1. 19 5月, 2018 1 次提交
  2. 18 5月, 2018 1 次提交
    • W
      proc: do not access cmdline nor environ from file-backed areas · 7f7ccc2c
      Willy Tarreau 提交于
      proc_pid_cmdline_read() and environ_read() directly access the target
      process' VM to retrieve the command line and environment. If this
      process remaps these areas onto a file via mmap(), the requesting
      process may experience various issues such as extra delays if the
      underlying device is slow to respond.
      
      Let's simply refuse to access file-backed areas in these functions.
      For this we add a new FOLL_ANON gup flag that is passed to all calls
      to access_remote_vm(). The code already takes care of such failures
      (including unmapped areas). Accesses via /proc/pid/mem were not
      changed though.
      
      This was assigned CVE-2018-1120.
      
      Note for stable backports: the patch may apply to kernels prior to 4.11
      but silently miss one location; it must be checked that no call to
      access_remote_vm() keeps zero as the last argument.
      Reported-by: NQualys Security Advisory <qsa@qualys.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NWilly Tarreau <w@1wt.eu>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7f7ccc2c
  3. 14 5月, 2018 14 次提交
    • D
      afs: Fix the non-encryption of calls · 4776cab4
      David Howells 提交于
      Some AFS servers refuse to accept unencrypted traffic, so can't be accessed
      with kAFS.  Set the AF_RXRPC security level to encrypt client calls to deal
      with this.
      
      Note that incoming service calls are set by the remote client and so aren't
      affected by this.
      
      This requires an AF_RXRPC patch to pass the value set by setsockopt to calls
      begun by the kernel.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      4776cab4
    • D
      afs: Fix CB.CallBack handling · 428edade
      David Howells 提交于
      The handling of CB.CallBack messages sent by the fileserver to the client
      is broken in that they are currently being processed after the reply has
      been transmitted.
      
      This is not what the fileserver expects, however.  It holds up change
      visibility until the reply comes so as to maintain cache coherency, and so
      expects the client to have to refetch the state on the affected files.
      
      Fix CB.CallBack handling to perform the callback break before sending the
      reply.
      
      The fileserver is free to hold up status fetches issued by other threads on
      the same client that occur in reponse to the callback until any pending
      changes have been committed.
      
      Fixes: d001648e ("rxrpc: Don't expose skbs to in-kernel users [ver #2]")
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      428edade
    • D
      afs: Fix whole-volume callback handling · 68251f0a
      David Howells 提交于
      It's possible for an AFS file server to issue a whole-volume notification
      that callbacks on all the vnodes in the file have been broken.  This is
      done for R/O and backup volumes (which don't have per-file callbacks) and
      for things like a volume being taken offline.
      
      Fix callback handling to detect whole-volume notifications, to track it
      across operations and to check it during inode validation.
      
      Fixes: c435ee34 ("afs: Overhaul the callback handling")
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      68251f0a
    • M
      afs: Fix afs_find_server search loop · f9c1bba3
      Marc Dionne 提交于
      The code that looks up servers by addresses makes the assumption
      that the list of addresses for a server is sorted.  It exits the
      loop if it finds that the target address is larger than the
      current candidate.  As the list is not currently sorted, this
      can lead to a failure to find a matching server, which can cause
      callbacks from that server to be ignored.
      
      Remove the early exit case so that the complete list is searched.
      
      Fixes: d2ddc776 ("afs: Overhaul volume and server record caching and fileserver rotation")
      Signed-off-by: NMarc Dionne <marc.dionne@auristor.com>
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      f9c1bba3
    • D
      afs: Fix the handling of an unfound server in CM operations · a86b06d1
      David Howells 提交于
      If the client cache manager operations that need the server record
      (CB.Callback, CB.InitCallBackState, and CB.InitCallBackState3) can't find
      the server record, they abort the call from the file server with
      RX_CALL_DEAD when they should return okay.
      
      Fixes: c35eccb1 ("[AFS]: Implement the CB.InitCallBackState3 operation.")
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      a86b06d1
    • D
      afs: Add a tracepoint to record callbacks from unlisted servers · 3709a399
      David Howells 提交于
      Add a tracepoint to record callbacks from servers for which we don't have a
      record.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      3709a399
    • D
      afs: Fix the handling of CB.InitCallBackState3 to find the server by UUID · 001ab5a6
      David Howells 提交于
      Fix the handling of the CB.InitCallBackState3 service call to find the
      record of a server that we're using by looking it up by the UUID passed as
      the parameter rather than by its address (of which it might have many, and
      which may change).
      
      Fixes: c35eccb1 ("[AFS]: Implement the CB.InitCallBackState3 operation.")
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      001ab5a6
    • D
      afs: Fix VNOVOL handling in address rotation · 3d9fa911
      David Howells 提交于
      If a volume location record lists multiple file servers for a volume, then
      it's possible that due to a misconfiguration or a changing configuration
      that one of the file servers doesn't know about it yet and will abort
      VNOVOL.  Currently, the rotation algorithm will stop with EREMOTEIO.
      
      Fix this by moving on to try the next server if VNOVOL is returned.  Once
      all the servers have been tried and the record rechecked, the algorithm
      will stop with EREMOTEIO or ENOMEDIUM.
      
      Fixes: d2ddc776 ("afs: Overhaul volume and server record caching and fileserver rotation")
      Reported-by: NMarc Dionne <marc.dionne@auristor.com>
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      3d9fa911
    • D
      afs: Fix AFSFetchStatus decoder to provide OpenAFS compatibility · 684b0f68
      David Howells 提交于
      The OpenAFS server's RXAFS_InlineBulkStatus implementation has a bug
      whereby if an error occurs on one of the vnodes being queried, then the
      errorCode field is set correctly in the corresponding status, but the
      interfaceVersion field is left unset.
      
      Fix kAFS to deal with this by evaluating the AFSFetchStatus blob against
      the following cases when called from FS.InlineBulkStatus delivery:
      
       (1) If InterfaceVersion == 0 then:
      
           (a) If errorCode != 0 then it indicates the abort code for the
               corresponding vnode.
      
           (b) If errorCode == 0 then the status record is invalid.
      
       (2) If InterfaceVersion == 1 then:
      
           (a) If errorCode != 0 then it indicates the abort code for the
               corresponding vnode.
      
           (b) If errorCode == 0 then the status record is valid and can be
           	 parsed.
      
       (3) If InterfaceVersion is anything else then the status record is
           invalid.
      
      Fixes: dd9fbcb8 ("afs: Rearrange status mapping")
      Reported-by: NJeffrey Altman <jaltman@auristor.com>
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      684b0f68
    • D
      afs: Fix server rotation's handling of fileserver probe failure · ec5a3b4b
      David Howells 提交于
      The server rotation algorithm just gives up if it fails to probe a
      fileserver.  Fix this by rotating to the next fileserver instead.
      
      Fixes: d2ddc776 ("afs: Overhaul volume and server record caching and fileserver rotation")
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      ec5a3b4b
    • D
      afs: Fix refcounting in callback registration · d4a96bec
      David Howells 提交于
      The refcounting on afs_cb_interest struct objects in
      afs_register_server_cb_interest() is wrong as it uses the server list
      entry's call back interest pointer without regard for the fact that it
      might be replaced at any time and the object thrown away.
      
      Fix this by:
      
       (1) Put a lock on the afs_server_list struct that can be used to
           mediate access to the callback interest pointers in the servers array.
      
       (2) Keep a ref on the callback interest that we get from the entry.
      
       (3) Dropping the old reference held by vnode->cb_interest if we replace
           the pointer.
      
      Fixes: c435ee34 ("afs: Overhaul the callback handling")
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      d4a96bec
    • D
      afs: Fix giving up callbacks on server destruction · f2686b09
      David Howells 提交于
      When a server record is destroyed, we want to send a message to the server
      telling it that we're giving up all the callbacks it has promised us.
      
      Apply two fixes to this:
      
       (1) Only send the FS.GiveUpAllCallBacks message if we actually got a
           callback from that server.  We assume this to be the case if we
           performed at least one successful FS operation on that server.
      
       (2) Send it to the address last used for that server rather than always
           picking the first address in the list (which might be unreachable).
      
      Fixes: d2ddc776 ("afs: Overhaul volume and server record caching and fileserver rotation")
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      f2686b09
    • D
      afs: Fix address list parsing · 01fd79e6
      David Howells 提交于
      The parsing of port specifiers in the address list obtained from the DNS
      resolution upcall doesn't work as in4_pton() and in6_pton() will fail on
      encountering an unexpected delimiter (in this case, the '+' marking the
      port number).  However, in*_pton() can't be given multiple specifiers.
      
      Fix this by finding the delimiter in advance and not relying on in*_pton()
      to find the end of the address for us.
      
      Fixes: 8b2a464c ("afs: Add an address list concept")
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      01fd79e6
    • D
      afs: Fix directory page locking · b61f7dcf
      David Howells 提交于
      The afs directory loading code (primarily afs_read_dir()) locks all the
      pages that hold a directory's content blob to defend against
      getdents/getdents races and getdents/lookup races where the competitors
      issue conflicting reads on the same data.  As the reads will complete
      consecutively, they may retrieve different versions of the data and
      one may overwrite the data that the other is busy parsing.
      
      Fix this by not locking the pages at all, but rather by turning the
      validation lock into an rwsem and getting an exclusive lock on it whilst
      reading the data or validating the attributes and a shared lock whilst
      parsing the data.  Sharing the attribute validation lock should be fine as
      the data fetch will retrieve the attributes also.
      
      The individual page locks aren't needed at all as the only place they're
      being used is to serialise data loading.
      
      Without this patch, the:
      
       	if (!test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
      		...
      	}
      
      part of afs_read_dir() may be skipped, leaving the pages unlocked when we
      hit the success: clause - in which case we try to unlock the not-locked
      pages, leading to the following oops:
      
        page:ffffe38b405b4300 count:3 mapcount:0 mapping:ffff98156c83a978 index:0x0
        flags: 0xfffe000001004(referenced|private)
        raw: 000fffe000001004 ffff98156c83a978 0000000000000000 00000003ffffffff
        raw: dead000000000100 dead000000000200 0000000000000001 ffff98156b27c000
        page dumped because: VM_BUG_ON_PAGE(!PageLocked(page))
        page->mem_cgroup:ffff98156b27c000
        ------------[ cut here ]------------
        kernel BUG at mm/filemap.c:1205!
        ...
        RIP: 0010:unlock_page+0x43/0x50
        ...
        Call Trace:
         afs_dir_iterate+0x789/0x8f0 [kafs]
         ? _cond_resched+0x15/0x30
         ? kmem_cache_alloc_trace+0x166/0x1d0
         ? afs_do_lookup+0x69/0x490 [kafs]
         ? afs_do_lookup+0x101/0x490 [kafs]
         ? key_default_cmp+0x20/0x20
         ? request_key+0x3c/0x80
         ? afs_lookup+0xf1/0x340 [kafs]
         ? __lookup_slow+0x97/0x150
         ? lookup_slow+0x35/0x50
         ? walk_component+0x1bf/0x490
         ? path_lookupat.isra.52+0x75/0x200
         ? filename_lookup.part.66+0xa0/0x170
         ? afs_end_vnode_operation+0x41/0x60 [kafs]
         ? __check_object_size+0x9c/0x171
         ? strncpy_from_user+0x4a/0x170
         ? vfs_statx+0x73/0xe0
         ? __do_sys_newlstat+0x39/0x70
         ? __x64_sys_getdents+0xc9/0x140
         ? __x64_sys_getdents+0x140/0x140
         ? do_syscall_64+0x5b/0x160
         ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
      
      Fixes: f3ddee8d ("afs: Fix directory handling")
      Reported-by: NMarc Dionne <marc.dionne@auristor.com>
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      b61f7dcf
  4. 12 5月, 2018 2 次提交
  5. 11 5月, 2018 1 次提交
  6. 10 5月, 2018 5 次提交
  7. 04 5月, 2018 1 次提交
    • J
      bdi: Fix oops in wb_workfn() · b8b78495
      Jan Kara 提交于
      Syzbot has reported that it can hit a NULL pointer dereference in
      wb_workfn() due to wb->bdi->dev being NULL. This indicates that
      wb_workfn() was called for an already unregistered bdi which should not
      happen as wb_shutdown() called from bdi_unregister() should make sure
      all pending writeback works are completed before bdi is unregistered.
      Except that wb_workfn() itself can requeue the work with:
      
      	mod_delayed_work(bdi_wq, &wb->dwork, 0);
      
      and if this happens while wb_shutdown() is waiting in:
      
      	flush_delayed_work(&wb->dwork);
      
      the dwork can get executed after wb_shutdown() has finished and
      bdi_unregister() has cleared wb->bdi->dev.
      
      Make wb_workfn() use wakeup_wb() for requeueing the work which takes all
      the necessary precautions against racing with bdi unregistration.
      
      CC: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      CC: Tejun Heo <tj@kernel.org>
      Fixes: 839a8e86Reported-by: Nsyzbot <syzbot+9873874c735f2892e7e9@syzkaller.appspotmail.com>
      Reviewed-by: NDave Chinner <dchinner@redhat.com>
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      b8b78495
  8. 03 5月, 2018 1 次提交
  9. 02 5月, 2018 2 次提交
    • F
      Btrfs: send, fix missing truncate for inode with prealloc extent past eof · a6aa10c7
      Filipe Manana 提交于
      An incremental send operation can miss a truncate operation when an inode
      has an increased size in the send snapshot and a prealloc extent beyond
      its size.
      
      Consider the following scenario where a necessary truncate operation is
      missing in the incremental send stream:
      
      1) In the parent snapshot an inode has a size of 1282957 bytes and it has
         no prealloc extents beyond its size;
      
      2) In the the send snapshot it has a size of 5738496 bytes and has a new
         extent at offsets 1884160 (length of 106496 bytes) and a prealloc
         extent beyond eof at offset 6729728 (and a length of 339968 bytes);
      
      3) When processing the prealloc extent, at offset 6729728, we end up at
         send.c:send_write_or_clone() and set the @len variable to a value of
         18446744073708560384 because @offset plus the original @len value is
         larger then the inode's size (6729728 + 339968 > 5738496). We then
         call send_extent_data(), with that @offset and @len, which in turn
         calls send_write(), and then the later calls fill_read_buf(). Because
         the offset passed to fill_read_buf() is greater then inode's i_size,
         this function returns 0 immediately, which makes send_write() and
         send_extent_data() do nothing and return immediately as well. When
         we get back to send.c:send_write_or_clone() we adjust the value
         of sctx->cur_inode_next_write_offset to @offset plus @len, which
         corresponds to 6729728 + 18446744073708560384 = 5738496, which is
         precisely the the size of the inode in the send snapshot;
      
      4) Later when at send.c:finish_inode_if_needed() we determine that
         we don't need to issue a truncate operation because the value of
         sctx->cur_inode_next_write_offset corresponds to the inode's new
         size, 5738496 bytes. This is wrong because the last write operation
         that was issued started at offset 1884160 with a length of 106496
         bytes, so the correct value for sctx->cur_inode_next_write_offset
         should be 1990656 (1884160 + 106496), so that a truncate operation
         with a value of 5738496 bytes would have been sent to insert a
         trailing hole at the destination.
      
      So fix the issue by making send.c:send_write_or_clone() not attempt
      to send write or clone operations for extents that start beyond the
      inode's size, since such attempts do nothing but waste time by
      calling helper functions and allocating path structures, and send
      currently has no fallocate command in order to create prealloc extents
      at the destination (either beyond a file's eof or not).
      
      The issue was found running the test btrfs/007 from fstests using a seed
      value of 1524346151 for fsstress.
      Reported-by: NGu, Jinxiang <gujx@cn.fujitsu.com>
      Fixes: ffa7c429 ("Btrfs: send, do not issue unnecessary truncate operations")
      Signed-off-by: NFilipe Manana <fdmanana@suse.com>
      Signed-off-by: NDavid Sterba <dsterba@suse.com>
      a6aa10c7
    • E
      btrfs: Take trans lock before access running trans in check_delayed_ref · 998ac6d2
      ethanwu 提交于
      In preivous patch:
      Btrfs: kill trans in run_delalloc_nocow and btrfs_cross_ref_exist
      We avoid starting btrfs transaction and get this information from
      fs_info->running_transaction directly.
      
      When accessing running_transaction in check_delayed_ref, there's a
      chance that current transaction will be freed by commit transaction
      after the NULL pointer check of running_transaction is passed.
      
      After looking all the other places using fs_info->running_transaction,
      they are either protected by trans_lock or holding the transactions.
      
      Fix this by using trans_lock and increasing the use_count.
      
      Fixes: e4c3b2dc ("Btrfs: kill trans in run_delalloc_nocow and btrfs_cross_ref_exist")
      CC: stable@vger.kernel.org # 4.14+
      Signed-off-by: Nethanwu <ethanwu@synology.com>
      Signed-off-by: NDavid Sterba <dsterba@suse.com>
      998ac6d2
  10. 27 4月, 2018 1 次提交
  11. 26 4月, 2018 5 次提交
  12. 24 4月, 2018 3 次提交
  13. 23 4月, 2018 1 次提交
  14. 21 4月, 2018 2 次提交