Mercurial > hg > nginx
view src/core/ngx_palloc.c @ 6874:7cc2d3a96ea3
Fixed trailer construction with limit on FreeBSD and macOS.
The ngx_chain_coalesce_file() function may produce more bytes to send then
requested in the limit passed, as it aligns the last file position
to send to memory page boundary. As a result, (limit - send) may become
negative. This resulted in big positive number when converted to size_t
while calling ngx_output_chain_to_iovec().
Another part of the problem is in ngx_chain_coalesce_file(): it changes cl
to the next chain link even if the current buffer is only partially sent
due to limit.
Therefore, if a file buffer was not expected to be fully sent due to limit,
and was followed by a memory buffer, nginx called sendfile() with a part
of the file buffer, and the memory buffer in trailer. If there were enough
room in the socket buffer, this resulted in a part of the file buffer being
skipped, and corresponding part of the memory buffer sent instead.
The bug was introduced in 8e903522c17a (1.7.8). Configurations affected
are ones using limits, that is, limit_rate and/or sendfile_max_chunk, and
memory buffers after file ones (may happen when using subrequests or
with proxying with disk buffering).
Fix is to explicitly check if (send < limit) before constructing trailer
with ngx_output_chain_to_iovec(). Additionally, ngx_chain_coalesce_file()
was modified to preserve unfinished file buffers in cl.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Fri, 20 Jan 2017 21:12:48 +0300 |
parents | ad2360782ecd |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> static ngx_inline void *ngx_palloc_small(ngx_pool_t *pool, size_t size, ngx_uint_t align); static void *ngx_palloc_block(ngx_pool_t *pool, size_t size); static void *ngx_palloc_large(ngx_pool_t *pool, size_t size); ngx_pool_t * ngx_create_pool(size_t size, ngx_log_t *log) { ngx_pool_t *p; p = ngx_memalign(NGX_POOL_ALIGNMENT, size, log); if (p == NULL) { return NULL; } p->d.last = (u_char *) p + sizeof(ngx_pool_t); p->d.end = (u_char *) p + size; p->d.next = NULL; p->d.failed = 0; size = size - sizeof(ngx_pool_t); p->max = (size < NGX_MAX_ALLOC_FROM_POOL) ? size : NGX_MAX_ALLOC_FROM_POOL; p->current = p; p->chain = NULL; p->large = NULL; p->cleanup = NULL; p->log = log; return p; } void ngx_destroy_pool(ngx_pool_t *pool) { ngx_pool_t *p, *n; ngx_pool_large_t *l; ngx_pool_cleanup_t *c; for (c = pool->cleanup; c; c = c->next) { if (c->handler) { ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, pool->log, 0, "run cleanup: %p", c); c->handler(c->data); } } #if (NGX_DEBUG) /* * we could allocate the pool->log from this pool * so we cannot use this log while free()ing the pool */ for (l = pool->large; l; l = l->next) { ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, pool->log, 0, "free: %p", l->alloc); } for (p = pool, n = pool->d.next; /* void */; p = n, n = n->d.next) { ngx_log_debug2(NGX_LOG_DEBUG_ALLOC, pool->log, 0, "free: %p, unused: %uz", p, p->d.end - p->d.last); if (n == NULL) { break; } } #endif for (l = pool->large; l; l = l->next) { if (l->alloc) { ngx_free(l->alloc); } } for (p = pool, n = pool->d.next; /* void */; p = n, n = n->d.next) { ngx_free(p); if (n == NULL) { break; } } } void ngx_reset_pool(ngx_pool_t *pool) { ngx_pool_t *p; ngx_pool_large_t *l; for (l = pool->large; l; l = l->next) { if (l->alloc) { ngx_free(l->alloc); } } for (p = pool; p; p = p->d.next) { p->d.last = (u_char *) p + sizeof(ngx_pool_t); p->d.failed = 0; } pool->current = pool; pool->chain = NULL; pool->large = NULL; } void * ngx_palloc(ngx_pool_t *pool, size_t size) { #if !(NGX_DEBUG_PALLOC) if (size <= pool->max) { return ngx_palloc_small(pool, size, 1); } #endif return ngx_palloc_large(pool, size); } void * ngx_pnalloc(ngx_pool_t *pool, size_t size) { #if !(NGX_DEBUG_PALLOC) if (size <= pool->max) { return ngx_palloc_small(pool, size, 0); } #endif return ngx_palloc_large(pool, size); } static ngx_inline void * ngx_palloc_small(ngx_pool_t *pool, size_t size, ngx_uint_t align) { u_char *m; ngx_pool_t *p; p = pool->current; do { m = p->d.last; if (align) { m = ngx_align_ptr(m, NGX_ALIGNMENT); } if ((size_t) (p->d.end - m) >= size) { p->d.last = m + size; return m; } p = p->d.next; } while (p); return ngx_palloc_block(pool, size); } static void * ngx_palloc_block(ngx_pool_t *pool, size_t size) { u_char *m; size_t psize; ngx_pool_t *p, *new; psize = (size_t) (pool->d.end - (u_char *) pool); m = ngx_memalign(NGX_POOL_ALIGNMENT, psize, pool->log); if (m == NULL) { return NULL; } new = (ngx_pool_t *) m; new->d.end = m + psize; new->d.next = NULL; new->d.failed = 0; m += sizeof(ngx_pool_data_t); m = ngx_align_ptr(m, NGX_ALIGNMENT); new->d.last = m + size; for (p = pool->current; p->d.next; p = p->d.next) { if (p->d.failed++ > 4) { pool->current = p->d.next; } } p->d.next = new; return m; } static void * ngx_palloc_large(ngx_pool_t *pool, size_t size) { void *p; ngx_uint_t n; ngx_pool_large_t *large; p = ngx_alloc(size, pool->log); if (p == NULL) { return NULL; } n = 0; for (large = pool->large; large; large = large->next) { if (large->alloc == NULL) { large->alloc = p; return p; } if (n++ > 3) { break; } } large = ngx_palloc_small(pool, sizeof(ngx_pool_large_t), 1); if (large == NULL) { ngx_free(p); return NULL; } large->alloc = p; large->next = pool->large; pool->large = large; return p; } void * ngx_pmemalign(ngx_pool_t *pool, size_t size, size_t alignment) { void *p; ngx_pool_large_t *large; p = ngx_memalign(alignment, size, pool->log); if (p == NULL) { return NULL; } large = ngx_palloc_small(pool, sizeof(ngx_pool_large_t), 1); if (large == NULL) { ngx_free(p); return NULL; } large->alloc = p; large->next = pool->large; pool->large = large; return p; } ngx_int_t ngx_pfree(ngx_pool_t *pool, void *p) { ngx_pool_large_t *l; for (l = pool->large; l; l = l->next) { if (p == l->alloc) { ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, pool->log, 0, "free: %p", l->alloc); ngx_free(l->alloc); l->alloc = NULL; return NGX_OK; } } return NGX_DECLINED; } void * ngx_pcalloc(ngx_pool_t *pool, size_t size) { void *p; p = ngx_palloc(pool, size); if (p) { ngx_memzero(p, size); } return p; } ngx_pool_cleanup_t * ngx_pool_cleanup_add(ngx_pool_t *p, size_t size) { ngx_pool_cleanup_t *c; c = ngx_palloc(p, sizeof(ngx_pool_cleanup_t)); if (c == NULL) { return NULL; } if (size) { c->data = ngx_palloc(p, size); if (c->data == NULL) { return NULL; } } else { c->data = NULL; } c->handler = NULL; c->next = p->cleanup; p->cleanup = c; ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, p->log, 0, "add cleanup: %p", c); return c; } void ngx_pool_run_cleanup_file(ngx_pool_t *p, ngx_fd_t fd) { ngx_pool_cleanup_t *c; ngx_pool_cleanup_file_t *cf; for (c = p->cleanup; c; c = c->next) { if (c->handler == ngx_pool_cleanup_file) { cf = c->data; if (cf->fd == fd) { c->handler(cf); c->handler = NULL; return; } } } } void ngx_pool_cleanup_file(void *data) { ngx_pool_cleanup_file_t *c = data; ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, c->log, 0, "file cleanup: fd:%d", c->fd); if (ngx_close_file(c->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, ngx_close_file_n " \"%s\" failed", c->name); } } void ngx_pool_delete_file(void *data) { ngx_pool_cleanup_file_t *c = data; ngx_err_t err; ngx_log_debug2(NGX_LOG_DEBUG_ALLOC, c->log, 0, "file cleanup: fd:%d %s", c->fd, c->name); if (ngx_delete_file(c->name) == NGX_FILE_ERROR) { err = ngx_errno; if (err != NGX_ENOENT) { ngx_log_error(NGX_LOG_CRIT, c->log, err, ngx_delete_file_n " \"%s\" failed", c->name); } } if (ngx_close_file(c->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, ngx_close_file_n " \"%s\" failed", c->name); } } #if 0 static void * ngx_get_cached_block(size_t size) { void *p; ngx_cached_block_slot_t *slot; if (ngx_cycle->cache == NULL) { return NULL; } slot = &ngx_cycle->cache[(size + ngx_pagesize - 1) / ngx_pagesize]; slot->tries++; if (slot->number) { p = slot->block; slot->block = slot->block->next; slot->number--; return p; } return NULL; } #endif