[adilalperenciftci]

Summary

Enforce bounds checking on signalfd notification registrations and cleanly detach notification listeners during signalfd_close.

Technical Breakdown

1. Replace unsafe global index counter with per-context slot lookup bounded by SIGNALFD_SHART_MAX.
2. In signalfd_close, iterate registered lwps, detach matching notification nodes from signalfd_notify_head, and free allocated listener structures.
3. Reset file context pointer and initialize table entries to prevent stale dereferencing.

Fixes: #11933

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[github-actions]

📌 Code Review Assignment

🏷️ Tag: components

Reviewers: @Maihuanyi

Changed Files (Click to expand)

• components/libc/posix/io/signalfd/signalfd.c

🏷️ Tag: components_libc

Reviewers: @GorrayLi @mysterywolf

Changed Files (Click to expand)

• components/libc/posix/io/signalfd/signalfd.c

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📊 Current Review Status (Last Updated: 2026-10-27 08:34 CST)

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

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[github-actions]

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