diff options
| author | Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com> | 2020-10-20 13:41:36 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-11-01 12:01:01 +0100 |
| commit | bded4de4a5e13036a1589e9d5939b4d420479c0d (patch) | |
| tree | 14804977ce898e575dd1b04eddb6736595f32a92 /net | |
| parent | bde3f94035b0e5a724853544d65d00536e1889b2 (diff) | |
netfilter: nftables_offload: KASAN slab-out-of-bounds Read in nft_flow_rule_create
commit 31cc578ae2de19c748af06d859019dced68e325d upstream.
This patch fixes the issue due to:
BUG: KASAN: slab-out-of-bounds in nft_flow_rule_create+0x622/0x6a2
net/netfilter/nf_tables_offload.c:40
Read of size 8 at addr ffff888103910b58 by task syz-executor227/16244
The error happens when expr->ops is accessed early on before performing the boundary check and after nft_expr_next() moves the expr to go out-of-bounds.
This patch checks the boundary condition before expr->ops that fixes the slab-out-of-bounds Read issue.
Add nft_expr_more() and use it to fix this problem.
Signed-off-by: Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/nf_tables_api.c | 6 | ||||
| -rw-r--r-- | net/netfilter/nf_tables_offload.c | 4 |
2 files changed, 5 insertions, 5 deletions
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index ff2d2b514506..5a77b7a17722 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -254,7 +254,7 @@ static void nft_rule_expr_activate(const struct nft_ctx *ctx, struct nft_expr *expr; expr = nft_expr_first(rule); - while (expr != nft_expr_last(rule) && expr->ops) { + while (nft_expr_more(rule, expr)) { if (expr->ops->activate) expr->ops->activate(ctx, expr); @@ -269,7 +269,7 @@ static void nft_rule_expr_deactivate(const struct nft_ctx *ctx, struct nft_expr *expr; expr = nft_expr_first(rule); - while (expr != nft_expr_last(rule) && expr->ops) { + while (nft_expr_more(rule, expr)) { if (expr->ops->deactivate) expr->ops->deactivate(ctx, expr, phase); @@ -2642,7 +2642,7 @@ static void nf_tables_rule_destroy(const struct nft_ctx *ctx, * is called on error from nf_tables_newrule(). */ expr = nft_expr_first(rule); - while (expr != nft_expr_last(rule) && expr->ops) { + while (nft_expr_more(rule, expr)) { next = nft_expr_next(expr); nf_tables_expr_destroy(ctx, expr); expr = next; diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c index 914cd0618d5a..c480549a7f94 100644 --- a/net/netfilter/nf_tables_offload.c +++ b/net/netfilter/nf_tables_offload.c @@ -37,7 +37,7 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *net, struct nft_expr *expr; expr = nft_expr_first(rule); - while (expr->ops && expr != nft_expr_last(rule)) { + while (nft_expr_more(rule, expr)) { if (expr->ops->offload_flags & NFT_OFFLOAD_F_ACTION) num_actions++; @@ -61,7 +61,7 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *net, ctx->net = net; ctx->dep.type = NFT_OFFLOAD_DEP_UNSPEC; - while (expr->ops && expr != nft_expr_last(rule)) { + while (nft_expr_more(rule, expr)) { if (!expr->ops->offload) { err = -EOPNOTSUPP; goto err_out; |