Mercurial > hg > nginx
view src/os/unix/ngx_socket.c @ 9112:d59277dd3d8c
QUIC: fixed post-close use-after-free.
Previously, ngx_quic_close_connection() could be called in a way that QUIC
connection was accessed after the call. In most cases the connection is not
closed right away, but close timeout is scheduled. However, it's not always
the case. Also, if the close process started earlier for a different reason,
calling ngx_quic_close_connection() may actually close the connection. The
connection object should not be accessed after that.
Now, when possible, return statement is added to eliminate post-close connection
object access. In other places ngx_quic_close_connection() is substituted with
posting close event.
Also, the new way of closing connection in ngx_quic_stream_cleanup_handler()
fixes another problem in this function. Previously it passed stream connection
instead of QUIC connection to ngx_quic_close_connection(). This could result
in incomplete connection shutdown. One consequence of that could be that QUIC
streams were freed without shutting down their application contexts. This could
result in another use-after-free.
Found by Coverity (CID 1530402).
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 22 May 2023 15:59:42 +0400 |
parents | d620f497c50f |
children |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> /* * ioctl(FIONBIO) sets a non-blocking mode with the single syscall * while fcntl(F_SETFL, O_NONBLOCK) needs to learn the current state * using fcntl(F_GETFL). * * ioctl() and fcntl() are syscalls at least in FreeBSD 2.x, Linux 2.2 * and Solaris 7. * * ioctl() in Linux 2.4 and 2.6 uses BKL, however, fcntl(F_SETFL) uses it too. */ #if (NGX_HAVE_FIONBIO) int ngx_nonblocking(ngx_socket_t s) { int nb; nb = 1; return ioctl(s, FIONBIO, &nb); } int ngx_blocking(ngx_socket_t s) { int nb; nb = 0; return ioctl(s, FIONBIO, &nb); } #endif #if (NGX_FREEBSD) int ngx_tcp_nopush(ngx_socket_t s) { int tcp_nopush; tcp_nopush = 1; return setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (const void *) &tcp_nopush, sizeof(int)); } int ngx_tcp_push(ngx_socket_t s) { int tcp_nopush; tcp_nopush = 0; return setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (const void *) &tcp_nopush, sizeof(int)); } #elif (NGX_LINUX) int ngx_tcp_nopush(ngx_socket_t s) { int cork; cork = 1; return setsockopt(s, IPPROTO_TCP, TCP_CORK, (const void *) &cork, sizeof(int)); } int ngx_tcp_push(ngx_socket_t s) { int cork; cork = 0; return setsockopt(s, IPPROTO_TCP, TCP_CORK, (const void *) &cork, sizeof(int)); } #else int ngx_tcp_nopush(ngx_socket_t s) { return 0; } int ngx_tcp_push(ngx_socket_t s) { return 0; } #endif