4.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Herbert Xu <herb...@gondor.apana.org.au>
[ Upstream commit 3a324606bbabfc30084ce9d08169910773ba9a92 ]
William Hua <william....@canonical.com> wrote:
>
> I wasn't aware there was an enforced minimum size. I simply set the
> nelem_hint in the rhastable_params struct to 1, expecting it to grow as
> needed. This caused a segfault afterwards when trying to insert an
> element.
OK we're doing the size computation before we enforce the limit
on min_size.
---8<---
We need to do the initial hash table size computation after we
have obtained the correct min_size/max_size parameters. Otherwise
we may end up with a hash table whose size is outside the allowed
envelope.
Fixes: a998f712f77e ("rhashtable: Round up/down min/max_size to...")
Reported-by: William Hua <william....@canonical.com>
Signed-off-by: Herbert Xu <herb...@gondor.apana.org.au>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
lib/rhashtable.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -730,9 +730,6 @@ int rhashtable_init(struct rhashtable *h
if (params->nulls_base && params->nulls_base < (1U << RHT_BASE_SHIFT))
return -EINVAL;
- if (params->nelem_hint)
- size = rounded_hashtable_size(params);
-
memset(ht, 0, sizeof(*ht));
mutex_init(&ht->mutex);
spin_lock_init(&ht->lock);
@@ -752,6 +749,9 @@ int rhashtable_init(struct rhashtable *h
ht->p.min_size = max(ht->p.min_size, HASH_MIN_SIZE);
+ if (params->nelem_hint)
+ size = rounded_hashtable_size(&ht->p);
+
/* The maximum (not average) chain length grows with the
* size of the hash table, at a rate of (log N)/(log log N).
* The value of 16 is selected so that even if the hash
