[LZerro]

拉取/合并请求描述：(PR description)

[

为什么提交这份PR (why to submit this PR)

你的解决方案是什么 (what is your solution)

请提供验证的bsp和config (provide the config and bsp)

• BSP:

• .config:

• action:

]

当前拉取/合并请求的状态 Intent for your PR

必须选择一项 Choose one (Mandatory):

• 本拉取/合并请求是一个草稿版本 This PR is for a code-review and is intended to get feedback
• 本拉取/合并请求是一个成熟版本 This PR is mature, and ready to be integrated into the repo

代码质量 Code Quality：

我在这个拉取/合并请求中已经考虑了 As part of this pull request, I've considered the following:

• 已经仔细查看过代码改动的对比 Already check the difference between PR and old code
• 代码风格正确，包括缩进空格，命名及其他风格 Style guide is adhered to, including spacing, naming and other styles
• 没有垃圾代码，代码尽量精简，不包含#if 0代码，不包含已经被注释了的代码 All redundant code is removed and cleaned up
• 所有变更均有原因及合理的，并且不会影响到其他软件组件代码或BSP All modifications are justified and not affect other components or BSP
• 对难懂代码均提供对应的注释 I've commented appropriately where code is tricky
• 代码是高质量的 Code in this PR is of high quality
• 已经使用formatting 等源码格式化工具确保格式符合RT-Thread代码规范 This PR complies with RT-Thread code specification
• 如果是新增bsp, 已经添加ci检查到.github/ALL_BSP_COMPILE.json 详细请参考链接BSP自查

[github-actions]

📌 Code Review Assignment

🏷️ Tag: components

Reviewers: @Maihuanyi

Changed Files (Click to expand)

• components/dfs/Kconfig
• components/dfs/dfs_v1/filesystems/cromfs/dfs_cromfs.c
• components/dfs/dfs_v1/filesystems/elmfat/dfs_elm.c
• components/dfs/dfs_v1/filesystems/nfs/dfs_nfs.c
• components/dfs/dfs_v1/filesystems/skeleton/skeleton.c
• components/dfs/dfs_v1/include/dfs_file.h
• components/dfs/dfs_v1/src/dfs_file.c
• components/dfs/dfs_v1/src/dfs_posix.c
• components/dfs/dfs_v2/filesystems/elmfat/dfs_elm.c
• components/dfs/dfs_v2/filesystems/ramfs/dfs_ramfs.c
• components/dfs/dfs_v2/filesystems/skeleton/skeleton.c
• components/dfs/dfs_v2/include/dfs_file.h
• components/dfs/dfs_v2/src/dfs_file.c
• components/libc/compilers/common/extension/sys/stat.h
• components/libc/compilers/common/extension/sys/types.h

🏷️ Tag: components_libc

Reviewers: @GorrayLi @mysterywolf

Changed Files (Click to expand)

• components/libc/compilers/common/extension/sys/stat.h
• components/libc/compilers/common/extension/sys/types.h

---

📊 Current Review Status (Last Updated: 2026-06-15 18:08 CST)

• ⌛ @GorrayLi Pending Review
• ⌛ @Maihuanyi Pending Review
• ⌛ @mysterywolf Pending Review

---

📝 Review Instructions

1. 维护者可以通过单击此处来刷新审查状态: 🔄 刷新状态
   Maintainers can refresh the review status by clicking here: 🔄 Refresh Status

2. 确认审核通过后评论 LGTM/lgtm
   Comment LGTM/lgtm after confirming approval

3. PR合并前需至少一位维护者确认
   PR must be confirmed by at least one maintainer before merging

ℹ️ 刷新CI状态操作需要具备仓库写入权限。
ℹ️ Refresh CI status operation requires repository Write permission.

[github-actions]

👋 感谢您对 RT-Thread 的贡献！Thank you for your contribution to RT-Thread!

为确保代码符合 RT-Thread 的编码规范，请在你的仓库中执行以下步骤运行代码格式化工作流（如果格式化CI运行失败）。
To ensure your code complies with RT-Thread's coding style, please run the code formatting workflow by following the steps below (If the formatting of CI fails to run).

---

🛠 操作步骤 | Steps

1. 前往 Actions 页面 | Go to the Actions page
   点击进入工作流 → | Click to open workflow →

2. 点击 Run workflow | Click Run workflow

• 设置需排除的文件/目录（目录请以"/"结尾）
  Set files/directories to exclude (directories should end with "/")
• 将目标分支设置为 \ Set the target branch to：LZerro_Fat_Large_File
• 设置PR number为 \ Set the PR number to：11492

3. 等待工作流完成 | Wait for the workflow to complete
   格式化后的代码将自动推送至你的分支。
   The formatted code will be automatically pushed to your branch.

完成后，提交将自动更新至 LZerro_Fat_Large_File 分支，关联的 Pull Request 也会同步更新。
Once completed, commits will be pushed to the LZerro_Fat_Large_File branch automatically, and the related Pull Request will be updated.

如有问题欢迎联系我们，再次感谢您的贡献！💐
If you have any questions, feel free to reach out. Thanks again for your contribution!

[BernardXiong]

Review / 审查

结论 / Conclusion: blocking correctness issue found; please fix the offset arithmetic and add boundary tests before merge.

严重 / Blocking

1. Signed overflow can occur before the new FSIZE_t range check.

   Locations:

   • components/dfs/dfs_v2/src/dfs_file.c:1192-1194
   • components/dfs/dfs_v2/filesystems/elmfat/dfs_elm.c:668-674

   SEEK_CUR and SEEK_END calculate base + offset first, while dfs_elm_off_to_fsize() validates the result only afterwards. With RT_USING_DFS_LARGE_FILE, off_t is int64_t; an input such as INT64_MAX plus a non-zero current position invokes signed-overflow undefined behavior before the conversion helper can reject it. Depending on optimization and architecture, this can produce a negative/wrapped position or bypass the intended range check.

   Please use a checked-add helper and return -EOVERFLOW before performing the addition. For example:

   if ((offset > 0 && base > INT64_MAX - offset) ||
       (offset < 0 && base < INT64_MIN - offset))
       return -EOVERFLOW;
   result = base + offset;

   The same boundary behavior should be covered for SEEK_SET, SEEK_CUR, SEEK_END, ftruncate, read/write, and both DFS v1/v2 configurations where applicable. Test INT64_MAX, INT64_MIN, negative offsets, and values just beyond the FatFS FSIZE_t limit.

一般 / General

2. dfs_elm_off_to_fsize() is duplicated in the v1 and v2 ELM implementations. A shared checked-conversion helper would reduce the chance that one implementation receives a future overflow fix while the other does not.

3. This PR changes the public off_t and struct stat ABI behind a Kconfig switch. Please document the required full-image rebuild/configuration consistency and provide at least one 32-bit target test with FSIZE_t narrower than off_t.

4. The required PR description still contains the untouched template and does not state the tested BSP/configuration. Please fill it in before merge so reviewers can reproduce the large-file paths.