diff options
| author | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-07-17 14:38:37 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-07-17 14:42:50 +0200 |
| commit | efd09355038d53fdd3841ab5ccae1543c4967daf (patch) | |
| tree | 3e0bb61b27fdb8ec4ffe0900cf418e980f811f03 /src | |
| parent | 1ddd74855032015195a8d87c0b650f1ce73db375 (diff) | |
netlink_delinearize: meta l4proto range printing broken on 32bit
Florian Westphal says:
09565a4b1ed4863d44c4509a93c50f44efd12771 ("netlink_delinearize: consolidate
range printing") causes nft to segfault on 32bit machine when printing l4proto
ranges.
The problem is that meta_expr_pctx_update() assumes that right is a value, but
after this change it can also be a range.
Thus, expr->value contents are undefined (its union). On x86_64 this is also
broken but by virtue of struct layout and pointer sizes, value->_mp_size will
almost always be 0 so mpz_get_uint8() returns 0.
But on x86-32 _mp_size will be huge value (contains expr->right pointer of
range), so we crash in libgmp.
Pablo says:
We shouldn't call pctx_update(), before the transformation we had
there a expr->op == { OP_GT, OP_GTE, OP_LT, OP_LTE }. So we never
entered that path as the assert in payload_expr_pctx_update()
indicates.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Tested-by: Florian Westphal <fw@strlen.de>
Diffstat (limited to 'src')
| -rw-r--r-- | src/netlink_delinearize.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/src/netlink_delinearize.c b/src/netlink_delinearize.c index 6d60be32..4226b822 100644 --- a/src/netlink_delinearize.c +++ b/src/netlink_delinearize.c @@ -983,6 +983,9 @@ static void meta_match_postprocess(struct rule_pp_ctx *ctx, switch (expr->op) { case OP_EQ: + if (expr->right->ops->type == EXPR_RANGE) + break; + expr->left->ops->pctx_update(&ctx->pctx, expr); if (ctx->pbase == PROTO_BASE_INVALID && |