Merge tag 'pull-misc-20240805' of https://gitlab.com/rth7680/qemu into staging
linux-user/elfload: Fix pr_pid values in core files
util: Add qemu_close_all_open_fd
net/tap: Use qemu_close_all_open_fd
# -----BEGIN PGP SIGNATURE-----
#
# iQFRBAABCgA7FiEEekgeeIaLTbaoWgXAZN846K9+IV8FAmawHSsdHHJpY2hhcmQu
# aGVuZGVyc29uQGxpbmFyby5vcmcACgkQZN846K9+IV8mhQgAlNjO1eeeQmgJvKpk
# BwXx7NnXi9d8UZCA5EASK9SQVJC3eYIlMayX9byPmZZ6XJaOBRzgIzm612HkKLYn
# yIqmLb0UhUTT+VKW7Kob/wGslB/PJWSKQ3dvZFaaLMfB6L3BtpwUAFFU5hwkODU/
# TS4qici1W+eW7hInNSH5dgA68UGPcfDBEo4ITW91DbTSZRNz9RP4b2Ak+Wgv30Ux
# 2yEVsP6rBqBSxglbafcywWbYs5sX3EvSUJo4mVm8Ku4zriAf87Y9Da3irpZ4WYgi
# 02f+/GGAv9kiGbf9jPrQTD0O8tmp4Z6JMWxEOfMsCj+KCT2fHSSqcBHTU3RN0guB
# uaxx6w==
# =U5cs
# -----END PGP SIGNATURE-----
# gpg: Signature made Mon 05 Aug 2024 10:30:35 AM AEST
# gpg: using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg: issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [ultimate]
* tag 'pull-misc-20240805' of https://gitlab.com/rth7680/qemu:
net/tap: Use qemu_close_all_open_fd()
qemu/osdep: Add excluded fd parameter to qemu_close_all_open_fd()
net/tap: Factorize fd closing after forking
qemu/osdep: Split qemu_close_all_open_fd() and add fallback
qemu/osdep: Move close_all_open_fds() to oslib-posix
linux-user/elfload: Fix pr_pid values in core files
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
index 720ed21..4cc4c32 100644
--- a/include/qemu/osdep.h
+++ b/include/qemu/osdep.h
@@ -758,6 +758,17 @@
int qemu_fdatasync(int fd);
/**
+ * qemu_close_all_open_fd:
+ *
+ * Close all open file descriptors except the ones supplied in the @skip array
+ *
+ * @skip: ordered array of distinct file descriptors that should not be closed
+ * if any, or NULL.
+ * @nskip: number of entries in the @skip array or 0 if @skip is NULL.
+ */
+void qemu_close_all_open_fd(const int *skip, unsigned int nskip);
+
+/**
* Sync changes made to the memory mapped file back to the backing
* storage. For POSIX compliant systems this will fallback
* to regular msync call. Otherwise it will trigger whole file sync
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 0d4dc1f..b27dd01 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -4102,8 +4102,7 @@
bswap_phdr(phdr, 1);
}
-static void fill_prstatus_note(void *data, const TaskState *ts,
- CPUState *cpu, int signr)
+static void fill_prstatus_note(void *data, CPUState *cpu, int signr)
{
/*
* Because note memory is only aligned to 4, and target_elf_prstatus
@@ -4113,7 +4112,7 @@
struct target_elf_prstatus prstatus = {
.pr_info.si_signo = signr,
.pr_cursig = signr,
- .pr_pid = ts->ts_tid,
+ .pr_pid = get_task_state(cpu)->ts_tid,
.pr_ppid = getppid(),
.pr_pgrp = getpgrp(),
.pr_sid = getsid(0),
@@ -4428,8 +4427,7 @@
CPU_FOREACH(cpu_iter) {
dptr = fill_note(&hptr, NT_PRSTATUS, "CORE",
sizeof(struct target_elf_prstatus));
- fill_prstatus_note(dptr, ts, cpu_iter,
- cpu_iter == cpu ? signr : 0);
+ fill_prstatus_note(dptr, cpu_iter, cpu_iter == cpu ? signr : 0);
}
if (dump_write(fd, header, data_offset) < 0) {
diff --git a/net/tap.c b/net/tap.c
index 51f7aec..3f90022 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -385,6 +385,24 @@
return s;
}
+static void close_all_fds_after_fork(int excluded_fd)
+{
+ const int skip_fd[] = {STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO,
+ excluded_fd};
+ unsigned int nskip = ARRAY_SIZE(skip_fd);
+
+ /*
+ * skip_fd must be an ordered array of distinct fds, exclude
+ * excluded_fd if already included in the [STDIN_FILENO - STDERR_FILENO]
+ * range
+ */
+ if (excluded_fd <= STDERR_FILENO) {
+ nskip--;
+ }
+
+ qemu_close_all_open_fd(skip_fd, nskip);
+}
+
static void launch_script(const char *setup_script, const char *ifname,
int fd, Error **errp)
{
@@ -400,13 +418,7 @@
return;
}
if (pid == 0) {
- int open_max = sysconf(_SC_OPEN_MAX), i;
-
- for (i = 3; i < open_max; i++) {
- if (i != fd) {
- close(i);
- }
- }
+ close_all_fds_after_fork(fd);
parg = args;
*parg++ = (char *)setup_script;
*parg++ = (char *)ifname;
@@ -490,17 +502,11 @@
return -1;
}
if (pid == 0) {
- int open_max = sysconf(_SC_OPEN_MAX), i;
char *fd_buf = NULL;
char *br_buf = NULL;
char *helper_cmd = NULL;
- for (i = 3; i < open_max; i++) {
- if (i != sv[1]) {
- close(i);
- }
- }
-
+ close_all_fds_after_fork(sv[1]);
fd_buf = g_strdup_printf("%s%d", "--fd=", sv[1]);
if (strrchr(helper, ' ') || strrchr(helper, '\t')) {
diff --git a/system/async-teardown.c b/system/async-teardown.c
index 396963c..9148ee8 100644
--- a/system/async-teardown.c
+++ b/system/async-teardown.c
@@ -26,40 +26,6 @@
static pid_t the_ppid;
-/*
- * Close all open file descriptors.
- */
-static void close_all_open_fd(void)
-{
- struct dirent *de;
- int fd, dfd;
- DIR *dir;
-
-#ifdef CONFIG_CLOSE_RANGE
- int r = close_range(0, ~0U, 0);
- if (!r) {
- /* Success, no need to try other ways. */
- return;
- }
-#endif
-
- dir = opendir("/proc/self/fd");
- if (!dir) {
- /* If /proc is not mounted, there is nothing that can be done. */
- return;
- }
- /* Avoid closing the directory. */
- dfd = dirfd(dir);
-
- for (de = readdir(dir); de; de = readdir(dir)) {
- fd = atoi(de->d_name);
- if (fd != dfd) {
- close(fd);
- }
- }
- closedir(dir);
-}
-
static void hup_handler(int signal)
{
/* Check every second if this process has been reparented. */
@@ -85,9 +51,8 @@
/*
* Close all file descriptors that might have been inherited from the
* main qemu process when doing clone, needed to make libvirt happy.
- * Not using close_range for increased compatibility with older kernels.
*/
- close_all_open_fd();
+ qemu_close_all_open_fd(NULL, 0);
/* Set up a handler for SIGHUP and unblock SIGHUP. */
sigaction(SIGHUP, &sa, NULL);
diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index b090fe0..11b35e4 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -807,3 +807,127 @@
return msync(addr, length, MS_SYNC);
}
+
+static bool qemu_close_all_open_fd_proc(const int *skip, unsigned int nskip)
+{
+ struct dirent *de;
+ int fd, dfd;
+ DIR *dir;
+ unsigned int skip_start = 0, skip_end = nskip;
+
+ dir = opendir("/proc/self/fd");
+ if (!dir) {
+ /* If /proc is not mounted, there is nothing that can be done. */
+ return false;
+ }
+ /* Avoid closing the directory. */
+ dfd = dirfd(dir);
+
+ for (de = readdir(dir); de; de = readdir(dir)) {
+ bool close_fd = true;
+
+ if (de->d_name[0] == '.') {
+ continue;
+ }
+ fd = atoi(de->d_name);
+ if (fd == dfd) {
+ continue;
+ }
+
+ for (unsigned int i = skip_start; i < skip_end; i++) {
+ if (fd < skip[i]) {
+ /* We are below the next skipped fd, break */
+ break;
+ } else if (fd == skip[i]) {
+ close_fd = false;
+ /* Restrict the range as we found fds matching start/end */
+ if (i == skip_start) {
+ skip_start++;
+ } else if (i == skip_end) {
+ skip_end--;
+ }
+ break;
+ }
+ }
+
+ if (close_fd) {
+ close(fd);
+ }
+ }
+ closedir(dir);
+
+ return true;
+}
+
+static bool qemu_close_all_open_fd_close_range(const int *skip,
+ unsigned int nskip,
+ int open_max)
+{
+#ifdef CONFIG_CLOSE_RANGE
+ int max_fd = open_max - 1;
+ int first = 0, last;
+ unsigned int cur_skip = 0;
+ int ret;
+
+ do {
+ /* Find the start boundary of the range to close */
+ while (cur_skip < nskip && first == skip[cur_skip]) {
+ cur_skip++;
+ first++;
+ }
+
+ /* Find the upper boundary of the range to close */
+ last = max_fd;
+ if (cur_skip < nskip) {
+ last = skip[cur_skip] - 1;
+ last = MIN(last, max_fd);
+ }
+
+ /* With the adjustments to the range, we might be done. */
+ if (first > last) {
+ break;
+ }
+
+ ret = close_range(first, last, 0);
+ if (ret < 0) {
+ return false;
+ }
+
+ first = last + 1;
+ } while (last < max_fd);
+
+ return true;
+#else
+ return false;
+#endif
+}
+
+static void qemu_close_all_open_fd_fallback(const int *skip, unsigned int nskip,
+ int open_max)
+{
+ unsigned int cur_skip = 0;
+
+ /* Fallback */
+ for (int i = 0; i < open_max; i++) {
+ if (cur_skip < nskip && i == skip[cur_skip]) {
+ cur_skip++;
+ continue;
+ }
+ close(i);
+ }
+}
+
+/*
+ * Close all open file descriptors.
+ */
+void qemu_close_all_open_fd(const int *skip, unsigned int nskip)
+{
+ int open_max = sysconf(_SC_OPEN_MAX);
+
+ assert(skip != NULL || nskip == 0);
+
+ if (!qemu_close_all_open_fd_close_range(skip, nskip, open_max) &&
+ !qemu_close_all_open_fd_proc(skip, nskip)) {
+ qemu_close_all_open_fd_fallback(skip, nskip, open_max);
+ }
+}
