From 1df417752faf52f17d8ec14578ffde89ced32772 Mon Sep 17 00:00:00 2001 From: Stefano Brivio Date: Wed, 8 Mar 2023 13:21:19 +0100 Subject: [PATCH 15/20] conf: Terminate on EMFILE or ENFILE on sockets for port mapping In general, we don't terminate or report failures if we fail to bind to some ports out of a given port range specifier, to allow users to conveniently specify big port ranges (or "all") without having to care about ports that might already be in use. However, running out of the open file descriptors quota is a different story: we can't do what the user requested in a very substantial way. For example, if the user specifies '-t all' and we can only bind 1024 sockets, the behaviour is rather unexpected. Fail whenever socket creation returns -ENFILE or -EMFILE. Link: https://bugs.passt.top/show_bug.cgi?id=27 Signed-off-by: Stefano Brivio Reviewed-by: David Gibson (cherry picked from commit bb2b67cb3549ea2509f5b7b88790e08d2e362351) --- conf.c | 36 +++++++++++++++++++++++++++++------- 1 file changed, 29 insertions(+), 7 deletions(-) diff --git a/conf.c b/conf.c index 37f25d6..7f25a22 100644 --- a/conf.c +++ b/conf.c @@ -182,6 +182,7 @@ static void conf_ports(const struct ctx *c, char optname, const char *optarg, bool exclude_only = true, bound_one = false; uint8_t exclude[PORT_BITMAP_SIZE] = { 0 }; sa_family_t af = AF_UNSPEC; + int ret; if (!strcmp(optarg, "none")) { if (fwd->mode) @@ -216,11 +217,18 @@ static void conf_ports(const struct ctx *c, char optname, const char *optarg, for (i = 0; i < PORT_EPHEMERAL_MIN; i++) { if (optname == 't') { - if (!tcp_sock_init(c, AF_UNSPEC, NULL, NULL, i)) + ret = tcp_sock_init(c, AF_UNSPEC, NULL, NULL, + i); + if (ret == -ENFILE || ret == -EMFILE) + goto enfile; + if (!ret) bound_one = true; } else if (optname == 'u') { - if (!udp_sock_init(c, 0, AF_UNSPEC, NULL, NULL, - i)) + ret = udp_sock_init(c, 0, AF_UNSPEC, NULL, NULL, + i); + if (ret == -ENFILE || ret == -EMFILE) + goto enfile; + if (!ret) bound_one = true; } } @@ -301,10 +309,16 @@ static void conf_ports(const struct ctx *c, char optname, const char *optarg, bitmap_set(fwd->map, i); if (optname == 't') { - if (!tcp_sock_init(c, af, addr, ifname, i)) + ret = tcp_sock_init(c, af, addr, ifname, i); + if (ret == -ENFILE || ret == -EMFILE) + goto enfile; + if (!ret) bound_one = true; } else if (optname == 'u') { - if (!udp_sock_init(c, 0, af, addr, ifname, i)) + ret = udp_sock_init(c, 0, af, addr, ifname, i); + if (ret == -ENFILE || ret == -EMFILE) + goto enfile; + if (!ret) bound_one = true; } else { /* No way to check in advance for -T and -U */ @@ -356,10 +370,16 @@ static void conf_ports(const struct ctx *c, char optname, const char *optarg, fwd->delta[i] = mapped_range.first - orig_range.first; if (optname == 't') { - if (!tcp_sock_init(c, af, addr, ifname, i)) + ret = tcp_sock_init(c, af, addr, ifname, i); + if (ret == -ENFILE || ret == -EMFILE) + goto enfile; + if (!ret) bound_one = true; } else if (optname == 'u') { - if (!udp_sock_init(c, 0, af, addr, ifname, i)) + ret = udp_sock_init(c, 0, af, addr, ifname, i); + if (ret == -ENFILE || ret == -EMFILE) + goto enfile; + if (!ret) bound_one = true; } else { /* No way to check in advance for -T and -U */ @@ -372,6 +392,8 @@ static void conf_ports(const struct ctx *c, char optname, const char *optarg, goto bind_fail; return; +enfile: + die("Can't open enough sockets for port specifier: %s", optarg); bad: die("Invalid port specifier %s", optarg); overlap: -- 2.39.2