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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /tools/perf/util/cloexec.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'tools/perf/util/cloexec.c')
-rw-r--r--tools/perf/util/cloexec.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/tools/perf/util/cloexec.c b/tools/perf/util/cloexec.c
new file mode 100644
index 000000000..8830604c3
--- /dev/null
+++ b/tools/perf/util/cloexec.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <errno.h>
+#include <sched.h>
+#include "util.h" // for sched_getcpu()
+#include "../perf-sys.h"
+#include "cloexec.h"
+#include "event.h"
+#include "asm/bug.h"
+#include "debug.h"
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <linux/string.h>
+
+static unsigned long flag = PERF_FLAG_FD_CLOEXEC;
+
+static int perf_flag_probe(void)
+{
+ /* use 'safest' configuration as used in evsel__fallback() */
+ struct perf_event_attr attr = {
+ .type = PERF_TYPE_SOFTWARE,
+ .config = PERF_COUNT_SW_CPU_CLOCK,
+ .exclude_kernel = 1,
+ };
+ int fd;
+ int err;
+ int cpu;
+ pid_t pid = -1;
+ char sbuf[STRERR_BUFSIZE];
+
+ cpu = sched_getcpu();
+ if (cpu < 0)
+ cpu = 0;
+
+ /*
+ * Using -1 for the pid is a workaround to avoid gratuitous jump label
+ * changes.
+ */
+ while (1) {
+ /* check cloexec flag */
+ fd = sys_perf_event_open(&attr, pid, cpu, -1,
+ PERF_FLAG_FD_CLOEXEC);
+ if (fd < 0 && pid == -1 && errno == EACCES) {
+ pid = 0;
+ continue;
+ }
+ break;
+ }
+ err = errno;
+
+ if (fd >= 0) {
+ close(fd);
+ return 1;
+ }
+
+ WARN_ONCE(err != EINVAL && err != EBUSY && err != EACCES,
+ "perf_event_open(..., PERF_FLAG_FD_CLOEXEC) failed with unexpected error %d (%s)\n",
+ err, str_error_r(err, sbuf, sizeof(sbuf)));
+
+ /* not supported, confirm error related to PERF_FLAG_FD_CLOEXEC */
+ while (1) {
+ fd = sys_perf_event_open(&attr, pid, cpu, -1, 0);
+ if (fd < 0 && pid == -1 && errno == EACCES) {
+ pid = 0;
+ continue;
+ }
+ break;
+ }
+ err = errno;
+
+ if (fd >= 0)
+ close(fd);
+
+ if (WARN_ONCE(fd < 0 && err != EBUSY && err != EACCES,
+ "perf_event_open(..., 0) failed unexpectedly with error %d (%s)\n",
+ err, str_error_r(err, sbuf, sizeof(sbuf))))
+ return -1;
+
+ return 0;
+}
+
+unsigned long perf_event_open_cloexec_flag(void)
+{
+ static bool probed;
+
+ if (!probed) {
+ if (perf_flag_probe() <= 0)
+ flag = 0;
+ probed = true;
+ }
+
+ return flag;
+}