diff --git a/thirdparty/README.md b/thirdparty/README.md
index 42642c09b7..d0e8c05183 100644
--- a/thirdparty/README.md
+++ b/thirdparty/README.md
@@ -209,7 +209,7 @@ Files extracted from upstream source:
 ## zlib
 
 - Upstream: http://www.zlib.net/
-- Version: 1.2.10
+- Version: 1.2.11
 - License: zlib
 
 Files extracted from upstream source:
diff --git a/thirdparty/zlib/deflate.c b/thirdparty/zlib/deflate.c
index 2ad890e354..1ec761448d 100644
--- a/thirdparty/zlib/deflate.c
+++ b/thirdparty/zlib/deflate.c
@@ -52,7 +52,7 @@
 #include "deflate.h"
 
 const char deflate_copyright[] =
-   " deflate 1.2.10 Copyright 1995-2017 Jean-loup Gailly and Mark Adler ";
+   " deflate 1.2.11 Copyright 1995-2017 Jean-loup Gailly and Mark Adler ";
 /*
   If you use the zlib library in a product, an acknowledgment is welcome
   in the documentation of your product. If for some reason you cannot
@@ -586,7 +586,8 @@ int ZEXPORT deflateParams(strm, level, strategy)
     }
     func = configuration_table[s->level].func;
 
-    if ((strategy != s->strategy || func != configuration_table[level].func)) {
+    if ((strategy != s->strategy || func != configuration_table[level].func) &&
+        s->high_water) {
         /* Flush the last buffer: */
         int err = deflate(strm, Z_BLOCK);
         if (err == Z_STREAM_ERROR)
@@ -1671,8 +1672,6 @@ local block_state deflate_stored(s, flush)
             len = left + s->strm->avail_in;     /* limit len to the input */
         if (len > have)
             len = have;                         /* limit len to the output */
-        if (left > len)
-            left = len;                         /* limit window pull to len */
 
         /* If the stored block would be less than min_block in length, or if
          * unable to copy all of the available input when flushing, then try
@@ -1681,13 +1680,13 @@ local block_state deflate_stored(s, flush)
          */
         if (len < min_block && ((len == 0 && flush != Z_FINISH) ||
                                 flush == Z_NO_FLUSH ||
-                                len - left != s->strm->avail_in))
+                                len != left + s->strm->avail_in))
             break;
 
         /* Make a dummy stored block in pending to get the header bytes,
          * including any pending bits. This also updates the debugging counts.
          */
-        last = flush == Z_FINISH && len - left == s->strm->avail_in ? 1 : 0;
+        last = flush == Z_FINISH && len == left + s->strm->avail_in ? 1 : 0;
         _tr_stored_block(s, (char *)0, 0L, last);
 
         /* Replace the lengths in the dummy stored block with len. */
@@ -1699,14 +1698,16 @@ local block_state deflate_stored(s, flush)
         /* Write the stored block header bytes. */
         flush_pending(s->strm);
 
-        /* Update debugging counts for the data about to be copied. */
 #ifdef ZLIB_DEBUG
+        /* Update debugging counts for the data about to be copied. */
         s->compressed_len += len << 3;
         s->bits_sent += len << 3;
 #endif
 
         /* Copy uncompressed bytes from the window to next_out. */
         if (left) {
+            if (left > len)
+                left = len;
             zmemcpy(s->strm->next_out, s->window + s->block_start, left);
             s->strm->next_out += left;
             s->strm->avail_out -= left;
@@ -1756,6 +1757,8 @@ local block_state deflate_stored(s, flush)
         s->block_start = s->strstart;
         s->insert += MIN(used, s->w_size - s->insert);
     }
+    if (s->high_water < s->strstart)
+        s->high_water = s->strstart;
 
     /* If the last block was written to next_out, then done. */
     if (last)
@@ -1783,6 +1786,8 @@ local block_state deflate_stored(s, flush)
         read_buf(s->strm, s->window + s->strstart, have);
         s->strstart += have;
     }
+    if (s->high_water < s->strstart)
+        s->high_water = s->strstart;
 
     /* There was not enough avail_out to write a complete worthy or flushed
      * stored block to next_out. Write a stored block to pending instead, if we
diff --git a/thirdparty/zlib/gzlib.c b/thirdparty/zlib/gzlib.c
index e142ffb3d7..4105e6aff9 100644
--- a/thirdparty/zlib/gzlib.c
+++ b/thirdparty/zlib/gzlib.c
@@ -1,5 +1,5 @@
 /* gzlib.c -- zlib functions common to reading and writing gzip files
- * Copyright (C) 2004, 2010, 2011, 2012, 2013, 2016 Mark Adler
+ * Copyright (C) 2004-2017 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
diff --git a/thirdparty/zlib/gzwrite.c b/thirdparty/zlib/gzwrite.c
index 1ec1da4095..c7b5651d70 100644
--- a/thirdparty/zlib/gzwrite.c
+++ b/thirdparty/zlib/gzwrite.c
@@ -1,5 +1,5 @@
 /* gzwrite.c -- zlib functions for writing gzip files
- * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 Mark Adler
+ * Copyright (C) 2004-2017 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
diff --git a/thirdparty/zlib/inffast.c b/thirdparty/zlib/inffast.c
index 29eb7d8244..0dbd1dbc09 100644
--- a/thirdparty/zlib/inffast.c
+++ b/thirdparty/zlib/inffast.c
@@ -1,5 +1,5 @@
 /* inffast.c -- fast decoding
- * Copyright (C) 1995-2008, 2010, 2013, 2016 Mark Adler
+ * Copyright (C) 1995-2017 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
diff --git a/thirdparty/zlib/inftrees.c b/thirdparty/zlib/inftrees.c
index 8a904ddbce..2ea08fc13e 100644
--- a/thirdparty/zlib/inftrees.c
+++ b/thirdparty/zlib/inftrees.c
@@ -9,7 +9,7 @@
 #define MAXBITS 15
 
 const char inflate_copyright[] =
-   " inflate 1.2.10 Copyright 1995-2017 Mark Adler ";
+   " inflate 1.2.11 Copyright 1995-2017 Mark Adler ";
 /*
   If you use the zlib library in a product, an acknowledgment is welcome
   in the documentation of your product. If for some reason you cannot
@@ -62,7 +62,7 @@ unsigned short FAR *work;
         35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
     static const unsigned short lext[31] = { /* Length codes 257..285 extra */
         16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
-        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 192, 202};
+        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 77, 202};
     static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
         1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
         257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
diff --git a/thirdparty/zlib/trees.c b/thirdparty/zlib/trees.c
index 357f313925..50cf4b4571 100644
--- a/thirdparty/zlib/trees.c
+++ b/thirdparty/zlib/trees.c
@@ -1,5 +1,5 @@
 /* trees.c -- output deflated data using Huffman coding
- * Copyright (C) 1995-2016 Jean-loup Gailly
+ * Copyright (C) 1995-2017 Jean-loup Gailly
  * detect_data_type() function provided freely by Cosmin Truta, 2006
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
@@ -906,7 +906,7 @@ void ZLIB_INTERNAL _tr_align(s)
 
 /* ===========================================================================
  * Determine the best encoding for the current block: dynamic trees, static
- * trees or store, and output the encoded block to the zip file.
+ * trees or store, and write out the encoded block.
  */
 void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
     deflate_state *s;
diff --git a/thirdparty/zlib/zlib.h b/thirdparty/zlib/zlib.h
index dc90dc8d22..f09cdaf1e0 100644
--- a/thirdparty/zlib/zlib.h
+++ b/thirdparty/zlib/zlib.h
@@ -1,5 +1,5 @@
 /* zlib.h -- interface of the 'zlib' general purpose compression library
-  version 1.2.10, January 2nd, 2017
+  version 1.2.11, January 15th, 2017
 
   Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler
 
@@ -37,11 +37,11 @@
 extern "C" {
 #endif
 
-#define ZLIB_VERSION "1.2.10"
-#define ZLIB_VERNUM 0x12a0
+#define ZLIB_VERSION "1.2.11"
+#define ZLIB_VERNUM 0x12b0
 #define ZLIB_VER_MAJOR 1
 #define ZLIB_VER_MINOR 2
-#define ZLIB_VER_REVISION 10
+#define ZLIB_VER_REVISION 11
 #define ZLIB_VER_SUBREVISION 0
 
 /*
@@ -712,10 +712,11 @@ ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
    used to switch between compression and straight copy of the input data, or
    to switch to a different kind of input data requiring a different strategy.
    If the compression approach (which is a function of the level) or the
-   strategy is changed, then the input available so far is compressed with the
-   old level and strategy using deflate(strm, Z_BLOCK).  There are three
-   approaches for the compression levels 0, 1..3, and 4..9 respectively.  The
-   new level and strategy will take effect at the next call of deflate().
+   strategy is changed, and if any input has been consumed in a previous
+   deflate() call, then the input available so far is compressed with the old
+   level and strategy using deflate(strm, Z_BLOCK).  There are three approaches
+   for the compression levels 0, 1..3, and 4..9 respectively.  The new level
+   and strategy will take effect at the next call of deflate().
 
      If a deflate(strm, Z_BLOCK) is performed by deflateParams(), and it does
    not have enough output space to complete, then the parameter change will not
diff --git a/thirdparty/zlib/zutil.c b/thirdparty/zlib/zutil.c
index 56534fba0f..a76c6b0c7e 100644
--- a/thirdparty/zlib/zutil.c
+++ b/thirdparty/zlib/zutil.c
@@ -1,5 +1,5 @@
 /* zutil.c -- target dependent utility functions for the compression library
- * Copyright (C) 1995-2005, 2010, 2011, 2012, 2016 Jean-loup Gailly
+ * Copyright (C) 1995-2017 Jean-loup Gailly
  * For conditions of distribution and use, see copyright notice in zlib.h
  */