Mercurial > cpython-lru_cache-weakref
changeset 86682:021ca321b26e 3.3
Issue #19227: Try to fix deadlocks caused by re-seeding then OpenSSL
pseudo-random number generator on fork().
| author | Georg Brandl <georg@python.org> |
|---|---|
| date | Sun, 27 Oct 2013 07:56:11 +0100 |
| parents | 49be8a5c9de2 |
| children | d3a13a7be9e9 71568a354798 |
| files | Misc/NEWS Modules/_ssl.c |
| diffstat | 2 files changed, 11 insertions(+), 7 deletions(-) [+] |
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--- a/Misc/NEWS Sun Oct 27 07:39:36 2013 +0100 +++ b/Misc/NEWS Sun Oct 27 07:56:11 2013 +0100 @@ -81,6 +81,9 @@ Library ------- +- Issue #19227: Try to fix deadlocks caused by re-seeding then OpenSSL + pseudo-random number generator on fork(). + - Issue #16037: HTTPMessage.readheaders() raises an HTTPException when more than 100 headers are read. Adapted from patch by Jyrki Pulliainen.
--- a/Modules/_ssl.c Sun Oct 27 07:39:36 2013 +0100 +++ b/Modules/_ssl.c Sun Oct 27 07:56:11 2013 +0100 @@ -2586,7 +2586,7 @@ /* Seed OpenSSL's PRNG at fork(), http://bugs.python.org/issue18747 * - * The parent handler seeds the PRNG from pseudo-random data like pid, the + * The prepare handler seeds the PRNG from pseudo-random data like pid, the * current time (miliseconds or seconds) and an uninitialized array. * The array contains stack variables that are impossible to predict * on most systems, e.g. function return address (subject to ASLR), the @@ -2595,16 +2595,17 @@ * * Note: * The code uses pthread_atfork() until Python has a proper atfork API. The - * handlers are not removed from the child process. A parent handler is used + * handlers are not removed from the child process. A prepare handler is used * instead of a child handler because fork() is supposed to be async-signal - * safe but the handler calls unsafe functions. + * safe but the handler calls unsafe functions. A parent handler has caused + * other problems, see issue #19227. */ #if defined(HAVE_PTHREAD_ATFORK) && defined(WITH_THREAD) #define PYSSL_RAND_ATFORK 1 static void -PySSL_RAND_atfork_parent(void) +PySSL_RAND_atfork_prepare(void) { struct { char stack[128]; /* uninitialized (!) stack data, 128 is an @@ -2630,9 +2631,9 @@ if (registered) return 0; - retval = pthread_atfork(NULL, /* prepare */ - PySSL_RAND_atfork_parent, /* parent */ - NULL); /* child */ + retval = pthread_atfork(PySSL_RAND_atfork_prepare, /* prepare */ + NULL, /* parent */ + NULL); /* child */ if (retval != 0) { PyErr_SetFromErrno(PyExc_OSError); return -1;
