Mercurial > hg > nginx
view src/core/ngx_shmtx.h @ 7566:571383f75a9a
Resolver: fixed possible use-after-free while resolving PTR.
Previously, if a response to the PTR request was cached, and ngx_resolver_dup()
failed to allocate memory for the resulting name, then the original node was
freed but left in expire_queue. A subsequent address resolving would end up
in a use-after-free memory access of the node either in ngx_resolver_expire()
or ngx_resolver_process_ptr(), when accessing it through expire_queue.
The fix is to leave the resolver node intact.
author | Sergey Kandaurov <pluknet@nginx.com> |
---|---|
date | Tue, 10 Sep 2019 15:42:34 +0300 |
parents | 512c741fa841 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_SHMTX_H_INCLUDED_ #define _NGX_SHMTX_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> typedef struct { ngx_atomic_t lock; #if (NGX_HAVE_POSIX_SEM) ngx_atomic_t wait; #endif } ngx_shmtx_sh_t; typedef struct { #if (NGX_HAVE_ATOMIC_OPS) ngx_atomic_t *lock; #if (NGX_HAVE_POSIX_SEM) ngx_atomic_t *wait; ngx_uint_t semaphore; sem_t sem; #endif #else ngx_fd_t fd; u_char *name; #endif ngx_uint_t spin; } ngx_shmtx_t; ngx_int_t ngx_shmtx_create(ngx_shmtx_t *mtx, ngx_shmtx_sh_t *addr, u_char *name); void ngx_shmtx_destroy(ngx_shmtx_t *mtx); ngx_uint_t ngx_shmtx_trylock(ngx_shmtx_t *mtx); void ngx_shmtx_lock(ngx_shmtx_t *mtx); void ngx_shmtx_unlock(ngx_shmtx_t *mtx); ngx_uint_t ngx_shmtx_force_unlock(ngx_shmtx_t *mtx, ngx_pid_t pid); #endif /* _NGX_SHMTX_H_INCLUDED_ */