From: Ruslan Ermilov <ru@nginx.com> Date: Tue, 26 Jan 2016 16:46:38 +0300 Subject: Resolver: fixed CNAME processing for several requests. When several requests were waiting for a response, then after getting a CNAME response only the last request was properly processed, while others were left waiting. --- src/core/ngx_resolver.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/src/core/ngx_resolver.c b/src/core/ngx_resolver.c index 8ebef6f..3c01584 100644 --- a/src/core/ngx_resolver.c +++ b/src/core/ngx_resolver.c @@ -468,7 +468,7 @@ ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx) ngx_int_t rc; ngx_uint_t naddrs; ngx_addr_t *addrs; - ngx_resolver_ctx_t *next; + ngx_resolver_ctx_t *next, *last; ngx_resolver_node_t *rn; ngx_strlow(ctx->name.data, ctx->name.data, ctx->name.len); @@ -479,6 +479,9 @@ ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx) if (rn) { + /* ctx can be a list after NGX_RESOLVE_CNAME */ + for (last = ctx; last->next; last = last->next); + if (rn->valid >= ngx_time()) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached"); @@ -506,7 +509,7 @@ ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx) } } - ctx->next = rn->waiting; + last->next = rn->waiting; rn->waiting = NULL; /* unlock name mutex */ @@ -552,7 +555,7 @@ ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx) return ngx_resolve_name_locked(r, ctx); } - ctx->next = rn->waiting; + last->next = rn->waiting; rn->waiting = NULL; /* unlock name mutex */ @@ -585,7 +588,7 @@ ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx) ngx_add_timer(ctx->event, ctx->timeout); } - ctx->next = rn->waiting; + last->next = rn->waiting; rn->waiting = ctx; ctx->state = NGX_AGAIN; @@ -656,8 +659,14 @@ ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx) ngx_resolver_free(r, rn->name); ngx_resolver_free(r, rn); - ctx->state = NGX_RESOLVE_NXDOMAIN; - ctx->handler(ctx); + do { + ctx->state = NGX_RESOLVE_NXDOMAIN; + next = ctx->next; + + ctx->handler(ctx); + + ctx = next; + } while (ctx); return NGX_OK; }