1. 23 Oct, 2018 1 commit
    • Eric Dumazet's avatar
      llc: do not use sk_eat_skb() · 604d415e
      Eric Dumazet authored
      syzkaller triggered a use-after-free [1], caused by a combination of
      skb_get() in llc_conn_state_process() and usage of sk_eat_skb()
      
      sk_eat_skb() is assuming the skb about to be freed is only used by
      the current thread. TCP/DCCP stacks enforce this because current
      thread holds the socket lock.
      
      llc_conn_state_process() wants to make sure skb does not disappear,
      and holds a reference on the skb it manipulates. But as soon as this
      skb is added to socket receive queue, another thread can consume it.
      
      This means that llc must use regular skb_unlink() and kfree_skb()
      so that both producer and consumer can safely work on the same skb.
      
      [1]
      BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
      BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:43 [inline]
      BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:967 [inline]
      BUG: KASAN: use-after-free in kfree_skb+0xb7/0x580 net/core/skbuff.c:655
      Read of size 4 at addr ffff8801d1f6fba4 by task ksoftirqd/1/18
      
      CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.19.0-rc8+ #295
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Call Trace:
       __dump_stack lib/dump_stack.c:77 [inline]
       dump_stack+0x1c4/0x2b6 lib/dump_stack.c:113
       print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
       kasan_report_error mm/kasan/report.c:354 [inline]
       kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
       check_memory_region_inline mm/kasan/kasan.c:260 [inline]
       check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
       kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
       atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
       refcount_read include/linux/refcount.h:43 [inline]
       skb_unref include/linux/skbuff.h:967 [inline]
       kfree_skb+0xb7/0x580 net/core/skbuff.c:655
       llc_sap_state_process+0x9b/0x550 net/llc/llc_sap.c:224
       llc_sap_rcv+0x156/0x1f0 net/llc/llc_sap.c:297
       llc_sap_handler+0x65e/0xf80 net/llc/llc_sap.c:438
       llc_rcv+0x79e/0xe20 net/llc/llc_input.c:208
       __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4913
       __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5023
       process_backlog+0x218/0x6f0 net/core/dev.c:5829
       napi_poll net/core/dev.c:6249 [inline]
       net_rx_action+0x7c5/0x1950 net/core/dev.c:6315
       __do_softirq+0x30c/0xb03 kernel/softirq.c:292
       run_ksoftirqd+0x94/0x100 kernel/softirq.c:653
       smpboot_thread_fn+0x68b/0xa00 kernel/smpboot.c:164
       kthread+0x35a/0x420 kernel/kthread.c:246
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
      
      Allocated by task 18:
       save_stack+0x43/0xd0 mm/kasan/kasan.c:448
       set_track mm/kasan/kasan.c:460 [inline]
       kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
       kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
       kmem_cache_alloc_node+0x144/0x730 mm/slab.c:3644
       __alloc_skb+0x119/0x770 net/core/skbuff.c:193
       alloc_skb include/linux/skbuff.h:995 [inline]
       llc_alloc_frame+0xbc/0x370 net/llc/llc_sap.c:54
       llc_station_ac_send_xid_r net/llc/llc_station.c:52 [inline]
       llc_station_rcv+0x1dc/0x1420 net/llc/llc_station.c:111
       llc_rcv+0xc32/0xe20 net/llc/llc_input.c:220
       __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4913
       __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5023
       process_backlog+0x218/0x6f0 net/core/dev.c:5829
       napi_poll net/core/dev.c:6249 [inline]
       net_rx_action+0x7c5/0x1950 net/core/dev.c:6315
       __do_softirq+0x30c/0xb03 kernel/softirq.c:292
      
      Freed by task 16383:
       save_stack+0x43/0xd0 mm/kasan/kasan.c:448
       set_track mm/kasan/kasan.c:460 [inline]
       __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
       kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
       __cache_free mm/slab.c:3498 [inline]
       kmem_cache_free+0x83/0x290 mm/slab.c:3756
       kfree_skbmem+0x154/0x230 net/core/skbuff.c:582
       __kfree_skb+0x1d/0x20 net/core/skbuff.c:642
       sk_eat_skb include/net/sock.h:2366 [inline]
       llc_ui_recvmsg+0xec2/0x1610 net/llc/af_llc.c:882
       sock_recvmsg_nosec net/socket.c:794 [inline]
       sock_recvmsg+0xd0/0x110 net/socket.c:801
       ___sys_recvmsg+0x2b6/0x680 net/socket.c:2278
       __sys_recvmmsg+0x303/0xb90 net/socket.c:2390
       do_sys_recvmmsg+0x181/0x1a0 net/socket.c:2466
       __do_sys_recvmmsg net/socket.c:2484 [inline]
       __se_sys_recvmmsg net/socket.c:2480 [inline]
       __x64_sys_recvmmsg+0xbe/0x150 net/socket.c:2480
       do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      
      The buggy address belongs to the object at ffff8801d1f6fac0
       which belongs to the cache skbuff_head_cache of size 232
      The buggy address is located 228 bytes inside of
       232-byte region [ffff8801d1f6fac0, ffff8801d1f6fba8)
      The buggy address belongs to the page:
      page:ffffea000747dbc0 count:1 mapcount:0 mapping:ffff8801d9be7680 index:0xffff8801d1f6fe80
      flags: 0x2fffc0000000100(slab)
      raw: 02fffc0000000100 ffffea0007346e88 ffffea000705b108 ffff8801d9be7680
      raw: ffff8801d1f6fe80 ffff8801d1f6f0c0 000000010000000b 0000000000000000
      page dumped because: kasan: bad access detected
      
      Memory state around the buggy address:
       ffff8801d1f6fa80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
       ffff8801d1f6fb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
      >ffff8801d1f6fb80: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
                                     ^
       ffff8801d1f6fc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
       ffff8801d1f6fc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
      
      Fixes: 1da177e4 ("Linux-2.6.12-rc2")
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      604d415e
  2. 16 Oct, 2018 1 commit
    • Cong Wang's avatar
      llc: set SOCK_RCU_FREE in llc_sap_add_socket() · 5a8e7aea
      Cong Wang authored
      WHen an llc sock is added into the sk_laddr_hash of an llc_sap,
      it is not marked with SOCK_RCU_FREE.
      
      This causes that the sock could be freed while it is still being
      read by __llc_lookup_established() with RCU read lock. sock is
      refcounted, but with RCU read lock, nothing prevents the readers
      getting a zero refcnt.
      
      Fix it by setting SOCK_RCU_FREE in llc_sap_add_socket().
      
      Reported-by: syzbot+11e05f04c15e03be5254@syzkaller.appspotmail.com
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      5a8e7aea
  3. 13 Sep, 2018 1 commit
  4. 07 Aug, 2018 1 commit
  5. 24 Jul, 2018 1 commit
  6. 28 Jun, 2018 1 commit
    • Linus Torvalds's avatar
      Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL · a11e1d43
      Linus Torvalds authored
      The poll() changes were not well thought out, and completely
      unexplained.  They also caused a huge performance regression, because
      "->poll()" was no longer a trivial file operation that just called down
      to the underlying file operations, but instead did at least two indirect
      calls.
      
      Indirect calls are sadly slow now with the Spectre mitigation, but the
      performance problem could at least be largely mitigated by changing the
      "->get_poll_head()" operation to just have a per-file-descriptor pointer
      to the poll head instead.  That gets rid of one of the new indirections.
      
      But that doesn't fix the new complexity that is completely unwarranted
      for the regular case.  The (undocumented) reason for the poll() changes
      was some alleged AIO poll race fixing, but we don't make the common case
      slower and more complex for some uncommon special case, so this all
      really needs way more explanations and most likely a fundamental
      redesign.
      
      [ This revert is a revert of about 30 different commits, not reverted
        individually because that would just be unnecessarily messy  - Linus ]
      
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Christoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a11e1d43
  7. 26 May, 2018 1 commit
  8. 16 May, 2018 1 commit
  9. 08 May, 2018 1 commit
    • Eric Dumazet's avatar
      llc: better deal with too small mtu · 2c5d5b13
      Eric Dumazet authored
      syzbot loves to set very small mtu on devices, since it brings joy.
      We must make llc_ui_sendmsg() fool proof.
      
      usercopy: Kernel memory overwrite attempt detected to wrapped address (offset 0, size 18446612139802320068)!
      
      kernel BUG at mm/usercopy.c:100!
      invalid opcode: 0000 [#1] SMP KASAN
      Dumping ftrace buffer:
         (ftrace buffer empty)
      Modules linked in:
      CPU: 0 PID: 17464 Comm: syz-executor1 Not tainted 4.17.0-rc3+ #36
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      RIP: 0010:usercopy_abort+0xbb/0xbd mm/usercopy.c:88
      RSP: 0018:ffff8801868bf800 EFLAGS: 00010282
      RAX: 000000000000006c RBX: ffffffff87d2fb00 RCX: 0000000000000000
      RDX: 000000000000006c RSI: ffffffff81610731 RDI: ffffed0030d17ef6
      RBP: ffff8801868bf858 R08: ffff88018daa4200 R09: ffffed003b5c4fb0
      R10: ffffed003b5c4fb0 R11: ffff8801dae27d87 R12: ffffffff87d2f8e0
      R13: ffffffff87d2f7a0 R14: ffffffff87d2f7a0 R15: ffffffff87d2f7a0
      FS:  00007f56a14ac700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 0000001b2bc21000 CR3: 00000001abeb1000 CR4: 00000000001426f0
      DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000030602
      Call Trace:
       check_bogus_address mm/usercopy.c:153 [inline]
       __check_object_size+0x5d9/0x5d9 mm/usercopy.c:256
       check_object_size include/linux/thread_info.h:108 [inline]
       check_copy_size include/linux/thread_info.h:139 [inline]
       copy_from_iter_full include/linux/uio.h:121 [inline]
       memcpy_from_msg include/linux/skbuff.h:3305 [inline]
       llc_ui_sendmsg+0x4b1/0x1530 net/llc/af_llc.c:941
       sock_sendmsg_nosec net/socket.c:629 [inline]
       sock_sendmsg+0xd5/0x120 net/socket.c:639
       __sys_sendto+0x3d7/0x670 net/socket.c:1789
       __do_sys_sendto net/socket.c:1801 [inline]
       __se_sys_sendto net/socket.c:1797 [inline]
       __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797
       do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      RIP: 0033:0x455979
      RSP: 002b:00007f56a14abc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
      RAX: ffffffffffffffda RBX: 00007f56a14ac6d4 RCX: 0000000000455979
      RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000018
      RBP: 000000000072bea0 R08: 00000000200012c0 R09: 0000000000000010
      R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
      R13: 0000000000000548 R14: 00000000006fbf60 R15: 0000000000000000
      Code: 55 c0 e8 c0 55 bb ff ff 75 c8 48 8b 55 c0 4d 89 f9 ff 75 d0 4d 89 e8 48 89 d9 4c 89 e6 41 56 48 c7 c7 80 fa d2 87 e8 a0 0b a3 ff <0f> 0b e8 95 55 bb ff e8 c0 a8 f7 ff 8b 95 14 ff ff ff 4d 89 e8
      RIP: usercopy_abort+0xbb/0xbd mm/usercopy.c:88 RSP: ffff8801868bf800
      
      Fixes: 1da177e4 ("Linux-2.6.12-rc2")
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2c5d5b13
  10. 22 Apr, 2018 2 commits
  11. 19 Apr, 2018 1 commit
    • Cong Wang's avatar
      llc: hold llc_sap before release_sock() · f7e43672
      Cong Wang authored
      syzbot reported we still access llc->sap in llc_backlog_rcv()
      after it is freed in llc_sap_remove_socket():
      
      Call Trace:
       __dump_stack lib/dump_stack.c:77 [inline]
       dump_stack+0x1b9/0x294 lib/dump_stack.c:113
       print_address_description+0x6c/0x20b mm/kasan/report.c:256
       kasan_report_error mm/kasan/report.c:354 [inline]
       kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
       __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
       llc_conn_ac_send_sabme_cmd_p_set_x+0x3a8/0x460 net/llc/llc_c_ac.c:785
       llc_exec_conn_trans_actions net/llc/llc_conn.c:475 [inline]
       llc_conn_service net/llc/llc_conn.c:400 [inline]
       llc_conn_state_process+0x4e1/0x13a0 net/llc/llc_conn.c:75
       llc_backlog_rcv+0x195/0x1e0 net/llc/llc_conn.c:891
       sk_backlog_rcv include/net/sock.h:909 [inline]
       __release_sock+0x12f/0x3a0 net/core/sock.c:2335
       release_sock+0xa4/0x2b0 net/core/sock.c:2850
       llc_ui_release+0xc8/0x220 net/llc/af_llc.c:204
      
      llc->sap is refcount'ed and llc_sap_remove_socket() is paired
      with llc_sap_add_socket(). This can be amended by holding its refcount
      before llc_sap_remove_socket() and releasing it after release_sock().
      
      Reported-by: <syzbot+6e181fc95081c2cf9051@syzkaller.appspotmail.com>
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f7e43672
  12. 27 Mar, 2018 1 commit
  13. 26 Mar, 2018 1 commit
  14. 12 Mar, 2018 1 commit
  15. 12 Feb, 2018 1 commit
    • Denys Vlasenko's avatar
      net: make getname() functions return length rather than use int* parameter · 9b2c45d4
      Denys Vlasenko authored
      Changes since v1:
      Added changes in these files:
          drivers/infiniband/hw/usnic/usnic_transport.c
          drivers/staging/lustre/lnet/lnet/lib-socket.c
          drivers/target/iscsi/iscsi_target_login.c
          drivers/vhost/net.c
          fs/dlm/lowcomms.c
          fs/ocfs2/cluster/tcp.c
          security/tomoyo/network.c
      
      Before:
      All these functions either return a negative error indicator,
      or store length of sockaddr into "int *socklen" parameter
      and return zero on success.
      
      "int *socklen" parameter is awkward. For example, if caller does not
      care, it still needs to provide on-stack storage for the value
      it does not need.
      
      None of the many FOO_getname() functions of various protocols
      ever used old value of *socklen. They always just overwrite it.
      
      This change drops this parameter, and makes all these functions, on success,
      return length of sockaddr. It's always >= 0 and can be differentiated
      from an error.
      
      Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.
      
      rpc_sockname() lost "int buflen" parameter, since its only use was
      to be passed to kernel_getsockname() as &buflen and subsequently
      not used in any way.
      
      Userspace API is not changed.
      
          text    data     bss      dec     hex filename
      30108430 2633624  873672 33615726 200ef6e vmlinux.before.o
      30108109 2633612  873672 33615393 200ee21 vmlinux.o
      Signed-off-by: default avatarDenys Vlasenko <dvlasenk@redhat.com>
      CC: David S. Miller <davem@davemloft.net>
      CC: linux-kernel@vger.kernel.org
      CC: netdev@vger.kernel.org
      CC: linux-bluetooth@vger.kernel.org
      CC: linux-decnet-user@lists.sourceforge.net
      CC: linux-wireless@vger.kernel.org
      CC: linux-rdma@vger.kernel.org
      CC: linux-sctp@vger.kernel.org
      CC: linux-nfs@vger.kernel.org
      CC: linux-x25@vger.kernel.org
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9b2c45d4
  16. 16 Jan, 2018 1 commit
    • Alexey Dobriyan's avatar
      net: delete /proc THIS_MODULE references · 96890d62
      Alexey Dobriyan authored
      /proc has been ignoring struct file_operations::owner field for 10 years.
      Specifically, it started with commit 786d7e16
      ("Fix rmmod/read/write races in /proc entries"). Notice the chunk where
      inode->i_fop is initialized with proxy struct file_operations for
      regular files:
      
      	-               if (de->proc_fops)
      	-                       inode->i_fop = de->proc_fops;
      	+               if (de->proc_fops) {
      	+                       if (S_ISREG(inode->i_mode))
      	+                               inode->i_fop = &proc_reg_file_ops;
      	+                       else
      	+                               inode->i_fop = de->proc_fops;
      	+               }
      
      VFS stopped pinning module at this point.
      Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      96890d62
  17. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  18. 25 Oct, 2017 2 commits
    • Mark Rutland's avatar
      locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns... · 6aa7de05
      Mark Rutland authored
      locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()
      
      Please do not apply this to mainline directly, instead please re-run the
      coccinelle script shown below and apply its output.
      
      For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
      preference to ACCESS_ONCE(), and new code is expected to use one of the
      former. So far, there's been no reason to change most existing uses of
      ACCESS_ONCE(), as these aren't harmful, and changing them results in
      churn.
      
      However, for some features, the read/write distinction is critical to
      correct operation. To distinguish these cases, separate read/write
      accessors must be used. This patch migrates (most) remaining
      ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
      coccinelle script:
      
      ----
      // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
      // WRITE_ONCE()
      
      // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
      
      virtual patch
      
      @ depends on patch @
      expression E1, E2;
      @@
      
      - ACCESS_ONCE(E1) = E2
      + WRITE_ONCE(E1, E2)
      
      @ depends on patch @
      expression E;
      @@
      
      - ACCESS_ONCE(E)
      + READ_ONCE(E)
      ----
      Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: davem@davemloft.net
      Cc: linux-arch@vger.kernel.org
      Cc: mpe@ellerman.id.au
      Cc: shuah@kernel.org
      Cc: snitzer@redhat.com
      Cc: thor.thayer@linux.intel.com
      Cc: tj@kernel.org
      Cc: viro@zeniv.linux.org.uk
      Cc: will.deacon@arm.com
      Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      6aa7de05
    • Kees Cook's avatar
      net: LLC: Convert timers to use timer_setup() · fc8bcaa0
      Kees Cook authored
      In preparation for unconditionally passing the struct timer_list pointer to
      all timer callbacks, switch to using the new timer_setup() and from_timer()
      to pass the timer pointer explicitly.
      
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Eric Dumazet <edumazet@google.com>
      Cc: Hans Liljestrand <ishkamiel@gmail.com>
      Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
      Cc: "Reshetova, Elena" <elena.reshetova@intel.com>
      Cc: netdev@vger.kernel.org
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      fc8bcaa0
  19. 04 Jul, 2017 1 commit
  20. 01 Jul, 2017 1 commit
  21. 26 May, 2017 1 commit
    • linzhang's avatar
      net: llc: add lock_sock in llc_ui_bind to avoid a race condition · 0908cf4d
      linzhang authored
      There is a race condition in llc_ui_bind if two or more processes/threads
      try to bind a same socket.
      
      If more processes/threads bind a same socket success that will lead to
      two problems, one is this action is not what we expected, another is
      will lead to kernel in unstable status or oops(in my simple test case,
      cause llc2.ko can't unload).
      
      The current code is test SOCK_ZAPPED bit to avoid a process to
      bind a same socket twice but that is can't avoid more processes/threads
      try to bind a same socket at the same time.
      
      So, add lock_sock in llc_ui_bind like others, such as llc_ui_connect.
      Signed-off-by: default avatarLin Zhang <xiaolou4617@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0908cf4d
  22. 18 Apr, 2017 1 commit
    • Paul E. McKenney's avatar
      mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU · 5f0d5a3a
      Paul E. McKenney authored
      A group of Linux kernel hackers reported chasing a bug that resulted
      from their assumption that SLAB_DESTROY_BY_RCU provided an existence
      guarantee, that is, that no block from such a slab would be reallocated
      during an RCU read-side critical section.  Of course, that is not the
      case.  Instead, SLAB_DESTROY_BY_RCU only prevents freeing of an entire
      slab of blocks.
      
      However, there is a phrase for this, namely "type safety".  This commit
      therefore renames SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU in order
      to avoid future instances of this sort of confusion.
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: <linux-mm@kvack.org>
      Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
      Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
      [ paulmck: Add comments mentioning the old name, as requested by Eric
        Dumazet, in order to help people familiar with the old name find
        the new one. ]
      Acked-by: default avatarDavid Rientjes <rientjes@google.com>
      5f0d5a3a
  23. 10 Mar, 2017 1 commit
    • David Howells's avatar
      net: Work around lockdep limitation in sockets that use sockets · cdfbabfb
      David Howells authored
      Lockdep issues a circular dependency warning when AFS issues an operation
      through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.
      
      The theory lockdep comes up with is as follows:
      
       (1) If the pagefault handler decides it needs to read pages from AFS, it
           calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
           creating a call requires the socket lock:
      
      	mmap_sem must be taken before sk_lock-AF_RXRPC
      
       (2) afs_open_socket() opens an AF_RXRPC socket and binds it.  rxrpc_bind()
           binds the underlying UDP socket whilst holding its socket lock.
           inet_bind() takes its own socket lock:
      
      	sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET
      
       (3) Reading from a TCP socket into a userspace buffer might cause a fault
           and thus cause the kernel to take the mmap_sem, but the TCP socket is
           locked whilst doing this:
      
      	sk_lock-AF_INET must be taken before mmap_sem
      
      However, lockdep's theory is wrong in this instance because it deals only
      with lock classes and not individual locks.  The AF_INET lock in (2) isn't
      really equivalent to the AF_INET lock in (3) as the former deals with a
      socket entirely internal to the kernel that never sees userspace.  This is
      a limitation in the design of lockdep.
      
      Fix the general case by:
      
       (1) Double up all the locking keys used in sockets so that one set are
           used if the socket is created by userspace and the other set is used
           if the socket is created by the kernel.
      
       (2) Store the kern parameter passed to sk_alloc() in a variable in the
           sock struct (sk_kern_sock).  This informs sock_lock_init(),
           sock_init_data() and sk_clone_lock() as to the lock keys to be used.
      
           Note that the child created by sk_clone_lock() inherits the parent's
           kern setting.
      
       (3) Add a 'kern' parameter to ->accept() that is analogous to the one
           passed in to ->create() that distinguishes whether kernel_accept() or
           sys_accept4() was the caller and can be passed to sk_alloc().
      
           Note that a lot of accept functions merely dequeue an already
           allocated socket.  I haven't touched these as the new socket already
           exists before we get the parameter.
      
           Note also that there are a couple of places where I've made the accepted
           socket unconditionally kernel-based:
      
      	irda_accept()
      	rds_rcp_accept_one()
      	tcp_accept_from_sock()
      
           because they follow a sock_create_kern() and accept off of that.
      
      Whilst creating this, I noticed that lustre and ocfs don't create sockets
      through sock_create_kern() and thus they aren't marked as for-kernel,
      though they appear to be internal.  I wonder if these should do that so
      that they use the new set of lock keys.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      cdfbabfb
  24. 02 Mar, 2017 1 commit
  25. 13 Feb, 2017 1 commit
  26. 14 Nov, 2016 1 commit
  27. 17 Sep, 2016 1 commit
  28. 04 May, 2016 1 commit
  29. 14 Apr, 2016 1 commit
  30. 17 Feb, 2016 1 commit
  31. 27 Jul, 2015 1 commit
  32. 11 May, 2015 1 commit
  33. 02 Mar, 2015 1 commit
  34. 25 Jan, 2015 1 commit
  35. 10 Dec, 2014 3 commits
  36. 24 Nov, 2014 1 commit