Mercurial > hg > nginx
view src/core/ngx_cpuinfo.c @ 7690:8253424d1aff
Added size check to ngx_http_alloc_large_header_buffer().
This ensures that copying won't write more than the buffer size
even if the buffer comes from hc->free and it is smaller than the large
client header buffer size in the virtual host configuration. This might
happen if size of large client header buffers is different in name-based
virtual hosts, similarly to the problem with number of buffers fixed
in 6926:e662cbf1b932.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 06 Aug 2020 05:02:22 +0300 |
parents | d620f497c50f |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #if (( __i386__ || __amd64__ ) && ( __GNUC__ || __INTEL_COMPILER )) static ngx_inline void ngx_cpuid(uint32_t i, uint32_t *buf); #if ( __i386__ ) static ngx_inline void ngx_cpuid(uint32_t i, uint32_t *buf) { /* * we could not use %ebx as output parameter if gcc builds PIC, * and we could not save %ebx on stack, because %esp is used, * when the -fomit-frame-pointer optimization is specified. */ __asm__ ( " mov %%ebx, %%esi; " " cpuid; " " mov %%eax, (%1); " " mov %%ebx, 4(%1); " " mov %%edx, 8(%1); " " mov %%ecx, 12(%1); " " mov %%esi, %%ebx; " : : "a" (i), "D" (buf) : "ecx", "edx", "esi", "memory" ); } #else /* __amd64__ */ static ngx_inline void ngx_cpuid(uint32_t i, uint32_t *buf) { uint32_t eax, ebx, ecx, edx; __asm__ ( "cpuid" : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (i) ); buf[0] = eax; buf[1] = ebx; buf[2] = edx; buf[3] = ecx; } #endif /* auto detect the L2 cache line size of modern and widespread CPUs */ void ngx_cpuinfo(void) { u_char *vendor; uint32_t vbuf[5], cpu[4], model; vbuf[0] = 0; vbuf[1] = 0; vbuf[2] = 0; vbuf[3] = 0; vbuf[4] = 0; ngx_cpuid(0, vbuf); vendor = (u_char *) &vbuf[1]; if (vbuf[0] == 0) { return; } ngx_cpuid(1, cpu); if (ngx_strcmp(vendor, "GenuineIntel") == 0) { switch ((cpu[0] & 0xf00) >> 8) { /* Pentium */ case 5: ngx_cacheline_size = 32; break; /* Pentium Pro, II, III */ case 6: ngx_cacheline_size = 32; model = ((cpu[0] & 0xf0000) >> 8) | (cpu[0] & 0xf0); if (model >= 0xd0) { /* Intel Core, Core 2, Atom */ ngx_cacheline_size = 64; } break; /* * Pentium 4, although its cache line size is 64 bytes, * it prefetches up to two cache lines during memory read */ case 15: ngx_cacheline_size = 128; break; } } else if (ngx_strcmp(vendor, "AuthenticAMD") == 0) { ngx_cacheline_size = 64; } } #else void ngx_cpuinfo(void) { } #endif