[dpdk-dev] [PATCH] lib/table: fix table autotest ut crashes in ipv6

[David Marchand]

On Tue, Jul 2, 2019 at 1:22 PM Jananee Parthasarathy <
jananeex.m.parthasarathy at intel.com> wrote:

> Unit test table_autotest results in segmentation fault.
> Crash occurs in test_table_lpm_ipv6_combined().
>
> Variable 'nht_pos0' used as array subscript is not initialized
> in rte_table_lpm_ipv6_entry_add(). It will not be assigned,
> if a rule does not exist.
>
> In such case a junk number or invalid array index might result in
> segmentation fault due to array out of bounds when
> lpm->nht_users is used with such invalid array index.
>
> Fix is to initialize the variables used for array subscript.
>
>
Bugzilla ID: 285

Fixes: d89a5bce1d ("lpm6: extend next hop field")
> Cc: stable at dpdk.org
>
> Signed-off-by: Jananee Parthasarathy <jananeex.m.parthasarathy at intel.com>
> ---
>  lib/librte_table/rte_table_lpm_ipv6.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/librte_table/rte_table_lpm_ipv6.c
> b/lib/librte_table/rte_table_lpm_ipv6.c
> index a55f808a4..4e068d79b 100644
> --- a/lib/librte_table/rte_table_lpm_ipv6.c
> +++ b/lib/librte_table/rte_table_lpm_ipv6.c
> @@ -182,7 +182,7 @@ rte_table_lpm_ipv6_entry_add(
>         struct rte_table_lpm_ipv6 *lpm = table;
>         struct rte_table_lpm_ipv6_key *ip_prefix =
>                 key;
> -       uint32_t nht_pos, nht_pos0, nht_pos0_valid;
> +       uint32_t nht_pos = 0, nht_pos0 = 0, nht_pos0_valid = 0;
>

nht_pos_valid is unconditionnally set, no need to initialize.
Just noticed that nht_pos is not initialised to 0 in ipv4 code.

It fixes the segfault I saw, leaving the ack to the maintainer.
Tested-by: David Marchand <david.marchand at redhat.com>

-- 
David Marchand