Mercurial > hg > nginx-quic
view src/http/ngx_http_busy_lock.c @ 4664:356c91151658 stable-1.2
Merge of r4618: rewrite escaping fix (ticket #162).
The following code resulted in incorrect escaping of uri and possible
segfault:
location / {
rewrite ^(.*) $1?c=$1;
return 200 "$uri";
}
If there were arguments in a rewrite's replacement string, and length was
actually calculated (due to duplicate captures as in the example above,
or variables present), the is_args flag was set and incorrectly copied
after length calculation. This resulted in escaping applied to the uri part
of the replacement, resulting in incorrect escaping. Additionally, buffer
was allocated without escaping expected, thus this also resulted in buffer
overrun and possible segfault.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 04 Jun 2012 11:07:19 +0000 |
parents | 14411ee4d89f |
children |
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line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> static int ngx_http_busy_lock_look_cacheable(ngx_http_busy_lock_t *bl, ngx_http_busy_lock_ctx_t *bc, int lock); int ngx_http_busy_lock(ngx_http_busy_lock_t *bl, ngx_http_busy_lock_ctx_t *bc) { if (bl->busy < bl->max_busy) { bl->busy++; if (bc->time) { bc->time = 0; bl->waiting--; } return NGX_OK; } if (bc->time) { if (bc->time < bl->timeout) { ngx_add_timer(bc->event, 1000); return NGX_AGAIN; } bl->waiting--; return NGX_DONE; } if (bl->timeout == 0) { return NGX_DONE; } if (bl->waiting < bl->max_waiting) { bl->waiting++; #if 0 ngx_add_timer(bc->event, 1000); bc->event->event_handler = bc->event_handler; #endif /* TODO: ngx_handle_level_read_event() */ return NGX_AGAIN; } return NGX_ERROR; } int ngx_http_busy_lock_cacheable(ngx_http_busy_lock_t *bl, ngx_http_busy_lock_ctx_t *bc, int lock) { int rc; rc = ngx_http_busy_lock_look_cacheable(bl, bc, lock); ngx_log_debug3(NGX_LOG_DEBUG_HTTP, bc->event->log, 0, "http busylock: %d w:%d mw::%d", rc, bl->waiting, bl->max_waiting); if (rc == NGX_OK) { /* no the same request, there's free slot */ return NGX_OK; } if (rc == NGX_ERROR && !lock) { /* no the same request, no free slot */ return NGX_OK; } /* rc == NGX_AGAIN: the same request */ if (bc->time) { if (bc->time < bl->timeout) { ngx_add_timer(bc->event, 1000); return NGX_AGAIN; } bl->waiting--; return NGX_DONE; } if (bl->timeout == 0) { return NGX_DONE; } if (bl->waiting < bl->max_waiting) { #if 0 bl->waiting++; ngx_add_timer(bc->event, 1000); bc->event->event_handler = bc->event_handler; #endif /* TODO: ngx_handle_level_read_event() */ return NGX_AGAIN; } return NGX_ERROR; } void ngx_http_busy_unlock(ngx_http_busy_lock_t *bl, ngx_http_busy_lock_ctx_t *bc) { if (bl == NULL) { return; } if (bl->md5) { bl->md5_mask[bc->slot / 8] &= ~(1 << (bc->slot & 7)); bl->cacheable--; } bl->busy--; } static int ngx_http_busy_lock_look_cacheable(ngx_http_busy_lock_t *bl, ngx_http_busy_lock_ctx_t *bc, int lock) { int i, b, cacheable, free; u_int mask; b = 0; cacheable = 0; free = -1; #if (NGX_SUPPRESS_WARN) mask = 0; #endif for (i = 0; i < bl->max_busy; i++) { if ((b & 7) == 0) { mask = bl->md5_mask[i / 8]; } if (mask & 1) { if (ngx_memcmp(&bl->md5[i * 16], bc->md5, 16) == 0) { return NGX_AGAIN; } cacheable++; } else if (free == -1) { free = i; } #if 1 if (cacheable == bl->cacheable) { if (free == -1 && cacheable < bl->max_busy) { free = i + 1; } break; } #endif mask >>= 1; b++; } if (free == -1) { return NGX_ERROR; } if (lock) { if (bl->busy == bl->max_busy) { return NGX_ERROR; } ngx_memcpy(&bl->md5[free * 16], bc->md5, 16); bl->md5_mask[free / 8] |= 1 << (free & 7); bc->slot = free; bl->cacheable++; bl->busy++; } return NGX_OK; } char *ngx_http_set_busy_lock_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { char *p = conf; ngx_uint_t i, dup, invalid; ngx_str_t *value, line; ngx_http_busy_lock_t *bl, **blp; blp = (ngx_http_busy_lock_t **) (p + cmd->offset); if (*blp) { return "is duplicate"; } /* ngx_calloc_shared() */ bl = ngx_pcalloc(cf->pool, sizeof(ngx_http_busy_lock_t)); if (bl == NULL) { return NGX_CONF_ERROR; } *blp = bl; /* ngx_calloc_shared() */ bl->mutex = ngx_pcalloc(cf->pool, sizeof(ngx_event_mutex_t)); if (bl->mutex == NULL) { return NGX_CONF_ERROR; } dup = 0; invalid = 0; value = cf->args->elts; for (i = 1; i < cf->args->nelts; i++) { if (value[i].data[1] != '=') { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid value \"%s\"", value[i].data); return NGX_CONF_ERROR; } switch (value[i].data[0]) { case 'b': if (bl->max_busy) { dup = 1; break; } bl->max_busy = ngx_atoi(value[i].data + 2, value[i].len - 2); if (bl->max_busy == NGX_ERROR) { invalid = 1; break; } continue; case 'w': if (bl->max_waiting) { dup = 1; break; } bl->max_waiting = ngx_atoi(value[i].data + 2, value[i].len - 2); if (bl->max_waiting == NGX_ERROR) { invalid = 1; break; } continue; case 't': if (bl->timeout) { dup = 1; break; } line.len = value[i].len - 2; line.data = value[i].data + 2; bl->timeout = ngx_parse_time(&line, 1); if (bl->timeout == (time_t) NGX_ERROR) { invalid = 1; break; } continue; default: invalid = 1; } if (dup) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate value \"%s\"", value[i].data); return NGX_CONF_ERROR; } if (invalid) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid value \"%s\"", value[i].data); return NGX_CONF_ERROR; } } if (bl->timeout == 0 && bl->max_waiting) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "busy lock waiting is useless with zero timeout, ignoring"); } return NGX_CONF_OK; }