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view src/os/unix/ngx_sunpro_sparc64.il @ 7386:9200b41db765 stable-1.14
HTTP/2: limit the number of idle state switches.
An attack that continuously switches HTTP/2 connection between
idle and active states can result in excessive CPU usage.
This is because when a connection switches to the idle state,
all of its memory pool caches are freed.
This change limits the maximum allowed number of idle state
switches to 10 * http2_max_requests (i.e., 10000 by default).
This limits possible CPU usage in one connection, and also
imposes a limit on the maximum lifetime of a connection.
Initially reported by Gal Goldshtein from F5 Networks.
author | Ruslan Ermilov <ru@nginx.com> |
---|---|
date | Tue, 06 Nov 2018 16:29:49 +0300 |
parents | d620f497c50f |
children |
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/ / Copyright (C) Igor Sysoev / Copyright (C) Nginx, Inc. / / "casa [%o2] 0x80, %o1, %o0" and / "casxa [%o2] 0x80, %o1, %o0" do the following: / / if ([%o2] == %o1) { / swap(%o0, [%o2]); / } else { / %o0 = [%o2]; / } / ngx_atomic_uint_t ngx_casa(ngx_atomic_uint_t set, ngx_atomic_uint_t old, / ngx_atomic_t *lock); / / the arguments are passed in the %o0, %o1, %o2 / the result is returned in the %o0 .inline ngx_casa,0 casa [%o2] 0x80, %o1, %o0 .end / ngx_atomic_uint_t ngx_casxa(ngx_atomic_uint_t set, ngx_atomic_uint_t old, / ngx_atomic_t *lock); / / the arguments are passed in the %o0, %o1, %o2 / the result is returned in the %o0 .inline ngx_casxa,0 casxa [%o2] 0x80, %o1, %o0 .end