linux-kernel - [PATCH v2 0/2] seccomp: Fix a race with WAIT_KILLABLE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250725-seccomp-races-v2-0-cf8b9d139596@nixdorf.dev>
Date: Fri, 25 Jul 2025 18:31:17 +0200
From: Johannes Nixdorf <johannes@...dorf.dev>
To: Kees Cook <kees@...nel.org>, Andy Lutomirski <luto@...capital.net>, 
 Will Drewry <wad@...omium.org>, Sargun Dhillon <sargun@...gun.me>, 
 Shuah Khan <shuah@...nel.org>
Cc: linux-kernel@...r.kernel.org, Ali Polatel <alip@...sswob.org>, 
 linux-kselftest@...r.kernel.org, bpf@...r.kernel.org, 
 Johannes Nixdorf <johannes@...dorf.dev>
Subject: [PATCH v2 0/2] seccomp: Fix a race with WAIT_KILLABLE_RECV if the
 tracer replies too fast

If WAIT_KILLABLE_RECV was specified, and an event is received, the
tracee's syscall is not supposed to be interruptible. This was not properly
ensured if the reply was sent too fast, and an interrupting signal was
received before the reply was processed on the tracee side.

This series fixes the bug and adds a test case for it to the selftests.

Signed-off-by: Johannes Nixdorf <johannes@...dorf.dev>
---
Changes in v2:
- Added a selftest for the bug.
- Link to v1: https://lore.kernel.org/r/20250723-seccomp-races-v1-1-bef5667ce30a@nixdorf.dev

---
Johannes Nixdorf (2):
      seccomp: Fix a race with WAIT_KILLABLE_RECV if the tracer replies too fast
      selftests/seccomp: Add a test for the WAIT_KILLABLE_RECV fast reply race

 kernel/seccomp.c                              |  13 ++-
 tools/testing/selftests/seccomp/seccomp_bpf.c | 130 ++++++++++++++++++++++++++
 2 files changed, 136 insertions(+), 7 deletions(-)
---
base-commit: 89be9a83ccf1f88522317ce02f854f30d6115c41
change-id: 20250721-seccomp-races-e97897d6d94b

Best regards,
-- 
Johannes Nixdorf <johannes@...dorf.dev>