| Message ID | 20170427223024.32657-1-f.fainelli@gmail.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 751630bbe409..6b4f07760fec 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -963,7 +963,7 @@ int rhashtable_init(struct rhashtable *ht, /* Cap total entries at 2^31 to avoid nelems overflow. */ ht->max_elems = 1u << 31; - if (ht->p.max_size < ht->max_elems / 2) + if (ht->p.max_size && (ht->p.max_size < ht->max_elems / 2)) ht->max_elems = ht->p.max_size * 2; ht->p.min_size = max(ht->p.min_size, HASH_MIN_SIZE);
After commit 6d684e54690c ("rhashtable: Cap total number of entries to 2^31"), we would be hitting a panic() in net/core/rtnetlink.c during initialization. The call stack would look like this: register_pernet_subsys() ... ops->init() rtnetlink_net_init() netlink_kernel_create() netlink_insert() __netlink_insert() rhashtable_lookup_insert_key() __rhashtable_insert_fast() rht_grow_above_max() And here, we have rht_grow_above_max() return true, because ht->nelemts = 0 (legit) && ht->max_elems = 0 (looks bogus). Eventually, we would be return -E2BIG from __rhashtable_insert_fast() and propagate this all the way back to the caller. After commit 6d684e54690c what changed is that we would take the following condition: if (ht->p.max_size < ht->max_elems / 2) ht->max_elems = ht->p.max_size * 2; and since ht->p.max_size = 0, we would set ht->max_elems to 0 as well. Fix this by taking this branch only when ht->p.max_size is non-zero Fixes: Fixes: 6d684e54690c ("rhashtable: Cap total number of entries to 2^31") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> --- lib/rhashtable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)