c/libuv
1
0
Fork 0
mirror of https://github.com/libuv/libuv synced 2025-03-28 21:13:16 +00:00
Code Issues Packages Projects Releases Wiki Activity

kqueue: disallow ill-suited file descriptor kinds (#4513)

Browse Source 
Follows up on https://github.com/libuv/libuv/pull/659.

Signed-off-by: Andy Pan <i@andypan.me>
This commit is contained in:
Andy Pan 2024-09-10 02:22:15 +08:00 committed by GitHub
parent 0a00e80c36
commit 44e61dab7e
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 78 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
src/unix/kqueue.c
View File

@ -99,6 +99,39 @@ int uv__io_fork(uv_loop_t* loop) {
int uv__io_check_fd(uv_loop_t* loop, int fd) {
struct kevent ev;
int rc;
struct stat sb;
#ifdef __APPLE__
char path[MAXPATHLEN];
#endif
if (uv__fstat(fd, &sb))
return UV__ERR(errno);
/* On FreeBSD, kqueue only supports EVFILT_READ notification for regular files
* and always reports ready events for writing, resulting in busy-looping.
*
* On Darwin, DragonFlyBSD, NetBSD and OpenBSD, kqueue reports ready events for
* regular files as readable and writable only once, acting like an EV_ONESHOT.
*
* Neither of the above cases should be added to the kqueue.
*/
if (S_ISREG(sb.st_mode) || S_ISDIR(sb.st_mode))
return UV_EINVAL;
#ifdef __APPLE__
/* On Darwin (both macOS and iOS), in addition to regular files, FIFOs also don't
* work properly with kqueue: the disconnection from the last writer won't trigger
* an event for kqueue in spite of what the man pages say. Thus, we also disallow
* the case of S_IFIFO. */
if (S_ISFIFO(sb.st_mode)) {
/* File descriptors of FIFO, pipe and kqueue share the same type of file,
* therefore there is no way to tell them apart via stat.st_mode&S_IFMT.
* Fortunately, FIFO is the only one that has a persisted file on filesystem,
* from which we're able to make the distinction for it. */
if (!fcntl(fd, F_GETPATH, path))
return UV_EINVAL;
}
#endif
rc = 0;
EV_SET(&ev, fd, EVFILT_READ, EV_ADD, 0, 0, 0);

57
test/test-poll.c
View File

@ -626,26 +626,59 @@ TEST_IMPL(poll_unidirectional) {
/* Windows won't let you open a directory so we open a file instead.
* OS X lets you poll a file so open the $PWD instead. Both fail
* on Linux so it doesn't matter which one we pick. Both succeed
* on FreeBSD, Solaris and AIX so skip the test on those platforms.
* OS X lets you poll a file so open the $PWD instead. Both fail
* on Linux so it doesn't matter which one we pick. Both succeed
* on Solaris and AIX so skip the test on those platforms.
* On *BSD/Darwin, we disallow polling of regular files, directories.
* In addition to regular files, we also disallow FIFOs on Darwin.
*/
#ifdef __APPLE__
#define TEST_POLL_FIFO_PATH "/tmp/uv-test-poll-fifo"
#endif
TEST_IMPL(poll_bad_fdtype) {
#if !defined(__DragonFly__) && !defined(__FreeBSD__) && !defined(__sun) && \
#if !defined(__sun) && \
!defined(_AIX) && !defined(__MVS__) && \
!defined(__OpenBSD__) && !defined(__CYGWIN__) && !defined(__MSYS__) && \
!defined(__NetBSD__)
!defined(__CYGWIN__) && !defined(__MSYS__)
uv_poll_t poll_handle;
int fd;
int fd[2];
#if defined(_WIN32)
fd = _open("test/fixtures/empty_file", UV_FS_O_RDONLY);
fd[0] = _open("test/fixtures/empty_file", UV_FS_O_RDONLY);
#else
fd = open(".", UV_FS_O_RDONLY);
fd[0] = open(".", UV_FS_O_RDONLY);
#endif
ASSERT_NE(fd[0], -1);
ASSERT_NE(0, uv_poll_init(uv_default_loop(), &poll_handle, fd[0]));
ASSERT_OK(close(fd[0]));
#if defined(__APPLE__) || \
defined(__DragonFly__) || \
defined(__FreeBSD__) || \
defined(__OpenBSD__) || \
defined(__NetBSD__)
fd[0] = open("test/fixtures/empty_file", UV_FS_O_RDONLY);
ASSERT_NE(fd[0], -1);
/* Regular files should be banned from kqueue. */
ASSERT_NE(0, uv_poll_init(uv_default_loop(), &poll_handle, fd[0]));
ASSERT_OK(close(fd[0]));
#ifdef __APPLE__
ASSERT_OK(pipe(fd));
/* Pipes should be permitted in kqueue. */
ASSERT_EQ(0, uv_poll_init(uv_default_loop(), &poll_handle, fd[0]));
ASSERT_OK(close(fd[0]));
ASSERT_OK(close(fd[1]));
ASSERT_OK(mkfifo(TEST_POLL_FIFO_PATH, 0600));
fd[0] = open(TEST_POLL_FIFO_PATH, O_RDONLY | O_NONBLOCK);
ASSERT_NE(fd[0], -1);
fd[1] = open(TEST_POLL_FIFO_PATH, O_WRONLY | O_NONBLOCK);
ASSERT_NE(fd[1], -1);
/* FIFOs should be banned from kqueue. */
ASSERT_NE(0, uv_poll_init(uv_default_loop(), &poll_handle, fd[0]));
ASSERT_OK(close(fd[0]));
ASSERT_OK(close(fd[1]));
unlink(TEST_POLL_FIFO_PATH);
#endif
#endif
ASSERT_NE(fd, -1);
ASSERT_NE(0, uv_poll_init(uv_default_loop(), &poll_handle, fd));
ASSERT_OK(close(fd));
#endif
MAKE_VALGRIND_HAPPY(uv_default_loop());