CVE-2025-39756

一、漏洞信息
 漏洞编号：[CVE-2025-39756](https://nvd.nist.gov/vuln/detail/CVE-2025-39756)
 漏洞归属组件：[kernel](https://gitee.com/src-openeuler/kernel)
 漏洞归属的版本：4.19.140,4.19.194,4.19.90,5.10.0,6.1.19,6.4.0,6.6.0
 CVSS V3.0分值：
  BaseScore：N/A None
  Vector：CVSS：3.0/
 漏洞简述：
  In the Linux kernel, the following vulnerability has been resolved:fs: Prevent file descriptor table allocations exceeding INT_MAXWhen sysctl_nr_open is set to a very high value (for example, 1073741816as set by systemd), processes attempting to use file descriptors nearthe limit can trigger massive memory allocation attempts that exceedINT_MAX, resulting in a WARNING in mm/slub.c:  WARNING: CPU: 0 PID: 44 at mm/slub.c:5027 __kvmalloc_node_noprof+0x21a/0x288This happens because kvmalloc_array() and kvmalloc() check if therequested size exceeds INT_MAX and emit a warning when the allocation isnot flagged with __GFP_NOWARN.Specifically, when nr_open is set to 1073741816 (0x3ffffff8) and aprocess calls dup2(oldfd, 1073741880), the kernel attempts to allocate:- File descriptor array: 1073741880 * 8 bytes = 8,589,935,040 bytes- Multiple bitmaps: ~400MB- Total allocation size: > 8GB (exceeding INT_MAX = 2,147,483,647)Reproducer:1. Set /proc/sys/fs/nr_open to 1073741816:   # echo 1073741816 > /proc/sys/fs/nr_open2. Run a program that uses a high file descriptor:   #include <unistd.h>   #include <sys/resource.h>   int main() {       struct rlimit rlim = {1073741824, 1073741824};       setrlimit(RLIMIT_NOFILE, &rlim);       dup2(2, 1073741880);  // Triggers the warning       return 0;   }3. Observe WARNING in dmesg at mm/slub.c:5027systemd commit a8b627a introduced automatic bumping of fs.nr_open to themaximum possible value. The rationale was that systems with memorycontrol groups (memcg) no longer need separate file descriptor limitssince memory is properly accounted. However, this change overlookedthat:1. The kernel s allocation functions still enforce INT_MAX as a maximum   size regardless of memcg accounting2. Programs and tests that legitimately test file descriptor limits can   inadvertently trigger massive allocations3. The resulting allocations (>8GB) are impractical and will always failsystemd s algorithm starts with INT_MAX and keeps halving the valueuntil the kernel accepts it. On most systems, this results in nr_openbeing set to 1073741816 (0x3ffffff8), which is just under 1GB of filedescriptors.While processes rarely use file descriptors near this limit in normaloperation, certain selftests (liketools/testing/selftests/core/unshare_test.c) and programs that test filedescriptor limits can trigger this issue.Fix this by adding a check in alloc_fdtable() to ensure the requestedallocation size does not exceed INT_MAX. This causes the operation tofail with -EMFILE instead of triggering a kernel warning and avoids theimpractical >8GB memory allocation request.
 漏洞公开时间：2025-09-12 01:15:39
 漏洞创建时间：2025-09-12 02:03:48
 漏洞详情参考链接：
  https://nvd.nist.gov/vuln/detail/CVE-2025-39756
<details>
<summary>更多参考(点击展开)</summary>

| 参考来源 | 参考链接 | 来源链接 |
| ------- | -------- | -------- |
|  | https://git.kernel.org/stable/c/b4159c5a90c03f8acd3de345a7f5fc63b0909818 |  |
|  | https://git.kernel.org/stable/c/f95638a8f22eba307dceddf5aef9ae2326bbcf98 |  |
|  | https://git.kernel.org/stable/c/749528086620f8012b83ae032a80f6ffa80c45cd |  |
|  | https://git.kernel.org/stable/c/628fc28f42d979f36dbf75a6129ac7730e30c04e |  |
|  | https://git.kernel.org/stable/c/237e416eb62101f21b28c9e6e564d10efe1ecc6f |  |
|  | https://git.kernel.org/stable/c/d4f9351243c17865a8cdbe6b3ccd09d0b13a7bcc |  |
|  | https://git.kernel.org/stable/c/9f61fa6a2a89a610120bc4e5d24379c667314b5c |  |
|  | https://git.kernel.org/stable/c/dfd1f4ea98c3bd3a03d12169b5b2daa1f0a3e4ae |  |
|  | https://git.kernel.org/stable/c/04a2c4b4511d186b0fce685da21085a5d4acd370 |  |
|  | https://lore.kernel.org/linux-cve-announce/2025091144-CVE-2025-39756-6e90@gregkh/T/#u |  |
|  | https://security-tracker.debian.org/tracker/CVE-2025-39756 |  |
|  | https://www.cve.org/CVERecord?id=CVE-2025-39756 |  |
|  | https://nvd.nist.gov/vuln/detail/CVE-2025-39756 |  |
|  | https://lore.kernel.org/linux-cve-announce/2025091144-CVE-2025-39756-6e90@gregkh/T |  |
|  | https://bugzilla.redhat.com/show_bug.cgi?id=2394600 |  |
|  | https://docs.bell-sw.com/security/cves/CVE-2025-39756 |  |
|  | https://ubuntu.com/security/CVE-2025-39756 |  |
|  | https://www.cve.org/CVERecord?id=CVE-2025-39756 |  |
|  | https://git.kernel.org/linus/04a2c4b4511d186b0fce685da21085a5d4acd370 |  |
|  | https://git.kernel.org/stable/c/04a2c4b4511d186b0fce685da21085a5d4acd370 |  |
|  | https://git.kernel.org/stable/c/237e416eb62101f21b28c9e6e564d10efe1ecc6f |  |
|  | https://git.kernel.org/stable/c/628fc28f42d979f36dbf75a6129ac7730e30c04e |  |
|  | https://git.kernel.org/stable/c/749528086620f8012b83ae032a80f6ffa80c45cd |  |
|  | https://git.kernel.org/stable/c/9f61fa6a2a89a610120bc4e5d24379c667314b5c |  |
|  | https://git.kernel.org/stable/c/b4159c5a90c03f8acd3de345a7f5fc63b0909818 |  |
|  | https://git.kernel.org/stable/c/d4f9351243c17865a8cdbe6b3ccd09d0b13a7bcc |  |
|  | https://git.kernel.org/stable/c/dfd1f4ea98c3bd3a03d12169b5b2daa1f0a3e4ae |  |
|  | https://git.kernel.org/stable/c/f95638a8f22eba307dceddf5aef9ae2326bbcf98 |  |
|  | http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-39756 |  |
|  | https://git.kernel.org/stable/c/04a2c4b4511d186b0fce685da21085a5d4acd370 |  |
|  | https://git.kernel.org/stable/c/237e416eb62101f21b28c9e6e564d10efe1ecc6f |  |
|  | https://git.kernel.org/stable/c/628fc28f42d979f36dbf75a6129ac7730e30c04e |  |
|  | https://git.kernel.org/stable/c/749528086620f8012b83ae032a80f6ffa80c45cd |  |
|  | https://git.kernel.org/stable/c/9f61fa6a2a89a610120bc4e5d24379c667314b5c |  |
|  | https://git.kernel.org/stable/c/b4159c5a90c03f8acd3de345a7f5fc63b0909818 |  |
|  | https://git.kernel.org/stable/c/d4f9351243c17865a8cdbe6b3ccd09d0b13a7bcc |  |
|  | https://git.kernel.org/stable/c/dfd1f4ea98c3bd3a03d12169b5b2daa1f0a3e4ae |  |
|  | https://git.kernel.org/stable/c/f95638a8f22eba307dceddf5aef9ae2326bbcf98 |  |

</details>

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:
  七彩瞬析开源风险感知平台
 漏洞补丁信息：
  <details>
<summary>详情(点击展开)</summary>

| 影响的包 | 修复版本 | 修复补丁 | 问题引入补丁 | 来源  |
| ------- | -------- | ------- | -------- | --------- |
| gregkh/linux |  | https://github.com/gregkh/linux/commit/04a2c4b4511d186b0fce685da21085a5d4acd370.patch |  | ljqc |
|  |  | https://git.kernel.org/stable/c/b4159c5a90c03f8acd3de345a7f5fc63b0909818 |  | cvelistv5 |
|  |  | https://git.kernel.org/stable/c/f95638a8f22eba307dceddf5aef9ae2326bbcf98 |  | cvelistv5 |
|  |  | https://git.kernel.org/stable/c/749528086620f8012b83ae032a80f6ffa80c45cd |  | cvelistv5 |
|  |  | https://git.kernel.org/stable/c/628fc28f42d979f36dbf75a6129ac7730e30c04e |  | cvelistv5 |
|  |  | https://git.kernel.org/stable/c/237e416eb62101f21b28c9e6e564d10efe1ecc6f |  | cvelistv5 |
|  |  | https://git.kernel.org/stable/c/d4f9351243c17865a8cdbe6b3ccd09d0b13a7bcc |  | cvelistv5 |
|  |  | https://git.kernel.org/stable/c/9f61fa6a2a89a610120bc4e5d24379c667314b5c |  | cvelistv5 |
|  |  | https://git.kernel.org/stable/c/dfd1f4ea98c3bd3a03d12169b5b2daa1f0a3e4ae |  | cvelistv5 |
|  |  | https://git.kernel.org/stable/c/04a2c4b4511d186b0fce685da21085a5d4acd370 |  | cvelistv5 |
|  |  | https://git.kernel.org/linus/04a2c4b4511d186b0fce685da21085a5d4acd370 |  | osv |
|  |  | https://git.kernel.org/stable/c/04a2c4b4511d186b0fce685da21085a5d4acd370 |  | osv |
|  |  | https://git.kernel.org/stable/c/237e416eb62101f21b28c9e6e564d10efe1ecc6f |  | osv |
|  |  | https://git.kernel.org/stable/c/628fc28f42d979f36dbf75a6129ac7730e30c04e |  | osv |
|  |  | https://git.kernel.org/stable/c/749528086620f8012b83ae032a80f6ffa80c45cd |  | osv |
|  |  | https://git.kernel.org/stable/c/9f61fa6a2a89a610120bc4e5d24379c667314b5c |  | osv |
|  |  | https://git.kernel.org/stable/c/b4159c5a90c03f8acd3de345a7f5fc63b0909818 |  | osv |
|  |  | https://git.kernel.org/stable/c/d4f9351243c17865a8cdbe6b3ccd09d0b13a7bcc |  | osv |
|  |  | https://git.kernel.org/stable/c/dfd1f4ea98c3bd3a03d12169b5b2daa1f0a3e4ae |  | osv |
|  |  | https://git.kernel.org/stable/c/f95638a8f22eba307dceddf5aef9ae2326bbcf98 |  | osv |
|  |  | https://git.kernel.org/stable/c/04a2c4b4511d186b0fce685da21085a5d4acd370 |  | snyk |
|  |  | https://git.kernel.org/stable/c/237e416eb62101f21b28c9e6e564d10efe1ecc6f |  | snyk |
|  |  | https://git.kernel.org/stable/c/628fc28f42d979f36dbf75a6129ac7730e30c04e |  | snyk |
|  |  | https://git.kernel.org/stable/c/749528086620f8012b83ae032a80f6ffa80c45cd |  | snyk |
|  |  | https://git.kernel.org/stable/c/9f61fa6a2a89a610120bc4e5d24379c667314b5c |  | snyk |
|  |  | https://git.kernel.org/stable/c/b4159c5a90c03f8acd3de345a7f5fc63b0909818 |  | snyk |
|  |  | https://git.kernel.org/stable/c/d4f9351243c17865a8cdbe6b3ccd09d0b13a7bcc |  | snyk |
|  |  | https://git.kernel.org/stable/c/dfd1f4ea98c3bd3a03d12169b5b2daa1f0a3e4ae |  | snyk |
|  |  | https://git.kernel.org/stable/c/f95638a8f22eba307dceddf5aef9ae2326bbcf98 |  | snyk |

</details>

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:fs: Prevent file descriptor table allocations exceeding INT_MAXWhen sysctl_nr_open is set to a very high value (for example, 1073741816as set by systemd), processes attempting to use file descriptors nearthe limit can trigger massive memory allocation attempts that exceedINT_MAX, resulting in a WARNING in mm/slub.c:  WARNING: CPU: 0 PID: 44 at mm/slub.c:5027 __kvmalloc_node_noprof+0x21a/0x288This happens because kvmalloc_array() and kvmalloc() check if therequested size exceeds INT_MAX and emit a warning when the allocation isnot flagged with __GFP_NOWARN.Specifically, when nr_open is set to 1073741816 (0x3ffffff8) and aprocess calls dup2(oldfd, 1073741880), the kernel attempts to allocate:- File descriptor array: 1073741880 * 8 bytes = 8,589,935,040 bytes- Multiple bitmaps: ~400MB- Total allocation size: &gt; 8GB (exceeding INT_MAX = 2,147,483,647)Reproducer:1. Set /proc/sys/fs/nr_open to 1073741816:   # echo 1073741816 &gt; /proc/sys/fs/nr_open2. Run a program that uses a high file descriptor:   #include &lt;unistd.h&gt;   #include &lt;sys/resource.h&gt;   int main() {       struct rlimit rlim = {1073741824, 1073741824};       setrlimit(RLIMIT_NOFILE, &amp;rlim);       dup2(2, 1073741880);  // Triggers the warning       return 0;   }3. Observe WARNING in dmesg at mm/slub.c:5027systemd commit a8b627a introduced automatic bumping of fs.nr_open to themaximum possible value. The rationale was that systems with memorycontrol groups (memcg) no longer need separate file descriptor limitssince memory is properly accounted. However, this change overlookedthat:1. The kernel s allocation functions still enforce INT_MAX as a maximum   size regardless of memcg accounting2. Programs and tests that legitimately test file descriptor limits can   inadvertently trigger massive allocations3. The resulting allocations (&gt;8GB) are impractical and will always failsystemd s algorithm starts with INT_MAX and keeps halving the valueuntil the kernel accepts it. On most systems, this results in nr_openbeing set to 1073741816 (0x3ffffff8), which is just under 1GB of filedescriptors.While processes rarely use file descriptors near this limit in normaloperation, certain selftests (liketools/testing/selftests/core/unshare_test.c) and programs that test filedescriptor limits can trigger this issue.Fix this by adding a check in alloc_fdtable() to ensure the requestedallocation size does not exceed INT_MAX. This causes the operation tofail with -EMFILE instead of triggering a kernel warning and avoids theimpractical &gt;8GB memory allocation request.The Linux kernel CVE team has assigned CVE-2025-39756 to this issue.
 openEuler评分：
  3.9
 Vector：CVSS：3.0/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L
 受影响版本排查(受影响/不受影响)：
  1.openEuler-20.03-LTS-SP4(4.19.90):受影响
2.openEuler-22.03-LTS-SP3(5.10.0):受影响
3.openEuler-22.03-LTS-SP4(5.10.0):受影响
4.openEuler-24.03-LTS(6.6.0):受影响
5.openEuler-24.03-LTS-SP1(6.6.0):受影响
6.openEuler-24.03-LTS-SP2(6.6.0):受影响
7.master(6.12.33):不受影响
8.openEuler-24.03-LTS-Next(6.6.0):不受影响

修复是否涉及abi变化(是/否)：
  1.master(6.12.33):否
2.openEuler-20.03-LTS-SP4(4.19.90):否
3.openEuler-22.03-LTS-SP3(5.10.0):否
4.openEuler-22.03-LTS-SP4(5.10.0):否
5.openEuler-24.03-LTS(6.6.0):否
6.openEuler-24.03-LTS-Next(6.6.0):否
7.openEuler-24.03-LTS-SP1(6.6.0):否
8.openEuler-24.03-LTS-SP2(6.6.0):否

原因说明：
  1.openEuler-22.03-LTS-SP3(5.10.0):正常修复
2.openEuler-22.03-LTS-SP4(5.10.0):正常修复
3.openEuler-24.03-LTS(6.6.0):正常修复
4.openEuler-24.03-LTS-SP1(6.6.0):正常修复
5.openEuler-24.03-LTS-SP2(6.6.0):正常修复
6.openEuler-20.03-LTS-SP4(4.19.90):不修复-超出修复范围
7.master(6.12.33):不受影响-漏洞代码不能被攻击者触发
8.openEuler-24.03-LTS-Next(6.6.0):不受影响-漏洞代码不能被攻击者触发

src-openEuler/kernel

内容风险标识

评论 (7)

src-openEuler/kernel .gitee-modal { width: 500px !important; }

内容风险标识

CVE-2025-39756

评论 (7)

搜索帮助

src-openEuler/kernel