加密:qcom-rng - 确保生成缓冲区完全填满 (CVE-2022-48629)
CVE编号
CVE-2022-48629利用情况
暂无补丁情况
N/A披露时间
2024-03-05漏洞描述
In the Linux kernel, the following vulnerability has been resolved: crypto: qcom-rng - ensure buffer for generate is completely filled The generate function in struct rng_alg expects that the destination buffer is completely filled if the function returns 0. qcom_rng_read() can run into a situation where the buffer is partially filled with randomness and the remaining part of the buffer is zeroed since qcom_rng_generate() doesn't check the return value. This issue can be reproduced by running the following from libkcapi: kcapi-rng -b 9000000 > OUTFILE The generated OUTFILE will have three huge sections that contain all zeros, and this is caused by the code where the test 'val & PRNG_STATUS_DATA_AVAIL' fails. Let's fix this issue by ensuring that qcom_rng_read() always returns with a full buffer if the function returns success. Let's also have qcom_rng_generate() return the correct value. Here's some statistics from the ent project (https://www.fourmilab.ch/random/) that shows information about the quality of the generated numbers: $ ent -c qcom-random-before Value Char Occurrences Fraction 0 606748 0.067416 133104 0.003678 233001 0.003667 ... 253 ?32883 0.003654 254 ?33035 0.003671 255 ?33239 0.003693 Total: 9000000 1.000000 Entropy = 7.811590 bits per byte. Optimum compression would reduce the size of this 9000000 byte file by 2 percent. Chi square distribution for 9000000 samples is 9329962.81, and randomly would exceed this value less than 0.01 percent of the times. Arithmetic mean value of data bytes is 119.3731 (127.5 = random). Monte Carlo value for Pi is 3.197293333 (error 1.77 percent). Serial correlation coefficient is 0.159130 (totally uncorrelated = 0.0). Without this patch, the results of the chi-square test is 0.01%, and the numbers are certainly not random according to ent's project page. The results improve with this patch: $ ent -c qcom-random-after Value Char Occurrences Fraction 035432 0.003937 135127 0.003903 235424 0.003936 ... 253 ?35201 0.003911 254 ?34835 0.003871 255 ?35368 0.003930 Total: 9000000 1.000000 Entropy = 7.999979 bits per byte. Optimum compression would reduce the size of this 9000000 byte file by 0 percent. Chi square distribution for 9000000 samples is 258.77, and randomly would exceed this value 42.24 percent of the times. Arithmetic mean value of data bytes is 127.5006 (127.5 = random). Monte Carlo value for Pi is 3.141277333 (error 0.01 percent). Serial correlation coefficient is 0.000468 (totally uncorrelated = 0.0). This change was tested on a Nexus 5 phone (msm8974 SoC).解决建议
建议您更新当前系统或软件至最新版,完成漏洞的修复。受影响软件情况
# | 类型 | 厂商 | 产品 | 版本 | 影响面 | ||||
1 | |||||||||
---|---|---|---|---|---|---|---|---|---|
运行在以下环境 | |||||||||
系统 | debian_10 | linux | * | Up to (excluding) 4.19.249-1 | |||||
运行在以下环境 | |||||||||
系统 | debian_11 | linux | * | Up to (excluding) 5.10.113-1 | |||||
运行在以下环境 | |||||||||
系统 | debian_12 | linux | * | Up to (excluding) 5.16.18-1 |
- 攻击路径 N/A
- 攻击复杂度 N/A
- 权限要求 N/A
- 影响范围 N/A
- 用户交互 N/A
- 可用性 N/A
- 保密性 N/A
- 完整性 N/A
CWE-ID | 漏洞类型 |
Exp相关链接

版权声明
本站原创文章转载请注明文章出处及链接,谢谢合作!
评论