Mercurial > hg > nginx-quic
view src/os/unix/ngx_time.c @ 7400:be5cb9c67c05
Mp4: fixed possible pointer overflow on 32-bit platforms.
On 32-bit platforms mp4->buffer_pos might overflow when a large
enough (close to 4 gigabytes) atom is being skipped, resulting in
incorrect memory addesses being read further in the code. In most
cases this results in harmless errors being logged, though may also
result in a segmentation fault if hitting unmapped pages.
To address this, ngx_mp4_atom_next() now only increments mp4->buffer_pos
up to mp4->buffer_end. This ensures that overflow cannot happen.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 21 Nov 2018 20:23:16 +0300 |
parents | d620f497c50f |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> /* * FreeBSD does not test /etc/localtime change, however, we can workaround it * by calling tzset() with TZ and then without TZ to update timezone. * The trick should work since FreeBSD 2.1.0. * * Linux does not test /etc/localtime change in localtime(), * but may stat("/etc/localtime") several times in every strftime(), * therefore we use it to update timezone. * * Solaris does not test /etc/TIMEZONE change too and no workaround available. */ void ngx_timezone_update(void) { #if (NGX_FREEBSD) if (getenv("TZ")) { return; } putenv("TZ=UTC"); tzset(); unsetenv("TZ"); tzset(); #elif (NGX_LINUX) time_t s; struct tm *t; char buf[4]; s = time(0); t = localtime(&s); strftime(buf, 4, "%H", t); #endif } void ngx_localtime(time_t s, ngx_tm_t *tm) { #if (NGX_HAVE_LOCALTIME_R) (void) localtime_r(&s, tm); #else ngx_tm_t *t; t = localtime(&s); *tm = *t; #endif tm->ngx_tm_mon++; tm->ngx_tm_year += 1900; } void ngx_libc_localtime(time_t s, struct tm *tm) { #if (NGX_HAVE_LOCALTIME_R) (void) localtime_r(&s, tm); #else struct tm *t; t = localtime(&s); *tm = *t; #endif } void ngx_libc_gmtime(time_t s, struct tm *tm) { #if (NGX_HAVE_LOCALTIME_R) (void) gmtime_r(&s, tm); #else struct tm *t; t = gmtime(&s); *tm = *t; #endif }