From 2f22f0b313f4c11e524c68e34165e62d8276e442 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Tue, 27 Feb 2024 14:30:25 -0800 Subject: tools: ynl: wrap recv() + mnl_cb_run2() into a single helper All callers to mnl_cb_run2() call mnl_socket_recvfrom() right before. Wrap the two in a helper, take typed arguments (struct ynl_parse_arg), instead of hoping that all callers remember that parser error handling requires yarg. In case of ynl_sock_read_family() we will no longer check for kernel returning no data, but that would be a kernel bug, not worth complicating the code to catch this. Calling mnl_cb_run2() on an empty buffer is legal and results in STOP (1). Acked-by: Nicolas Dichtel Link: https://lore.kernel.org/r/20240227223032.1835527-9-kuba@kernel.org Signed-off-by: Jakub Kicinski --- tools/net/ynl/lib/ynl.c | 56 ++++++++++++++++--------------------------------- 1 file changed, 18 insertions(+), 38 deletions(-) (limited to 'tools/net/ynl/lib/ynl.c') diff --git a/tools/net/ynl/lib/ynl.c b/tools/net/ynl/lib/ynl.c index ad77ce6a1128..7c0f404526a0 100644 --- a/tools/net/ynl/lib/ynl.c +++ b/tools/net/ynl/lib/ynl.c @@ -491,6 +491,19 @@ int ynl_cb_null(const struct nlmsghdr *nlh, void *data) return MNL_CB_ERROR; } +static int ynl_sock_read_msgs(struct ynl_parse_arg *yarg, mnl_cb_t cb) +{ + struct ynl_sock *ys = yarg->ys; + ssize_t len; + + len = mnl_socket_recvfrom(ys->sock, ys->rx_buf, MNL_SOCKET_BUFFER_SIZE); + if (len < 0) + return len; + + return mnl_cb_run2(ys->rx_buf, len, ys->seq, ys->portid, + cb, yarg, ynl_cb_array, NLMSG_MIN_TYPE); +} + /* Init/fini and genetlink boiler plate */ static int ynl_get_family_info_mcast(struct ynl_sock *ys, const struct nlattr *mcasts) @@ -572,14 +585,7 @@ static int ynl_sock_read_family(struct ynl_sock *ys, const char *family_name) return err; } - err = mnl_socket_recvfrom(ys->sock, ys->rx_buf, MNL_SOCKET_BUFFER_SIZE); - if (err <= 0) { - perr(ys, "failed to receive the socket family info"); - return err; - } - err = mnl_cb_run2(ys->rx_buf, err, ys->seq, ys->portid, - ynl_get_family_info_cb, &yarg, - ynl_cb_array, ARRAY_SIZE(ynl_cb_array)); + err = ynl_sock_read_msgs(&yarg, ynl_get_family_info_cb); if (err < 0) { free(ys->mcast_groups); perr(ys, "failed to receive the socket family info - no such family?"); @@ -755,7 +761,6 @@ static int ynl_ntf_trampoline(const struct nlmsghdr *nlh, void *data) int ynl_ntf_check(struct ynl_sock *ys) { struct ynl_parse_arg yarg = { .ys = ys, }; - ssize_t len; int err; do { @@ -770,14 +775,7 @@ int ynl_ntf_check(struct ynl_sock *ys) if (err < 1) return err; - len = mnl_socket_recvfrom(ys->sock, ys->rx_buf, - MNL_SOCKET_BUFFER_SIZE); - if (len < 0) - return len; - - err = mnl_cb_run2(ys->rx_buf, len, ys->seq, ys->portid, - ynl_ntf_trampoline, &yarg, - ynl_cb_array, NLMSG_MIN_TYPE); + err = ynl_sock_read_msgs(&yarg, ynl_ntf_trampoline); if (err < 0) return err; } while (err > 0); @@ -834,7 +832,6 @@ static int ynl_req_trampoline(const struct nlmsghdr *nlh, void *data) int ynl_exec(struct ynl_sock *ys, struct nlmsghdr *req_nlh, struct ynl_req_state *yrs) { - ssize_t len; int err; err = mnl_socket_sendto(ys->sock, req_nlh, req_nlh->nlmsg_len); @@ -842,19 +839,10 @@ int ynl_exec(struct ynl_sock *ys, struct nlmsghdr *req_nlh, return err; do { - len = mnl_socket_recvfrom(ys->sock, ys->rx_buf, - MNL_SOCKET_BUFFER_SIZE); - if (len < 0) - return len; - - err = mnl_cb_run2(ys->rx_buf, len, ys->seq, ys->portid, - ynl_req_trampoline, yrs, - ynl_cb_array, NLMSG_MIN_TYPE); - if (err < 0) - return err; + err = ynl_sock_read_msgs(&yrs->yarg, ynl_req_trampoline); } while (err > 0); - return 0; + return err; } static int ynl_dump_trampoline(const struct nlmsghdr *nlh, void *data) @@ -896,7 +884,6 @@ static void *ynl_dump_end(struct ynl_dump_state *ds) int ynl_exec_dump(struct ynl_sock *ys, struct nlmsghdr *req_nlh, struct ynl_dump_state *yds) { - ssize_t len; int err; err = mnl_socket_sendto(ys->sock, req_nlh, req_nlh->nlmsg_len); @@ -904,14 +891,7 @@ int ynl_exec_dump(struct ynl_sock *ys, struct nlmsghdr *req_nlh, return err; do { - len = mnl_socket_recvfrom(ys->sock, ys->rx_buf, - MNL_SOCKET_BUFFER_SIZE); - if (len < 0) - goto err_close_list; - - err = mnl_cb_run2(ys->rx_buf, len, ys->seq, ys->portid, - ynl_dump_trampoline, yds, - ynl_cb_array, NLMSG_MIN_TYPE); + err = ynl_sock_read_msgs(&yds->yarg, ynl_dump_trampoline); if (err < 0) goto err_close_list; } while (err > 0); -- cgit v1.2.3