Merge branch 'bug16288_027_03_squashed'

This commit is contained in:
Nick Mathewson 2015-06-25 11:30:52 -04:00
commit 3149bfc254
4 changed files with 69 additions and 27 deletions

6
changes/bug16288 Normal file
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@ -0,0 +1,6 @@
o Major bugfixes (open file limit):
- The max open file limit wasn't checked before calling
tor_accept_socket_nonblocking() which made tor go beyond the open
file limit set previously. With this fix, before opening a new socket,
tor validates the open file limit just before and if the max has been
reached, return EMFILE.; Fixes #16288; bugfix on tor-0.1.1.1-alpha~74.

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@ -138,6 +138,11 @@
#include "strlcat.c"
#endif
/* When set_max_file_descriptors() is called, update this with the max file
* descriptor value so we can use it to check the limit when opening a new
* socket. Default value is what Debian sets as the default hard limit. */
static int max_sockets = 1024;
/** As open(path, flags, mode), but return an fd with the close-on-exec mode
* set. */
int
@ -1194,6 +1199,18 @@ tor_open_socket_with_extensions(int domain, int type, int protocol,
int cloexec, int nonblock)
{
tor_socket_t s;
/* We are about to create a new file descriptor so make sure we have
* enough of them. */
if (get_n_open_sockets() >= max_sockets - 1) {
#ifdef _WIN32
WSASetLastError(WSAEMFILE);
#else
errno = EMFILE;
#endif
return TOR_INVALID_SOCKET;
}
#if defined(SOCK_CLOEXEC) && defined(SOCK_NONBLOCK)
int ext_flags = (cloexec ? SOCK_CLOEXEC : 0) |
(nonblock ? SOCK_NONBLOCK : 0);
@ -1265,6 +1282,18 @@ tor_accept_socket_with_extensions(tor_socket_t sockfd, struct sockaddr *addr,
socklen_t *len, int cloexec, int nonblock)
{
tor_socket_t s;
/* We are about to create a new file descriptor so make sure we have
* enough of them. */
if (get_n_open_sockets() >= max_sockets - 1) {
#ifdef _WIN32
WSASetLastError(WSAEMFILE);
#else
errno = EMFILE;
#endif
return TOR_INVALID_SOCKET;
}
#if defined(HAVE_ACCEPT4) && defined(SOCK_CLOEXEC) && defined(SOCK_NONBLOCK)
int ext_flags = (cloexec ? SOCK_CLOEXEC : 0) |
(nonblock ? SOCK_NONBLOCK : 0);
@ -1560,6 +1589,12 @@ tor_ersatz_socketpair(int family, int type, int protocol, tor_socket_t fd[2])
int
set_max_file_descriptors(rlim_t limit, int *max_out)
{
if (limit < ULIMIT_BUFFER) {
log_warn(LD_CONFIG,
"ConnLimit must be at least %d. Failing.", ULIMIT_BUFFER);
return -1;
}
/* Define some maximum connections values for systems where we cannot
* automatically determine a limit. Re Cygwin, see
* http://archives.seul.org/or/talk/Aug-2006/msg00210.html
@ -1599,7 +1634,7 @@ set_max_file_descriptors(rlim_t limit, int *max_out)
limit = rlim.rlim_max;
if (limit > INT_MAX)
limit = INT_MAX;
*max_out = (int)limit - ULIMIT_BUFFER;
*max_out = max_sockets = (int)limit - ULIMIT_BUFFER;
return 0;
}
if (rlim.rlim_max < limit) {
@ -1613,6 +1648,9 @@ set_max_file_descriptors(rlim_t limit, int *max_out)
log_info(LD_NET,"Raising max file descriptors from %lu to %lu.",
(unsigned long)rlim.rlim_cur, (unsigned long)rlim.rlim_max);
}
/* Set the current limit value so if the attempt to set the limit to the
* max fails at least we'll have a valid value of maximum sockets. */
max_sockets = rlim.rlim_cur - ULIMIT_BUFFER;
rlim.rlim_cur = rlim.rlim_max;
if (setrlimit(RLIMIT_NOFILE, &rlim) != 0) {
@ -1646,15 +1684,10 @@ set_max_file_descriptors(rlim_t limit, int *max_out)
limit = rlim.rlim_cur;
#endif /* HAVE_GETRLIMIT */
if (limit < ULIMIT_BUFFER) {
log_warn(LD_CONFIG,
"ConnLimit must be at least %d. Failing.", ULIMIT_BUFFER);
return -1;
}
if (limit > INT_MAX)
limit = INT_MAX;
tor_assert(max_out);
*max_out = (int)limit - ULIMIT_BUFFER;
*max_out = max_sockets = (int)limit - ULIMIT_BUFFER;
return 0;
}

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@ -580,7 +580,7 @@ int network_init(void);
#define ERRNO_IS_ACCEPT_EAGAIN(e) ERRNO_IS_EAGAIN(e)
/** Return true if e is EMFILE or another error indicating that a call to
* accept() has failed because we're out of fds or something. */
#define ERRNO_IS_ACCEPT_RESOURCE_LIMIT(e) \
#define ERRNO_IS_RESOURCE_LIMIT(e) \
((e) == WSAEMFILE || (e) == WSAENOBUFS)
/** Return true if e is EADDRINUSE or the local equivalent. */
#define ERRNO_IS_EADDRINUSE(e) ((e) == WSAEADDRINUSE)
@ -598,7 +598,7 @@ const char *tor_socket_strerror(int e);
#define ERRNO_IS_CONN_EINPROGRESS(e) ((e) == EINPROGRESS || 0)
#define ERRNO_IS_ACCEPT_EAGAIN(e) \
(ERRNO_IS_EAGAIN(e) || (e) == ECONNABORTED)
#define ERRNO_IS_ACCEPT_RESOURCE_LIMIT(e) \
#define ERRNO_IS_RESOURCE_LIMIT(e) \
((e) == EMFILE || (e) == ENFILE || (e) == ENOBUFS || (e) == ENOMEM)
#define ERRNO_IS_EADDRINUSE(e) (((e) == EADDRINUSE) || 0)
#define tor_socket_errno(sock) (errno)

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@ -1093,11 +1093,6 @@ connection_listener_new(const struct sockaddr *listensockaddr,
static int global_next_session_group = SESSION_GROUP_FIRST_AUTO;
tor_addr_t addr;
if (get_n_open_sockets() >= options->ConnLimit_-1) {
warn_too_many_conns();
return NULL;
}
if (listensockaddr->sa_family == AF_INET ||
listensockaddr->sa_family == AF_INET6) {
int is_stream = (type != CONN_TYPE_AP_DNS_LISTENER);
@ -1113,8 +1108,13 @@ connection_listener_new(const struct sockaddr *listensockaddr,
is_stream ? SOCK_STREAM : SOCK_DGRAM,
is_stream ? IPPROTO_TCP: IPPROTO_UDP);
if (!SOCKET_OK(s)) {
log_warn(LD_NET, "Socket creation failed: %s",
tor_socket_strerror(tor_socket_errno(-1)));
int e = tor_socket_errno(s);
if (ERRNO_IS_RESOURCE_LIMIT(e)) {
warn_too_many_conns();
} else {
log_warn(LD_NET, "Socket creation failed: %s",
tor_socket_strerror(e));
}
goto err;
}
@ -1222,7 +1222,12 @@ connection_listener_new(const struct sockaddr *listensockaddr,
s = tor_open_socket_nonblocking(AF_UNIX, SOCK_STREAM, 0);
if (! SOCKET_OK(s)) {
log_warn(LD_NET,"Socket creation failed: %s.", strerror(errno));
int e = tor_socket_errno(s);
if (ERRNO_IS_RESOURCE_LIMIT(e)) {
warn_too_many_conns();
} else {
log_warn(LD_NET,"Socket creation failed: %s.", strerror(e));
}
goto err;
}
@ -1430,7 +1435,7 @@ connection_handle_listener_read(connection_t *conn, int new_type)
int e = tor_socket_errno(conn->s);
if (ERRNO_IS_ACCEPT_EAGAIN(e)) {
return 0; /* he hung up before we could accept(). that's fine. */
} else if (ERRNO_IS_ACCEPT_RESOURCE_LIMIT(e)) {
} else if (ERRNO_IS_RESOURCE_LIMIT(e)) {
warn_too_many_conns();
return 0;
}
@ -1624,12 +1629,6 @@ connection_connect_sockaddr(connection_t *conn,
tor_assert(sa);
tor_assert(socket_error);
if (get_n_open_sockets() >= get_options()->ConnLimit_-1) {
warn_too_many_conns();
*socket_error = SOCK_ERRNO(ENOBUFS);
return -1;
}
if (get_options()->DisableNetwork) {
/* We should never even try to connect anyplace if DisableNetwork is set.
* Warn if we do, and refuse to make the connection. */
@ -1647,9 +1646,13 @@ connection_connect_sockaddr(connection_t *conn,
s = tor_open_socket_nonblocking(protocol_family, SOCK_STREAM, proto);
if (! SOCKET_OK(s)) {
*socket_error = tor_socket_errno(-1);
log_warn(LD_NET,"Error creating network socket: %s",
tor_socket_strerror(*socket_error));
*socket_error = tor_socket_errno(s);
if (ERRNO_IS_RESOURCE_LIMIT(*socket_error)) {
warn_too_many_conns();
} else {
log_warn(LD_NET,"Error creating network socket: %s",
tor_socket_strerror(*socket_error));
}
return -1;
}