Rémi Bernon : crypt32: Grow item size buffer by more than 1 at a time.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 8b8b43d5f3ebff602bbd15d939de7766ef252114
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=8b8b43d5f3ebff602bbd15d93...

Author: Rémi Bernon <rbernon(a)codeweavers.com>
Date:   Fri Jul  2 12:18:22 2021 +0200

crypt32: Grow item size buffer by more than 1 at a time.

When Steam starts and connects, it sometimes does some crypt32
processing and ends up spending a huge amount of time in ntdll memcpy,
reallocating buffers, effectively getting stuck while connecting to the
user account.

Signed-off-by: Rémi Bernon <rbernon(a)codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard(a)winehq.org>

---

 dlls/crypt32/decode.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/dlls/crypt32/decode.c b/dlls/crypt32/decode.c
index 5d195d42f7b..a0e78d62b4d 100644
--- a/dlls/crypt32/decode.c
+++ b/dlls/crypt32/decode.c
@@ -628,7 +628,7 @@ static BOOL CRYPT_AsnDecodeArray(const struct AsnArrayDescriptor *arrayDesc,
 
         if ((ret = CRYPT_GetLengthIndefinite(pbEncoded, cbEncoded, &dataLen)))
         {
-            DWORD bytesNeeded = arrayDesc->minArraySize, cItems = 0, decoded;
+            DWORD bytesNeeded = arrayDesc->minArraySize, cItems = 0, capacity = 0, decoded;
             BYTE lenBytes = GET_LEN_BYTES(pbEncoded[1]);
             /* There can be arbitrarily many items, but there is often only one.
              */
@@ -687,17 +687,18 @@ static BOOL CRYPT_AsnDecodeArray(const struct AsnArrayDescriptor *arrayDesc,
                                 continue;
                             }
 
-                            cItems++;
-                            if (itemSizes != &itemSize)
-                                itemSizes = CryptMemRealloc(itemSizes,
-                                 cItems * sizeof(struct AsnArrayItemSize));
-                            else if (cItems > 1)
+                            if (++cItems <= 1)
+                                itemSizes = &itemSize;
+                            else if (itemSizes == &itemSize)
                             {
-                                itemSizes =
-                                 CryptMemAlloc(
-                                 cItems * sizeof(struct AsnArrayItemSize));
-                                if (itemSizes)
-                                    *itemSizes = itemSize;
+                                capacity = 1024;
+                                itemSizes = CryptMemAlloc(capacity * sizeof(struct AsnArrayItemSize));
+                                if (itemSizes) *itemSizes = itemSize;
+                            }
+                            else if (cItems > capacity)
+                            {
+                                capacity = capacity * 3 / 2;
+                                itemSizes = CryptMemRealloc(itemSizes, capacity * sizeof(struct AsnArrayItemSize));
                             }
                             if (itemSizes)
                             {