4.19-stable review patch. If anyone has any objections, please let me know.
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From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
commit 753c111f655e38bbd52fc01321266633f022ebe2 upstream.
Fetch pointer to module before target object is released.
Fixes: 29e3880109e3 ("netfilter: nf_tables: fix use-after-free when deleting compat expressions")
Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netfilter/nft_compat.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -282,6 +282,7 @@ nft_target_destroy(const struct nft_ctx
{
struct xt_target *target = expr->ops->data;
void *info = nft_expr_priv(expr);
+ struct module *me = target->me;
struct xt_tgdtor_param par;
par.net = ctx->net;
@@ -292,7 +293,7 @@ nft_target_destroy(const struct nft_ctx
par.target->destroy(&par);
if (nft_xt_put(container_of(expr->ops, struct nft_xt, ops)))
- module_put(target->me);
+ module_put(me);
}
static int nft_target_dump(struct sk_buff *skb, const struct nft_expr *expr)
