmem_unused_huge_shrink+0xfa/0x2e0
          shmem_unused_huge_scan+0x20/0x30
          super_cache_scan+0x193/0x1a0
          shrink_slab.part.41+0x1e3/0x3f0
          shrink_slab+0x29/0x30
          shrink_node+0xf9/0x2f0
          kswapd+0x2d8/0x6c0
          kthread+0xd7/0xf0
          ret_from_fork+0x22/0x30
      
        WARNING: CPU: 23 PID: 639 at lib/list_debug.c:33 __list_add+0x89/0xb0
        list_add corruption. prev->next should be next (ffff9ae5699ba960), but was ffff9ae5694b82d8. (prev=ffff9ae5694b82d8).
        Modules linked in: intel_rapl sb_edac edac_core x86_pkg_temp_thermal coretemp iTCO_wdt iTCO_vendor_support crct10dif_pclmul crc32_pclmul ghash_clmulni_intel raid0 dcdbas shpchp wmi hed i2c_i801 ioatdma lpc_ich i2c_smbus acpi_cpufreq tcp_diag inet_diag sch_fq_codel ipmi_si ipmi_devintf ipmi_msghandler igb ptp crc32c_intel pps_core i2c_algo_bit i2c_core dca ipv6 crc_ccitt
        CPU: 23 PID: 639 Comm: systemd-udevd Tainted: G        W       4.9.34-t3.el7.twitter.x86_64 #1
        Hardware name: Dell Inc. PowerEdge C6220/0W6W6G, BIOS 2.2.3 11/07/2013
        Call Trace:
          dump_stack+0x4d/0x66
          __warn+0xcb/0xf0
          warn_slowpath_fmt+0x4f/0x60
          __list_add+0x89/0xb0
          shmem_setattr+0x204/0x230
          notify_change+0x2ef/0x440
          do_truncate+0x5d/0x90
          path_openat+0x331/0x1190
          do_filp_open+0x7e/0xe0
          do_sys_open+0x123/0x200
          SyS_open+0x1e/0x20
          do_syscall_64+0x61/0x170
          entry_SYSCALL64_slow_path+0x25/0x25
      
      The problem is that shmem_unused_huge_shrink() moves entries from the
      global sbinfo->shrinklist to its local lists and then releases the
      spinlock.  However, a parallel shmem_setattr() could access one of these
      entries directly and add it back to the global shrinklist if it is
      removed, with the spinlock held.
      
      The logic itself looks solid since an entry could be either in a local
      list or the global list, otherwise it is removed from one of them by
      list_del_init().  So probably the race condition is that, one CPU is in
      the middle of INIT_LIST_HEAD() but the other CPU calls list_empty()
      which returns true too early then the following list_add_tail() sees a
      corrupted entry.
      
      list_empty_careful() is designed to fix this situation.
      
      [akpm@linux-foundation.org: add comments]
      Link: http://lkml.kernel.org/r/20170803054630.18775-1-xiyou.wangcong@gmail.com
      Fixes: 779750d2 ("shmem: split huge pages beyond i_size under memory pressure")
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Acked-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Hugh Dickins <hughd@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e2286916
    • Jonathan Toppins's avatar
      mm: ratelimit PFNs busy info message · b56cd77c
      Jonathan Toppins authored
      commit 75dddef3 upstream.
      
      The RDMA subsystem can generate several thousand of these messages per
      second eventually leading to a kernel crash.  Ratelimit these messages
      to prevent this crash.
      
      Doug said:
       "I've been carrying a version of this for several kernel versions. I
        don't remember when they started, but we have one (and only one) class
        of machines: Dell PE R730xd, that generate these errors. When it
        happens, without a rate limit, we get rcu timeouts and kernel oopses.
        With the rate limit, we just get a lot of annoying kernel messages but
        the machine continues on, recovers, and eventually the memory
        operations all succeed"
      
      And:
       "> Well... why are all these EBUSY's occurring? It sounds inefficient
        > (at least) but if it is expected, normal and unavoidable then
        > perhaps we should just remove that message altogether?
      
        I don't have an answer to that question. To be honest, I haven't
        looked real hard. We never had this at all, then it started out of the
        blue, but only on our Dell 730xd machines (and it hits all of them),
        but no other classes or brands of machines. And we have our 730xd
        machines loaded up with different brands and models of cards (for
        instance one dedicated to mlx4 hardware, one for qib, one for mlx5, an
        ocrdma/cxgb4 combo, etc), so the fact that it hit all of the machines
        meant it wasn't tied to any particular brand/model of RDMA hardware.
        To me, it always smelled of a hardware oddity specific to maybe the
        CPUs or mainboard chipsets in these machines, so given that I'm not an
        mm expert anyway, I never chased it down.
      
        A few other relevant details: it showed up somewhere around 4.8/4.9 or
        thereabouts. It never happened before, but the prinkt has been there
        since the 3.18 days, so possibly the test to trigger this message was
        changed, or something else in the allocator changed such that the
        situation started happening on these machines?
      
        And, like I said, it is specific to our 730xd machines (but they are
        all identical, so that could mean it's something like their specific
        ram configuration is causing the allocator to hit this on these
        machine but not on other machines in the cluster, I don't want to say
        it's necessarily the model of chipset or CPU, there are other bits of
        identicalness between these machines)"
      
      Link: http://lkml.kernel.org/r/499c0f6cc10d6eb829a67f2a4d75b4228a9b356e.1501695897.git.jtoppins@redhat.comSigned-off-by: default avatarJonathan Toppins <jtoppins@redhat.com>
      Reviewed-by: default avatarDoug Ledford <dledford@redhat.com>
      Tested-by: default avatarDoug Ledford <dledford@redhat.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b56cd77c
  2. 13 Aug, 2017 18 commits
    • Greg Kroah-Hartman's avatar
      Linux 4.9.43 · 6da35f43
      Greg Kroah-Hartman authored
      6da35f43
    • Greg Kroah-Hartman's avatar
      Revert "ARM: dts: sun8i: Support DTB build for NanoPi M1" · 1166e3e0
      Greg Kroah-Hartman authored
      This reverts commit 1e9e7178 which is
      commit 661ccdc1 upstream.
      
      It's not needed in 4.9, and it breaks the build.
      Reported-by: default avatarGuenter Roeck <linux@roeck-us.net>
      Cc: Milo Kim <woogyom.kim@gmail.com>
      Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
      Cc: Sasha Levin <alexander.levin@verizon.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1166e3e0
    • Suzuki K Poulose's avatar
      KVM: arm/arm64: Handle hva aging while destroying the vm · 3f0075cd
      Suzuki K Poulose authored
      commit 7e5a6722 upstream.
      
      The mmu_notifier_release() callback of KVM triggers cleaning up
      the stage2 page table on kvm-arm. However there could be other
      notifier callbacks in parallel with the mmu_notifier_release(),
      which could cause the call backs ending up in an empty stage2
      page table. Make sure we check it for all the notifier callbacks.
      
      Fixes: commit 293f2936 ("kvm-arm: Unmap shadow pagetables properly")
      Reported-by: default avatarAlex Graf <agraf@suse.de>
      Reviewed-by: default avatarChristoffer Dall <cdall@linaro.org>
      Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
      Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      
      3f0075cd
    • Rob Gardner's avatar
      sparc64: Prevent perf from running during super critical sections · 6309eb77
      Rob Gardner authored
      commit fc290a11 upstream.
      
      This fixes another cause of random segfaults and bus errors that may
      occur while running perf with the callgraph option.
      
      Critical sections beginning with spin_lock_irqsave() raise the interrupt
      level to PIL_NORMAL_MAX (14) and intentionally do not block performance
      counter interrupts, which arrive at PIL_NMI (15).
      
      But some sections of code are "super critical" with respect to perf
      because the perf_callchain_user() path accesses user space and may cause
      TLB activity as well as faults as it unwinds the user stack.
      
      One particular critical section occurs in switch_mm:
      
              spin_lock_irqsave(&mm->context.lock, flags);
              ...
              load_secondary_context(mm);
              tsb_context_switch(mm);
              ...
              spin_unlock_irqrestore(&mm->context.lock, flags);
      
      If a perf interrupt arrives in between load_secondary_context() and
      tsb_context_switch(), then perf_callchain_user() could execute with
      the context ID of one process, but with an active TSB for a different
      process. When the user stack is accessed, it is very likely to
      incur a TLB miss, since the h/w context ID has been changed. The TLB
      will then be reloaded with a translation from the TSB for one process,
      but using a context ID for another process. This exposes memory from
      one process to another, and since it is a mapping for stack memory,
      this usually causes the new process to crash quickly.
      
      This super critical section needs more protection than is provided
      by spin_lock_irqsave() since perf interrupts must not be allowed in.
      
      Since __tsb_context_switch already goes through the trouble of
      disabling interrupts completely, we fix this by moving the secondary
      context load down into this better protected region.
      
      Orabug: 25577560
      Signed-off-by: default avatarDave Aldridge <david.j.aldridge@oracle.com>
      Signed-off-by: default avatarRob Gardner <rob.gardner@oracle.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6309eb77
    • Willem de Bruijn's avatar
      udp: consistently apply ufo or fragmentation · 33dc6a6a
      Willem de Bruijn authored
      
      [ Upstream commit 85f1bd9a ]
      
      When iteratively building a UDP datagram with MSG_MORE and that
      datagram exceeds MTU, consistently choose UFO or fragmentation.
      
      Once skb_is_gso, always apply ufo. Conversely, once a datagram is
      split across multiple skbs, do not consider ufo.
      
      Sendpage already maintains the first invariant, only add the second.
      IPv6 does not have a sendpage implementation to modify.
      
      A gso skb must have a partial checksum, do not follow sk_no_check_tx
      in udp_send_skb.
      
      Found by syzkaller.
      
      Fixes: e89e9cf5 ("[IPv4/IPv6]: UFO Scatter-gather approach")
      Reported-by: default avatarAndrey Konovalov <andreyknvl@google.com>
      Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      33dc6a6a
    • Greg Kroah-Hartman's avatar
      revert "ipv4: Should use consistent conditional judgement for ip fragment in... · 4688f042
      Greg Kroah-Hartman authored
      revert "ipv4: Should use consistent conditional judgement for ip fragment in __ip_append_data and ip_finish_output"
      
      This reverts commit f102bb71 which is
      commit 0a28cfd5 upstream as there is
      another patch that needs to be applied instead of this one.
      
      Cc: Zheng Li <james.z.li@ericsson.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Sasha Levin <alexander.levin@verizon.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      
      4688f042
    • Greg Kroah-Hartman's avatar
      revert "net: account for current skb length when deciding about UFO" · 53eed8aa
      Greg Kroah-Hartman authored
      This reverts commit ef09c9ff which is
      commit a5cb659b upstream as it causes
      merge issues with later patches that are much more important...
      
      Cc: Michal Kubecek <mkubecek@suse.cz>
      Cc: Vlad Yasevich <vyasevic@redhat.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Sasha Levin <alexander.levin@verizon.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      53eed8aa
    • Willem de Bruijn's avatar
      packet: fix tp_reserve race in packet_set_ring · e5841355
      Willem de Bruijn authored
      
      [ Upstream commit c27927e3 ]
      
      Updates to tp_reserve can race with reads of the field in
      packet_set_ring. Avoid this by holding the socket lock during
      updates in setsockopt PACKET_RESERVE.
      
      This bug was discovered by syzkaller.
      
      Fixes: 8913336a ("packet: add PACKET_RESERVE sockopt")
      Reported-by: default avatarAndrey Konovalov <andreyknvl@google.com>
      Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e5841355
    • Nikolay Borisov's avatar
      igmp: Fix regression caused by igmp sysctl namespace code. · f628c9df
      Nikolay Borisov authored
      
      [ Upstream commit 1714020e ]
      
      Commit dcd87999 ("igmp: net: Move igmp namespace init to correct file")
      moved the igmp sysctls initialization from tcp_sk_init to igmp_net_init. This
      function is only called as part of per-namespace initialization, only if
      CONFIG_IP_MULTICAST is defined, otherwise igmp_mc_init() call in ip_init is
      compiled out, casuing the igmp pernet ops to not be registerd and those sysctl
      being left initialized with 0. However, there are certain functions, such as
      ip_mc_join_group which are always compiled and make use of some of those
      sysctls. Let's do a partial revert of the aforementioned commit and move the
      sysctl initialization into inet_init_net, that way they will always have
      sane values.
      
      Fixes: dcd87999 ("igmp: net: Move igmp namespace init to correct file")
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=196595Reported-by: default avatarGerardo Exequiel Pozzi <vmlinuz386@gmail.com>
      Signed-off-by: default avatarNikolay Borisov <nborisov@suse.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      f628c9df
    • Willem de Bruijn's avatar
      net: avoid skb_warn_bad_offload false positives on UFO · 69ffc964
      Willem de Bruijn authored
      
      [ Upstream commit 8d63bee6 ]
      
      skb_warn_bad_offload triggers a warning when an skb enters the GSO
      stack at __skb_gso_segment that does not have CHECKSUM_PARTIAL
      checksum offload set.
      
      Commit b2504a5d ("net: reduce skb_warn_bad_offload() noise")
      observed that SKB_GSO_DODGY producers can trigger the check and
      that passing those packets through the GSO handlers will fix it
      up. But, the software UFO handler will set ip_summed to
      CHECKSUM_NONE.
      
      When __skb_gso_segment is called from the receive path, this
      triggers the warning again.
      
      Make UFO set CHECKSUM_UNNECESSARY instead of CHECKSUM_NONE. On
      Tx these two are equivalent. On Rx, this better matches the
      skb state (checksum computed), as CHECKSUM_NONE here means no
      checksum computed.
      
      See also this thread for context:
      http://patchwork.ozlabs.org/patch/799015/
      
      Fixes: b2504a5d ("net: reduce skb_warn_bad_offload() noise")
      Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      69ffc964
    • Eric Dumazet's avatar
      tcp: fastopen: tcp_connect() must refresh the route · 87fdcfe2
      Eric Dumazet authored
      
      [ Upstream commit 8ba60924 ]
      
      With new TCP_FASTOPEN_CONNECT socket option, there is a possibility
      to call tcp_connect() while socket sk_dst_cache is either NULL
      or invalid.
      
       +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 4
       +0 fcntl(4, F_SETFL, O_RDWR|O_NONBLOCK) = 0
       +0 setsockopt(4, SOL_TCP, TCP_FASTOPEN_CONNECT, [1], 4) = 0
       +0 connect(4, ..., ...) = 0
      
      << sk->sk_dst_cache becomes obsolete, or even set to NULL >>
      
       +1 sendto(4, ..., 1000, MSG_FASTOPEN, ..., ...) = 1000
      
      We need to refresh the route otherwise bad things can happen,
      especially when syzkaller is running on the host :/
      
      Fixes: 19f6d3f3 ("net/tcp-fastopen: Add new API support")
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Wei Wang <weiwan@google.com>
      Cc: Yuchung Cheng <ycheng@google.com>
      Acked-by: default avatarWei Wang <weiwan@google.com>
      Acked-by: default avatarYuchung Cheng <ycheng@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      87fdcfe2
    • Xin Long's avatar
      net: sched: set xt_tgchk_param par.nft_compat as 0 in ipt_init_target · e392e305
      Xin Long authored
      
      [ Upstream commit 96d97030 ]
      
      Commit 55917a21 ("netfilter: x_tables: add context to know if
      extension runs from nft_compat") introduced a member nft_compat to
      xt_tgchk_param structure.
      
      But it didn't set it's value for ipt_init_target. With unexpected
      value in par.nft_compat, it may return unexpected result in some
      target's checkentry.
      
      This patch is to set all it's fields as 0 and only initialize the
      non-zero fields in ipt_init_target.
      
      v1->v2:
        As Wang Cong's suggestion, fix it by setting all it's fields as
        0 and only initializing the non-zero fields.
      
      Fixes: 55917a21 ("netfilter: x_tables: add context to know if extension runs from nft_compat")
      Suggested-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e392e305
    • Davide Caratti's avatar
      net/mlx4_en: don't set CHECKSUM_COMPLETE on SCTP packets · 35d90144
      Davide Caratti authored
      
      [ Upstream commit e718fe45 ]
      
      if the NIC fails to validate the checksum on TCP/UDP, and validation of IP
      checksum is successful, the driver subtracts the pseudo-header checksum
      from the value obtained by the hardware and sets CHECKSUM_COMPLETE. Don't
      do that if protocol is IPPROTO_SCTP, otherwise CRC32c validation fails.
      
      V2: don't test MLX4_CQE_STATUS_IPV6 if MLX4_CQE_STATUS_IPV4 is set
      Reported-by: default avatarShuang Li <shuali@redhat.com>
      Fixes: f8c6455b ("net/mlx4_en: Extend checksum offloading by CHECKSUM COMPLETE")
      Signed-off-by: default avatarDavide Caratti <dcaratti@redhat.com>
      Acked-by: default avatarSaeed Mahameed <saeedm@mellanox.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      35d90144
    • Daniel Borkmann's avatar
      bpf, s390: fix jit branch offset related to ldimm64 · 1b582a2c
      Daniel Borkmann authored
      
      [ Upstream commit b0a0c256 ]
      
      While testing some other work that required JIT modifications, I
      run into test_bpf causing a hang when JIT enabled on s390. The
      problematic test case was the one from ddc665a4 (bpf, arm64:
      fix jit branch offset related to ldimm64), and turns out that we
      do have a similar issue on s390 as well. In bpf_jit_prog() we
      update next instruction address after returning from bpf_jit_insn()
      with an insn_count. bpf_jit_insn() returns either -1 in case of
      error (e.g. unsupported insn), 1 or 2. The latter is only the
      case for ldimm64 due to spanning 2 insns, however, next address
      is only set to i + 1 not taking actual insn_count into account,
      thus fix is to use insn_count instead of 1. bpf_jit_enable in
      mode 2 provides also disasm on s390:
      
      Before fix:
      
        000003ff800349b6: a7f40003   brc     15,3ff800349bc                 ; target
        000003ff800349ba: 0000               unknown
        000003ff800349bc: e3b0f0700024       stg     %r11,112(%r15)
        000003ff800349c2: e3e0f0880024       stg     %r14,136(%r15)
        000003ff800349c8: 0db0               basr    %r11,%r0
        000003ff800349ca: c0ef00000000       llilf   %r14,0
        000003ff800349d0: e320b0360004       lg      %r2,54(%r11)
        000003ff800349d6: e330b03e0004       lg      %r3,62(%r11)
        000003ff800349dc: ec23ffeda065       clgrj   %r2,%r3,10,3ff800349b6 ; jmp
        000003ff800349e2: e3e0b0460004       lg      %r14,70(%r11)
        000003ff800349e8: e3e0b04e0004       lg      %r14,78(%r11)
        000003ff800349ee: b904002e   lgr     %r2,%r14
        000003ff800349f2: e3b0f0700004       lg      %r11,112(%r15)
        000003ff800349f8: e3e0f0880004       lg      %r14,136(%r15)
        000003ff800349fe: 07fe               bcr     15,%r14
      
      After fix:
      
        000003ff80ef3db4: a7f40003   brc     15,3ff80ef3dba
        000003ff80ef3db8: 0000               unknown
        000003ff80ef3dba: e3b0f0700024       stg     %r11,112(%r15)
        000003ff80ef3dc0: e3e0f0880024       stg     %r14,136(%r15)
        000003ff80ef3dc6: 0db0               basr    %r11,%r0
        000003ff80ef3dc8: c0ef00000000       llilf   %r14,0
        000003ff80ef3dce: e320b0360004       lg      %r2,54(%r11)
        000003ff80ef3dd4: e330b03e0004       lg      %r3,62(%r11)
        000003ff80ef3dda: ec230006a065       clgrj   %r2,%r3,10,3ff80ef3de6 ; jmp
        000003ff80ef3de0: e3e0b0460004       lg      %r14,70(%r11)
        000003ff80ef3de6: e3e0b04e0004       lg      %r14,78(%r11)          ; target
        000003ff80ef3dec: b904002e   lgr     %r2,%r14
        000003ff80ef3df0: e3b0f0700004       lg      %r11,112(%r15)
        000003ff80ef3df6: e3e0f0880004       lg      %r14,136(%r15)
        000003ff80ef3dfc: 07fe               bcr     15,%r14
      
      test_bpf.ko suite runs fine after the fix.
      
      Fixes: 05462310 ("s390/bpf: Add s390x eBPF JIT compiler backend")
      Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
      Tested-by: default avatarMichael Holzheu <holzheu@linux.vnet.ibm.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1b582a2c
    • Eric Dumazet's avatar
      net: fix keepalive code vs TCP_FASTOPEN_CONNECT · 05046af3
      Eric Dumazet authored
      
      [ Upstream commit 2dda6400 ]
      
      syzkaller was able to trigger a divide by 0 in TCP stack [1]
      
      Issue here is that keepalive timer needs to be updated to not attempt
      to send a probe if the connection setup was deferred using
      TCP_FASTOPEN_CONNECT socket option added in linux-4.11
      
      [1]
       divide error: 0000 [#1] SMP
       CPU: 18 PID: 0 Comm: swapper/18 Not tainted
       task: ffff986f62f4b040 ti: ffff986f62fa2000 task.ti: ffff986f62fa2000
       RIP: 0010:[<ffffffff8409cc0d>]  [<ffffffff8409cc0d>] __tcp_select_window+0x8d/0x160
       Call Trace:
        <IRQ>
        [<ffffffff8409d951>] tcp_transmit_skb+0x11/0x20
        [<ffffffff8409da21>] tcp_xmit_probe_skb+0xc1/0xe0
        [<ffffffff840a0ee8>] tcp_write_wakeup+0x68/0x160
        [<ffffffff840a151b>] tcp_keepalive_timer+0x17b/0x230
        [<ffffffff83b3f799>] call_timer_fn+0x39/0xf0
        [<ffffffff83b40797>] run_timer_softirq+0x1d7/0x280
        [<ffffffff83a04ddb>] __do_softirq+0xcb/0x257
        [<ffffffff83ae03ac>] irq_exit+0x9c/0xb0
        [<ffffffff83a04c1a>] smp_apic_timer_interrupt+0x6a/0x80
        [<ffffffff83a03eaf>] apic_timer_interrupt+0x7f/0x90
        <EOI>
        [<ffffffff83fed2ea>] ? cpuidle_enter_state+0x13a/0x3b0
        [<ffffffff83fed2cd>] ? cpuidle_enter_state+0x11d/0x3b0
      
      Tested:
      
      Following packetdrill no longer crashes the kernel
      
      `echo 0 >/proc/sys/net/ipv4/tcp_timestamps`
      
      // Cache warmup: send a Fast Open cookie request
          0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
         +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0
         +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN_CONNECT, [1], 4) = 0
         +0 connect(3, ..., ...) = -1 EINPROGRESS (Operation is now in progress)
         +0 > S 0:0(0) <mss 1460,nop,nop,sackOK,nop,wscale 8,FO,nop,nop>
       +.01 < S. 123:123(0) ack 1 win 14600 <mss 1460,nop,nop,sackOK,nop,wscale 6,FO abcd1234,nop,nop>
         +0 > . 1:1(0) ack 1
         +0 close(3) = 0
         +0 > F. 1:1(0) ack 1
         +0 < F. 1:1(0) ack 2 win 92
         +0 > .  2:2(0) ack 2
      
         +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 4
         +0 fcntl(4, F_SETFL, O_RDWR|O_NONBLOCK) = 0
         +0 setsockopt(4, SOL_TCP, TCP_FASTOPEN_CONNECT, [1], 4) = 0
         +0 setsockopt(4, SOL_SOCKET, SO_KEEPALIVE, [1], 4) = 0
       +.01 connect(4, ..., ...) = 0
         +0 setsockopt(4, SOL_TCP, TCP_KEEPIDLE, [5], 4) = 0
         +10 close(4) = 0
      
      `echo 1 >/proc/sys/net/ipv4/tcp_timestamps`
      
      Fixes: 19f6d3f3 ("net/tcp-fastopen: Add new API support")
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Cc: Wei Wang <weiwan@google.com>
      Cc: Yuchung Cheng <ycheng@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      05046af3
    • Yuchung Cheng's avatar
      tcp: avoid setting cwnd to invalid ssthresh after cwnd reduction states · 3914a7ec
      Yuchung Cheng authored
      
      [ Upstream commit ed254971 ]
      
      If the sender switches the congestion control during ECN-triggered
      cwnd-reduction state (CA_CWR), upon exiting recovery cwnd is set to
      the ssthresh value calculated by the previous congestion control. If
      the previous congestion control is BBR that always keep ssthresh
      to TCP_INIFINITE_SSTHRESH, cwnd ends up being infinite. The safe
      step is to avoid assigning invalid ssthresh value when recovery ends.
      Signed-off-by: default avatarYuchung Cheng <ycheng@google.com>
      Signed-off-by: default avatarNeal Cardwell <ncardwell@google.com>
      Acked-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      3914a7ec
    • Guillaume Nault's avatar
      ppp: fix xmit recursion detection on ppp channels · 6ec6ec3b
      Guillaume Nault authored
      
      [ Upstream commit 0a0e1a85 ]
      
      Commit e5dadc65 ("ppp: Fix false xmit recursion detect with two ppp
      devices") dropped the xmit_recursion counter incrementation in
      ppp_channel_push() and relied on ppp_xmit_process() for this task.
      But __ppp_channel_push() can also send packets directly (using the
      .start_xmit() channel callback), in which case the xmit_recursion
      counter isn't incremented anymore. If such packets get routed back to
      the parent ppp unit, ppp_xmit_process() won't notice the recursion and
      will call ppp_channel_push() on the same channel, effectively creating
      the deadlock situation that the xmit_recursion mechanism was supposed
      to prevent.
      
      This patch re-introduces the xmit_recursion counter incrementation in
      ppp_channel_push(). Since the xmit_recursion variable is now part of
      the parent ppp unit, incrementation is skipped if the channel doesn't
      have any. This is fine because only packets routed through the parent
      unit may enter the channel recursively.
      
      Finally, we have to ensure that pch->ppp is not going to be modified
      while executing ppp_channel_push(). Instead of taking this lock only
      while calling ppp_xmit_process(), we now have to hold it for the full
      ppp_channel_push() execution. This respects the ppp locks ordering
      which requires locking ->upl before ->downl.
      
      Fixes: e5dadc65 ("ppp: Fix false xmit recursion detect with two ppp devices")
      Signed-off-by: default avatarGuillaume Nault <g.nault@alphalink.fr>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6ec6ec3b
    • Gao Feng's avatar
      ppp: Fix false xmit recursion detect with two ppp devices · 3b25bfc1
      Gao Feng authored
      
      [ Upstream commit e5dadc65 ]
      
      The global percpu variable ppp_xmit_recursion is used to detect the ppp
      xmit recursion to avoid the deadlock, which is caused by one CPU tries to
      lock the xmit lock twice. But it would report false recursion when one CPU
      wants to send the skb from two different PPP devices, like one L2TP on the
      PPPoE. It is a normal case actually.
      
      Now use one percpu member of struct ppp instead of the gloable variable to
      detect the xmit recursion of one ppp device.
      
      Fixes: 55454a56 ("ppp: avoid dealock on recursive xmit")
      Signed-off-by: default avatarGao Feng <gfree.wind@vip.163.com>
      Signed-off-by: default avatarLiu Jianying <jianying.liu@ikuai8.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      3b25bfc1
  3. 11 Aug, 2017 10 commits