gh-123014: Disable pidfd API on older Android versions (#124458)

mhsmith · mhsmith · commit 7c4724f642a2 · 2024-09-25T20:53:08.000+01:00
(cherry picked from commit c58c572)
diff --git a/Doc/library/os.rst b/Doc/library/os.rst
@@ -4572,7 +4572,7 @@ written in Python, such as a mail server's external command delivery program.
 
    See the :manpage:`pidfd_open(2)` man page for more details.
 
-   .. availability:: Linux >= 5.3
+   .. availability:: Linux >= 5.3, Android >= :func:`build-time <sys.getandroidapilevel>` API level 31
    .. versionadded:: 3.9
 
    .. data:: PIDFD_NONBLOCK
diff --git a/Doc/library/signal.rst b/Doc/library/signal.rst
@@ -411,7 +411,7 @@ The :mod:`signal` module defines the following functions:
 
    See the :manpage:`pidfd_send_signal(2)` man page for more information.
 
-   .. availability:: Linux >= 5.1
+   .. availability:: Linux >= 5.1, Android >= :func:`build-time <sys.getandroidapilevel>` API level 31
    .. versionadded:: 3.9
 
 
diff --git a/Misc/NEWS.d/next/Library/2024-09-24-19-32-14.gh-issue-123014.zVcfkZ.rst b/Misc/NEWS.d/next/Library/2024-09-24-19-32-14.gh-issue-123014.zVcfkZ.rst
@@ -0,0 +1,3 @@
+:func:`os.pidfd_open` and :func:`signal.pidfd_send_signal` are now
+unavailable when building against Android API levels older than 31, since
+the underlying system calls may cause a crash.
diff --git a/Modules/clinic/posixmodule.c.h b/Modules/clinic/posixmodule.c.h
diff --git a/Modules/clinic/signalmodule.c.h b/Modules/clinic/signalmodule.c.h
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
@@ -10102,7 +10102,10 @@ os_wait_impl(PyObject *module)
 }
 #endif /* HAVE_WAIT */
 
-#if defined(__linux__) && defined(__NR_pidfd_open)
+
+// This system call always crashes on older Android versions.
+#if defined(__linux__) && defined(__NR_pidfd_open) && \
+    !(defined(__ANDROID__) && __ANDROID_API__ < 31)
 /*[clinic input]
 os.pidfd_open
   pid: pid_t
diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c
@@ -1299,7 +1299,9 @@ signal_pthread_kill_impl(PyObject *module, unsigned long thread_id,
 #endif   /* #if defined(HAVE_PTHREAD_KILL) */
 
 
-#if defined(__linux__) && defined(__NR_pidfd_send_signal)
+// This system call always crashes on older Android versions.
+#if defined(__linux__) && defined(__NR_pidfd_send_signal) && \
+    !(defined(__ANDROID__) && __ANDROID_API__ < 31)
 /*[clinic input]
 signal.pidfd_send_signal
 

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	+:func:`os.pidfd_open` and :func:`signal.pidfd_send_signal` are now
	`2`	`+unavailable when building against Android API levels older than 31, since`
	`3`	`+the underlying system calls may cause a crash.`