From b65ce380b754e77fbfdcfc83fd6e29c8ceedf431 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Fri, 12 Jun 2020 00:16:55 -0700 Subject: genetlink: clean up family attributes allocations genl_family_rcv_msg_attrs_parse() and genl_family_rcv_msg_attrs_free() take a boolean parameter to determine whether allocate/free the family attrs. This is unnecessary as we can just check family->parallel_ops. More importantly, callers would not need to worry about pairing these parameters correctly after this patch. And this fixes a memory leak, as after commit c36f05559104 ("genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()") we call genl_family_rcv_msg_attrs_parse() for both parallel and non-parallel cases. Fixes: c36f05559104 ("genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()") Reported-by: Ido Schimmel Signed-off-by: Cong Wang Reviewed-by: Ido Schimmel Tested-by: Ido Schimmel Signed-off-by: David S. Miller --- net/netlink/genetlink.c | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 6c19b91bbb86..55ee680e9db1 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -474,8 +474,7 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family *family, struct netlink_ext_ack *extack, const struct genl_ops *ops, int hdrlen, - enum genl_validate_flags no_strict_flag, - bool parallel) + enum genl_validate_flags no_strict_flag) { enum netlink_validation validate = ops->validate & no_strict_flag ? NL_VALIDATE_LIBERAL : @@ -486,7 +485,7 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family *family, if (!family->maxattr) return NULL; - if (parallel) { + if (family->parallel_ops) { attrbuf = kmalloc_array(family->maxattr + 1, sizeof(struct nlattr *), GFP_KERNEL); if (!attrbuf) @@ -498,7 +497,7 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family *family, err = __nlmsg_parse(nlh, hdrlen, attrbuf, family->maxattr, family->policy, validate, extack); if (err) { - if (parallel) + if (family->parallel_ops) kfree(attrbuf); return ERR_PTR(err); } @@ -506,10 +505,9 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family *family, } static void genl_family_rcv_msg_attrs_free(const struct genl_family *family, - struct nlattr **attrbuf, - bool parallel) + struct nlattr **attrbuf) { - if (parallel) + if (family->parallel_ops) kfree(attrbuf); } @@ -537,15 +535,14 @@ static int genl_start(struct netlink_callback *cb) attrs = genl_family_rcv_msg_attrs_parse(ctx->family, ctx->nlh, ctx->extack, ops, ctx->hdrlen, - GENL_DONT_VALIDATE_DUMP_STRICT, - true); + GENL_DONT_VALIDATE_DUMP_STRICT); if (IS_ERR(attrs)) return PTR_ERR(attrs); no_attrs: info = genl_dumpit_info_alloc(); if (!info) { - kfree(attrs); + genl_family_rcv_msg_attrs_free(ctx->family, attrs); return -ENOMEM; } info->family = ctx->family; @@ -562,7 +559,7 @@ no_attrs: } if (rc) { - kfree(attrs); + genl_family_rcv_msg_attrs_free(info->family, info->attrs); genl_dumpit_info_free(info); cb->data = NULL; } @@ -591,7 +588,7 @@ static int genl_lock_done(struct netlink_callback *cb) rc = ops->done(cb); genl_unlock(); } - genl_family_rcv_msg_attrs_free(info->family, info->attrs, false); + genl_family_rcv_msg_attrs_free(info->family, info->attrs); genl_dumpit_info_free(info); return rc; } @@ -604,7 +601,7 @@ static int genl_parallel_done(struct netlink_callback *cb) if (ops->done) rc = ops->done(cb); - genl_family_rcv_msg_attrs_free(info->family, info->attrs, true); + genl_family_rcv_msg_attrs_free(info->family, info->attrs); genl_dumpit_info_free(info); return rc; } @@ -671,8 +668,7 @@ static int genl_family_rcv_msg_doit(const struct genl_family *family, attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack, ops, hdrlen, - GENL_DONT_VALIDATE_STRICT, - family->parallel_ops); + GENL_DONT_VALIDATE_STRICT); if (IS_ERR(attrbuf)) return PTR_ERR(attrbuf); @@ -698,7 +694,7 @@ static int genl_family_rcv_msg_doit(const struct genl_family *family, family->post_doit(ops, skb, &info); out: - genl_family_rcv_msg_attrs_free(family, attrbuf, family->parallel_ops); + genl_family_rcv_msg_attrs_free(family, attrbuf); return err; } -- cgit v1.2.3