Module Name: src
Committed By: kamil
Date: Wed May 31 00:45:59 UTC 2017
Modified Files:
src/sys/sys: event.h
Log Message:
Convert EV_SET from macro to static __inline function
LLDB introduced support for kevent(2) and it contains the following function:
Status MainLoop::RunImpl::Poll() {
in_events.resize(loop.m_read_fds.size());
unsigned i = 0;
for (auto &fd : loop.m_read_fds)
EV_SET(&in_events[i++], fd.first, EVFILT_READ, EV_ADD, 0, 0, 0);
num_events = kevent(loop.m_kqueue, in_events.data(), in_events.size(),
out_events, llvm::array_lengthof(out_events), nullptr);
if (num_events < 0)
return Status("kevent() failed with error %d\n", num_events);
return Status();
}
It works on FreeBSD and MacOSX, however it broke on NetBSD.
Culrpit line:
EV_SET(&in_events[i++], fd.first, EVFILT_READ, EV_ADD, 0, 0, 0);
FreeBSD defined EV_SET() as a macro this way:
#define EV_SET(kevp_, a, b, c, d, e, f) do { \
struct kevent *kevp = (kevp_); \
(kevp)->ident = (a); \
(kevp)->filter = (b); \
(kevp)->flags = (c); \
(kevp)->fflags = (d); \
(kevp)->data = (e); \
(kevp)->udata = (f); \
} while(0)
NetBSD version was different:
#define EV_SET(kevp, a, b, c, d, e, f) \
do { \
(kevp)->ident = (a); \
(kevp)->filter = (b); \
(kevp)->flags = (c); \
(kevp)->fflags = (d); \
(kevp)->data = (e); \
(kevp)->udata = (f); \
} while (/* CONSTCOND */ 0)
This resulted in heap damage, as keyp was incremented every time value was
assigned to (keyp)->.
As suggested by Joerg, convert this macro on NetBSD to static __inline
function.
Credit to <coypu> for asan+ubsan research wiki entry that helped to narrow
down the bug.
Credit to <joerg> for peer-review
Sponsored by <The NetBSD Foundation>
To generate a diff of this commit:
cvs rdiff -u -r1.26 -r1.27 src/sys/sys/event.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/sys/event.h
diff -u src/sys/sys/event.h:1.26 src/sys/sys/event.h:1.27
--- src/sys/sys/event.h:1.26 Sun Jan 31 04:40:01 2016
+++ src/sys/sys/event.h Wed May 31 00:45:59 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: event.h,v 1.26 2016/01/31 04:40:01 christos Exp $ */
+/* $NetBSD: event.h,v 1.27 2017/05/31 00:45:59 kamil Exp $ */
/*-
* Copyright (c) 1999,2000,2001 Jonathan Lemon <jle...@freebsd.org>
@@ -45,17 +45,6 @@
#define EVFILT_TIMER 6U /* arbitrary timer (in ms) */
#define EVFILT_SYSCOUNT 7U /* number of filters */
-#define EV_SET(kevp, a, b, c, d, e, f) \
-do { \
- (kevp)->ident = (a); \
- (kevp)->filter = (b); \
- (kevp)->flags = (c); \
- (kevp)->fflags = (d); \
- (kevp)->data = (e); \
- (kevp)->udata = (f); \
-} while (/* CONSTCOND */ 0)
-
-
struct kevent {
uintptr_t ident; /* identifier for this event */
uint32_t filter; /* filter for event */
@@ -65,6 +54,18 @@ struct kevent {
intptr_t udata; /* opaque user data identifier */
};
+static __inline void
+EV_SET(struct kevent *_kevp, uintptr_t _ident, uint32_t _filter,
+ uint32_t _flags, uint32_t _fflags, int64_t _data, intptr_t _udata)
+{
+ _kevp->ident = _ident;
+ _kevp->filter = _filter;
+ _kevp->flags = _flags;
+ _kevp->fflags = _fflags;
+ _kevp->data = _data;
+ _kevp->udata = _udata;
+}
+
/* actions */
#define EV_ADD 0x0001U /* add event to kq (implies ENABLE) */
#define EV_DELETE 0x0002U /* delete event from kq */
