1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145
|
From: Gabriele Svelto <gsvelto@mozilla.com>
Date: Mon, 28 Oct 2019 23:26:00 +0000
Subject: Bug 1590984 - Use poll() instead of select() in WebRTC code r=drno
The use of select() was leading to crashes when the file descriptor value was
larger than FD_SETSIZE. Recent versions of glibc have checks in the FD_CLR(),
FD_SET() and FD_ISSET() macros that will abort() the program instead of doing
an out-of-bounds access. poll() doesn't have limitations on the file
descriptor values and provides behavior that is otherwise identical to
select() thus solving the problem.
Differential Revision: https://phabricator.services.mozilla.com/D50798
Mercurial Revision: https://hg.mozilla.org/mozilla-central/rev/59fb6760bb6785a6f8a51be6fc66bf04cfba3e16
---
.../video_capture/linux/device_info_linux.cc | 1 +
.../video_capture/linux/device_info_v4l2.cc | 16 +++++-----
.../linux/video_capture_linux.cc | 1 +
.../video_capture/linux/video_capture_v4l2.cc | 29 +++++++++++--------
4 files changed, 26 insertions(+), 21 deletions(-)
diff --git a/modules/video_capture/linux/device_info_linux.cc b/modules/video_capture/linux/device_info_linux.cc
index 56da475bf3..cae63c7c2d 100644
--- a/modules/video_capture/linux/device_info_linux.cc
+++ b/modules/video_capture/linux/device_info_linux.cc
@@ -10,6 +10,7 @@
#include <errno.h>
#include <fcntl.h>
+#include <poll.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
diff --git a/modules/video_capture/linux/device_info_v4l2.cc b/modules/video_capture/linux/device_info_v4l2.cc
index f77d791033..a2435bcd4f 100644
--- a/modules/video_capture/linux/device_info_v4l2.cc
+++ b/modules/video_capture/linux/device_info_v4l2.cc
@@ -12,6 +12,7 @@
#include <errno.h>
#include <fcntl.h>
+#include <poll.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@@ -91,16 +92,13 @@ void DeviceInfoV4l2::HandleEvent(inotify_event* event, int fd)
int DeviceInfoV4l2::EventCheck(int fd)
{
- struct timeval timeout;
- fd_set rfds;
+ struct pollfd fds = {
+ .fd = fd,
+ .events = POLLIN,
+ .revents = 0
+ };
- timeout.tv_sec = 0;
- timeout.tv_usec = 100000;
-
- FD_ZERO(&rfds);
- FD_SET(fd, &rfds);
-
- return select(fd+1, &rfds, NULL, NULL, &timeout);
+ return poll(&fds, 1, 100);
}
int DeviceInfoV4l2::HandleEvents(int fd)
diff --git a/modules/video_capture/linux/video_capture_linux.cc b/modules/video_capture/linux/video_capture_linux.cc
index 1c635ea440..7872662fae 100644
--- a/modules/video_capture/linux/video_capture_linux.cc
+++ b/modules/video_capture/linux/video_capture_linux.cc
@@ -10,6 +10,7 @@
#include <errno.h>
#include <fcntl.h>
+#include <poll.h>
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
diff --git a/modules/video_capture/linux/video_capture_v4l2.cc b/modules/video_capture/linux/video_capture_v4l2.cc
index 33aa452a07..ccb6b79630 100644
--- a/modules/video_capture/linux/video_capture_v4l2.cc
+++ b/modules/video_capture/linux/video_capture_v4l2.cc
@@ -12,7 +12,7 @@
#include <errno.h>
#include <fcntl.h>
-#include <linux/videodev2.h>
+#include <poll.h>
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
@@ -20,6 +20,14 @@
#include <sys/select.h>
#include <time.h>
#include <unistd.h>
+// v4l includes
+#if defined(__NetBSD__) || defined(__OpenBSD__) // WEBRTC_BSD
+#include <sys/videoio.h>
+#elif defined(__sun)
+#include <sys/videodev2.h>
+#else
+#include <linux/videodev2.h>
+#endif
#include <new>
#include <string>
@@ -411,16 +419,13 @@ bool VideoCaptureModuleV4L2::CaptureProcess() {
RTC_CHECK_RUNS_SERIALIZED(&capture_checker_);
int retVal = 0;
- fd_set rSet;
- struct timeval timeout;
+ struct pollfd rSet;
- FD_ZERO(&rSet);
- FD_SET(_deviceFd, &rSet);
- timeout.tv_sec = 1;
- timeout.tv_usec = 0;
+ rSet.fd = _deviceFd;
+ rSet.events = POLLIN;
+ rSet.revents = 0;
- // _deviceFd written only in StartCapture, when this thread isn't running.
- retVal = select(_deviceFd + 1, &rSet, NULL, NULL, &timeout);
+ retVal = poll(&rSet, 1, 1000);
{
MutexLock lock(&capture_lock_);
@@ -430,12 +435,12 @@ bool VideoCaptureModuleV4L2::CaptureProcess() {
}
if (retVal < 0 && errno != EINTR) { // continue if interrupted
- // select failed
+ // poll failed
return false;
} else if (retVal == 0) {
- // select timed out
+ // poll timed out
return true;
- } else if (!FD_ISSET(_deviceFd, &rSet)) {
+ } else if (!(rSet.revents & POLLIN)) {
// not event on camera handle
return true;
}
|