diff options
Diffstat (limited to 'backport-sd-event-fix-fd-leak-when-fd-is-owned-by-IO-event-source.patch')
| -rw-r--r-- | backport-sd-event-fix-fd-leak-when-fd-is-owned-by-IO-event-source.patch | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/backport-sd-event-fix-fd-leak-when-fd-is-owned-by-IO-event-source.patch b/backport-sd-event-fix-fd-leak-when-fd-is-owned-by-IO-event-source.patch new file mode 100644 index 0000000..1250f84 --- /dev/null +++ b/backport-sd-event-fix-fd-leak-when-fd-is-owned-by-IO-event-source.patch @@ -0,0 +1,152 @@ +From 2c30104f8344406e71b792a8691af60af3afe177 Mon Sep 17 00:00:00 2001 +From: Yu Watanabe <watanabe.yu+github@gmail.com> +Date: Tue, 2 Jul 2024 09:55:57 +0800 +Subject: [PATCH] sd-event: fix fd leak when fd is owned by IO event source + When an IO event source owns relevant fd, replacing with a new fd leaks the + previously assigned fd. === sd_event_add_io(event, &s, fd, ...); + sd_event_source_set_io_fd_own(s, true); sd_event_source_set_io_fd(s, new_fd); + <-- The previous fd is not closed. sd_event_source_unref(s); <-- new_fd is + closed as expected. === + +Without the change, valgrind reports the leak: +==998589== +==998589== FILE DESCRIPTORS: 4 open (3 std) at exit. +==998589== Open file descriptor 4: +==998589== at 0x4F119AB: pipe2 (in /usr/lib64/libc.so.6) +==998589== by 0x408830: test_sd_event_source_set_io_fd (test-event.c:862) +==998589== by 0x403302: run_test_table (tests.h:171) +==998589== by 0x408E31: main (test-event.c:935) +==998589== +==998589== +==998589== HEAP SUMMARY: +==998589== in use at exit: 0 bytes in 0 blocks +==998589== total heap usage: 33,305 allocs, 33,305 frees, 1,283,581 bytes allocated +==998589== +==998589== All heap blocks were freed -- no leaks are possible +==998589== +==998589== For lists of detected and suppressed errors, rerun with: -s +==998589== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0) + +(cherry picked from commit 2fa4805) +(cherry picked from commit 6d2dd43) +(cherry picked from commit 5f8cf63) + +Conflict:test case adaptation +Reference:https://github.com/systemd/systemd-stable/commit/a4bb56c61a7bfef9bab3380b3c18709ab8fef3d8 +--- + man/sd_event_add_io.xml | 24 ++++++++++++++---------- + src/libsystemd/sd-event/sd-event.c | 17 ++++++++--------- + src/libsystemd/sd-event/test-event.c | 18 ++++++++++++++++++ + 3 files changed, 40 insertions(+), 19 deletions(-) + +diff --git a/man/sd_event_add_io.xml b/man/sd_event_add_io.xml +index da0fa58..9d4fd27 100644 +--- a/man/sd_event_add_io.xml ++++ b/man/sd_event_add_io.xml +@@ -216,16 +216,20 @@ + source object and returns the non-negative file descriptor + or a negative error number on error (see below).</para> + +- <para><function>sd_event_source_set_io_fd()</function> +- changes the UNIX file descriptor of an I/O event source created +- previously with <function>sd_event_add_io()</function>. It takes +- the event source object and the new file descriptor.</para> +- +- <para><function>sd_event_source_set_io_fd_own()</function> controls whether the file descriptor of the event source +- shall be closed automatically when the event source is freed, i.e. whether it shall be considered 'owned' by the +- event source object. By default it is not closed automatically, and the application has to do this on its own. The +- <parameter>b</parameter> parameter is a boolean parameter: if zero, the file descriptor is not closed automatically +- when the event source is freed, otherwise it is closed.</para> ++ <para><function>sd_event_source_set_io_fd()</function> changes the UNIX file descriptor of an I/O event ++ source created previously with <function>sd_event_add_io()</function>. It takes the event source object ++ and the new file descriptor. If the event source takes the ownership of the previous file descriptor, ++ that is, <function>sd_event_source_set_io_fd_own()</function> was called for the event source with a ++ non-zero value, then the previous file descriptor will be closed and the event source will also take the ++ ownership of the new file descriptor on success.</para> ++ ++ <para><function>sd_event_source_set_io_fd_own()</function> controls whether the file descriptor of the ++ event source shall be closed automatically when the event source is freed (or when the file descriptor ++ assigned to the event source is replaced by <function>sd_event_source_set_io_fd()</function>), i.e. ++ whether it shall be considered 'owned' by the event source object. By default it is not closed ++ automatically, and the application has to do this on its own. The <parameter>b</parameter> parameter is a ++ boolean parameter: if zero, the file descriptor is not closed automatically when the event source is ++ freed, otherwise it is closed.</para> + + <para><function>sd_event_source_get_io_fd_own()</function> may be used to query the current setting of the file + descriptor ownership boolean flag as set with <function>sd_event_source_set_io_fd_own()</function>. It returns +diff --git a/src/libsystemd/sd-event/sd-event.c b/src/libsystemd/sd-event/sd-event.c +index d53a7a1..0b59f63 100644 +--- a/src/libsystemd/sd-event/sd-event.c ++++ b/src/libsystemd/sd-event/sd-event.c +@@ -2696,7 +2696,7 @@ _public_ int sd_event_source_get_io_fd(sd_event_source *s) { + } + + _public_ int sd_event_source_set_io_fd(sd_event_source *s, int fd) { +- int r; ++ int saved_fd, r; + + assert_return(s, -EINVAL); + assert_return(fd >= 0, -EBADF); +@@ -2706,16 +2706,12 @@ _public_ int sd_event_source_set_io_fd(sd_event_source *s, int fd) { + if (s->io.fd == fd) + return 0; + +- if (event_source_is_offline(s)) { +- s->io.fd = fd; +- s->io.registered = false; +- } else { +- int saved_fd; ++ saved_fd = s->io.fd; ++ s->io.fd = fd; + +- saved_fd = s->io.fd; +- assert(s->io.registered); ++ assert(event_source_is_offline(s) == !s->io.registered); + +- s->io.fd = fd; ++ if (s->io.registered) { + s->io.registered = false; + + r = source_io_register(s, s->enabled, s->io.events); +@@ -2727,6 +2723,9 @@ _public_ int sd_event_source_set_io_fd(sd_event_source *s, int fd) { + + (void) epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, saved_fd, NULL); + } ++ ++ if (s->io.owned) ++ safe_close(saved_fd); + + return 0; + } +diff --git a/src/libsystemd/sd-event/test-event.c b/src/libsystemd/sd-event/test-event.c +index 63d3ee7..695b0ed 100644 +--- a/src/libsystemd/sd-event/test-event.c ++++ b/src/libsystemd/sd-event/test-event.c +@@ -809,6 +809,24 @@ TEST(inotify_process_buffered_data) { + assert_se(sd_event_wait(e, 0) == 0); + } + ++TEST(sd_event_source_set_io_fd) { ++ _cleanup_(sd_event_source_unrefp) sd_event_source *s = NULL; ++ _cleanup_(sd_event_unrefp) sd_event *e = NULL; ++ _cleanup_close_pair_ int pfd_a[2] = { -EBADF, -EBADF }, pfd_b[2] = { -EBADF, -EBADF }; ++ ++ assert_se(sd_event_default(&e) >= 0); ++ ++ assert_se(pipe2(pfd_a, O_CLOEXEC) >= 0); ++ assert_se(pipe2(pfd_b, O_CLOEXEC) >= 0); ++ ++ assert_se(sd_event_add_io(e, &s, pfd_a[0], EPOLLIN, NULL, INT_TO_PTR(-ENOANO)) >= 0); ++ assert_se(sd_event_source_set_io_fd_own(s, true) >= 0); ++ TAKE_FD(pfd_a[0]); ++ ++ assert_se(sd_event_source_set_io_fd(s, pfd_b[0]) >= 0); ++ TAKE_FD(pfd_b[0]); ++} ++ + TEST(fork) { + _cleanup_(sd_event_unrefp) sd_event *e = NULL; + int r; +-- +2.27.0 + |