openssl/openssl

win32_joiner() in crypto/dso/dso_win32.c writes 1 byte past the allocation when the directory has no trailing separator and file is NULL

Open

#31,260 建立於 2026年5月20日

在 GitHub 查看
 (2 留言) (0 反應) (0 負責人)C (30,157 star) (11,262 fork)batch import
branch: 3.0branch: 3.4branch: 3.5branch: 3.6branch: 4.0good first issuetriaged: bug

描述

In win32_joiner() (crypto/dso/dso_win32.c), the directory trailing-separator is budgeted into len only when file_split->file is non-NULL but is emitted unconditionally by the directory loop; when dir is set without a trailing separator and file == NULL, the final result[offset] = '\0' writes one byte past OPENSSL_malloc(len + 1).

貢獻者指南

技術棧
c
領域
securitybackend
議題類型
bug
難度面向新貢獻者的預計實作難度，1 表示很小改動，5 表示專家級工作。
3
預計時間有經驗貢獻者完成調查、實作、測試並準備 pull request 的粗略時間範圍。
1-3 hours
活動狀態議題目前的可參與程度：新鮮、活躍、陳舊、阻塞或等待維護者輸入。
fresh
清晰度議題是否清楚說明預期改動、驗收標準和下一步。
clear
前置要求
C programmingknowledge of memory management
新手友善度1-100 的估計分數，表示該議題對首次貢獻者的友善程度。
35
研究方向
The issue is in crypto/dso/dso win32.c, function win32 joiner(). The bug occurs when directory has no trailing separator and file is NULL, causing a buffer overflow. To fix, ensure that the null terminator is only written within allocated bounds, or adjust allocation to account for the separator when dir lacks it. The fix should check if file split >file is NULL when adding the separator, and only allocate extra byte if needed.