一、漏洞信息
漏洞编号：CVE-2024-26712
漏洞归属组件：kernel
漏洞归属的版本：4.19.140,4.19.194,4.19.90,5.10.0,6.1.0,6.1.14,6.1.19,6.1.5,6.1.6,6.1.8,6.4.0
CVSS V2.0分值：
BaseScore：0.0 Low
Vector：CVSS：2.0/
漏洞简述：
In the Linux kernel, the following vulnerability has been resolved:powerpc/kasan: Fix addr error caused by page alignmentIn kasan_init_region, when k_start is not page aligned, at the begin offor loop, k_cur = k_start & PAGE_MASK is less than k_start, and thenva = block + k_cur - k_start is less than block, the addr va is invalid,because the memory address space from va to block is not alloced bymemblock_alloc, which will not be reserved by memblock_reserve later, itwill be used by other places.As a result, memory overwriting occurs.for example:int __init __weak kasan_init_region(void start, size_t size){[...] / if say block(dcd97000) k_start(feef7400) k_end(feeff3fe) / block = memblock_alloc(k_end - k_start, PAGE_SIZE); [...] for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) { / at the begin of for loop * block(dcd97000) va(dcd96c00) k_cur(feef7000) k_start(feef7400) * va(dcd96c00) is less than block(dcd97000), va is invalid */ void *va = block + k_cur - k_start; [...] }[...]}Therefore, page alignment is performed on k_start beforememblock_alloc() to ensure the validity of the VA address.
漏洞公开时间：2024-04-03 23:15:53
漏洞创建时间：2024-04-03 23:51:01
漏洞详情参考链接：
https://nvd.nist.gov/vuln/detail/CVE-2024-26712

漏洞分析指导链接：
https://gitee.com/openeuler/cve-manager/blob/master/cve-vulner-manager/doc/md/manual.md
漏洞数据来源:
openBrain开源漏洞感知系统
漏洞补丁信息：

二、漏洞分析结构反馈
影响性分析说明：
In the Linux kernel, the following vulnerability has been resolved:powerpc/kasan: Fix addr error caused by page alignmentIn kasan_init_region, when k_start is not page aligned, at the begin offor loop, k_cur = k_start & PAGE_MASK is less than k_start, and thenva = block + k_cur - k_start is less than block, the addr va is invalid,because the memory address space from va to block is not alloced bymemblock_alloc, which will not be reserved by memblock_reserve later, itwill be used by other places.As a result, memory overwriting occurs.for example:int __init __weak kasan_init_region(void start, size_t size){[...]/ if say block(dcd97000) k_start(feef7400) k_end(feeff3fe) /block = memblock_alloc(k_end - k_start, PAGE_SIZE);[...]for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) {/ at the begin of for loop * block(dcd97000) va(dcd96c00) k_cur(feef7000) k_start(feef7400) * va(dcd96c00) is less than block(dcd97000), va is invalid */void *va = block + k_cur - k_start;[...]}[...]}Therefore, page alignment is performed on k_start beforememblock_alloc() to ensure the validity of the VA address.
openEuler评分：
4.4
Vector：CVSS：2.0/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
受影响版本排查(受影响/不受影响)：
1.openEuler-22.03-LTS(5.10.0):受影响
2.openEuler-22.03-LTS-SP1(5.10.0):受影响
3.openEuler-22.03-LTS-SP2(5.10.0):受影响
4.openEuler-22.03-LTS-SP3(5.10.0):受影响
5.openEuler-20.03-LTS-SP1(4.19.90):不受影响
6.openEuler-20.03-LTS-SP4(4.19.90):不受影响
7.master(6.1.0):不受影响
8.openEuler-22.03-LTS-Next(5.10.0):不受影响
9.openEuler-24.03-LTS:不受影响
10.openEuler-24.03-LTS-Next:不受影响
11.openEuler-22.03-LTS-SP4:不受影响

修复是否涉及abi变化(是/否)：
1.openEuler-20.03-LTS-SP1(4.19.90):否
2.openEuler-20.03-LTS-SP4(4.19.90):否
3.openEuler-22.03-LTS(5.10.0):否
4.openEuler-22.03-LTS-SP1(5.10.0):否
5.openEuler-22.03-LTS-SP2(5.10.0):否
6.openEuler-22.03-LTS-SP3(5.10.0):否
7.master(6.1.0):否
8.openEuler-22.03-LTS-Next(5.10.0):否
9.openEuler-24.03-LTS:否
10.openEuler-24.03-LTS-Next:否