You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
54 lines
1.8 KiB
54 lines
1.8 KiB
2 years ago
|
From c5eed6e541fe27d9e9dfd31f42c43f4dfa1f486b Mon Sep 17 00:00:00 2001
|
||
|
From: Yves Orton <demerphq@gmail.com>
|
||
|
Date: Sat, 11 Jul 2020 09:26:21 +0200
|
||
|
Subject: [PATCH] hv.c: add a guard clause to prevent the number of buckets in
|
||
|
a hash from getting too large
|
||
|
MIME-Version: 1.0
|
||
|
Content-Type: text/plain; charset=UTF-8
|
||
|
Content-Transfer-Encoding: 8bit
|
||
|
|
||
|
This caps it at 1<<28 buckets, eg, ~268M. In theory without a guard clause like
|
||
|
this we could grow to the point of possibly wrapping around in terms of size,
|
||
|
not to mention being ridiculously wasteful of memory at larger sizes.
|
||
|
Even this cap is probably too high. It should probably be something like 1<<24.
|
||
|
|
||
|
Petr Písař: Ported to 5.32.1 from
|
||
|
aae087f7cec022be14a17deb95cb2208e16b7891.
|
||
|
|
||
|
Signed-off-by: Petr Písař <ppisar@redhat.com>
|
||
|
---
|
||
|
hv.c | 10 +++++++++-
|
||
|
1 file changed, 9 insertions(+), 1 deletion(-)
|
||
|
|
||
|
diff --git a/hv.c b/hv.c
|
||
|
index eccae62..32dbd19 100644
|
||
|
--- a/hv.c
|
||
|
+++ b/hv.c
|
||
|
@@ -38,7 +38,13 @@ holds the key and hash value.
|
||
|
* NOTE if you change this formula so we split earlier than previously
|
||
|
* you MUST change the logic in hv_ksplit()
|
||
|
*/
|
||
|
-#define DO_HSPLIT(xhv) ( ((xhv)->xhv_keys + ((xhv)->xhv_keys >> 1)) > (xhv)->xhv_max )
|
||
|
+
|
||
|
+/* MAX_BUCKET_MAX is the maximum max bucket index, at which point we stop growing the
|
||
|
+ * number of buckets,
|
||
|
+ */
|
||
|
+#define MAX_BUCKET_MAX ((1<<26)-1)
|
||
|
+#define DO_HSPLIT(xhv) ( ( ((xhv)->xhv_keys + ((xhv)->xhv_keys >> 1)) > (xhv)->xhv_max ) && \
|
||
|
+ ((xhv)->xhv_max < MAX_BUCKET_MAX) )
|
||
|
#define HV_FILL_THRESHOLD 31
|
||
|
|
||
|
static const char S_strtab_error[]
|
||
|
@@ -1426,6 +1432,8 @@ S_hsplit(pTHX_ HV *hv, STRLEN const oldsize, STRLEN newsize)
|
||
|
);
|
||
|
|
||
|
PERL_ARGS_ASSERT_HSPLIT;
|
||
|
+ if (newsize > MAX_BUCKET_MAX+1)
|
||
|
+ return;
|
||
|
|
||
|
PL_nomemok = TRUE;
|
||
|
Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
|
||
|
--
|
||
|
2.26.2
|
||
|
|