Mercurial > hg > nginx
view src/os/unix/ngx_user.c @ 7048:80224192163c
Resolver: fixed possible use-after-free while resolving SRV.
Resolving an SRV record includes resolving its host names in subrequests.
Previously, if memory allocation failed while reporting a subrequest result
after receiving a response from a DNS server, the SRV resolve handler was
called immediately with the NGX_ERROR state. However, if the SRV record
included another copy of the resolved name, it was reported once again.
This could trigger the use-after-free memory access after SRV resolve
handler freed the resolve context by calling ngx_resolve_name_done().
Now the SRV resolve handler is called only when all its subrequests are
completed.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Tue, 04 Jul 2017 18:07:29 +0300 |
parents | e284f3ff6831 |
children | 4a670c18e5e6 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> /* * Solaris has thread-safe crypt() * Linux has crypt_r(); "struct crypt_data" is more than 128K * FreeBSD needs the mutex to protect crypt() * * TODO: * ngx_crypt_init() to init mutex */ #if (NGX_CRYPT) #if (NGX_HAVE_GNU_CRYPT_R) ngx_int_t ngx_libc_crypt(ngx_pool_t *pool, u_char *key, u_char *salt, u_char **encrypted) { char *value; size_t len; struct crypt_data cd; cd.initialized = 0; #ifdef __GLIBC__ /* work around the glibc bug */ cd.current_salt[0] = ~salt[0]; #endif value = crypt_r((char *) key, (char *) salt, &cd); if (value) { len = ngx_strlen(value) + 1; *encrypted = ngx_pnalloc(pool, len); if (*encrypted == NULL) { return NGX_ERROR; } ngx_memcpy(*encrypted, value, len); return NGX_OK; } ngx_log_error(NGX_LOG_CRIT, pool->log, ngx_errno, "crypt_r() failed"); return NGX_ERROR; } #else ngx_int_t ngx_libc_crypt(ngx_pool_t *pool, u_char *key, u_char *salt, u_char **encrypted) { char *value; size_t len; ngx_err_t err; value = crypt((char *) key, (char *) salt); if (value) { len = ngx_strlen(value) + 1; *encrypted = ngx_pnalloc(pool, len); if (*encrypted == NULL) { return NGX_ERROR; } ngx_memcpy(*encrypted, value, len); return NGX_OK; } err = ngx_errno; ngx_log_error(NGX_LOG_CRIT, pool->log, err, "crypt() failed"); return NGX_ERROR; } #endif #endif /* NGX_CRYPT */