From 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 2 Sep 2026 15:31:14 -0700 Subject: treewide: refresh kmalloc_obj() conversions 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 --- tools/perf/util/cloexec.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 tools/perf/util/cloexec.c (limited to 'tools/perf/util/cloexec.c') 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 +#include +#include "util.h" // for sched_getcpu() +#include "../perf-sys.h" +#include "cloexec.h" +#include "event.h" +#include "asm/bug.h" +#include "debug.h" +#include +#include +#include + +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; +} -- cgit v1.3.1