nft_mnl_socket_reopen() was introduced to deal with the EINTR case. By reopening the netlink socket, pending netlink messages that are part part of a stale netlink dump are implicitly drop. This patch replaces the nft_mnl_socket_reopen() strategy by pulling out all of the remaining netlink message to restart in a clean state. This is implicitly fixing up a bug in the table ownership support, which assumes that the netlink socket remains open until nft_ctx_free() is invoked. Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> --- include/mnl.h | 1 - src/mnl.c | 20 +++++++++++--------- src/rule.c | 5 ++--- 3 files changed, 13 insertions(+), 13 deletions(-) diff --git a/include/mnl.h b/include/mnl.h index 74b1b56fd686..979929c31c17 100644 --- a/include/mnl.h +++ b/include/mnl.h @@ -7,7 +7,6 @@ #include <libmnl/libmnl.h> struct mnl_socket *nft_mnl_socket_open(void); -struct mnl_socket *nft_mnl_socket_reopen(struct mnl_socket *nf_sock); uint32_t mnl_seqnum_alloc(uint32_t *seqnum); uint32_t mnl_genid_get(struct netlink_ctx *ctx); diff --git a/src/mnl.c b/src/mnl.c index 84cfb2380f55..2ae69c6f185e 100644 --- a/src/mnl.c +++ b/src/mnl.c @@ -52,13 +52,6 @@ struct mnl_socket *nft_mnl_socket_open(void) return nf_sock; } -struct mnl_socket *nft_mnl_socket_reopen(struct mnl_socket *nf_sock) -{ - mnl_socket_close(nf_sock); - - return nft_mnl_socket_open(); -} - uint32_t mnl_seqnum_alloc(unsigned int *seqnum) { return (*seqnum)++; @@ -77,17 +70,26 @@ nft_mnl_recv(struct netlink_ctx *ctx, uint32_t portid, int (*cb)(const struct nlmsghdr *nlh, void *data), void *cb_data) { char buf[NFT_NLMSG_MAXSIZE]; + bool eintr = false; int ret; ret = mnl_socket_recvfrom(ctx->nft->nf_sock, buf, sizeof(buf)); while (ret > 0) { ret = mnl_cb_run(buf, ret, ctx->seqnum, portid, cb, cb_data); - if (ret <= 0) - goto out; + if (ret <= 0) { + if (errno != EINTR) + goto out; + + eintr = true; + } ret = mnl_socket_recvfrom(ctx->nft->nf_sock, buf, sizeof(buf)); } out: + if (eintr) { + ret = -1; + errno = EINTR; + } if (ret < 0 && errno == EAGAIN) return 0; diff --git a/src/rule.c b/src/rule.c index acb10f65a517..367c5c8be952 100644 --- a/src/rule.c +++ b/src/rule.c @@ -292,10 +292,9 @@ replay: ret = cache_init(&ctx, flags); if (ret < 0) { cache_release(cache); - if (errno == EINTR) { - nft->nf_sock = nft_mnl_socket_reopen(nft->nf_sock); + if (errno == EINTR) goto replay; - } + return -1; } -- 2.20.1