summaryrefslogtreecommitdiffstats
path: root/samples/user_events
diff options
context:
space:
mode:
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 /samples/user_events
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 'samples/user_events')
-rw-r--r--samples/user_events/Makefile5
-rw-r--r--samples/user_events/example.c73
2 files changed, 78 insertions, 0 deletions
diff --git a/samples/user_events/Makefile b/samples/user_events/Makefile
new file mode 100644
index 000000000..7252b589d
--- /dev/null
+++ b/samples/user_events/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+CFLAGS += -Wl,-no-as-needed -Wall -I../../usr/include
+
+example: example.o
+example.o: example.c
diff --git a/samples/user_events/example.c b/samples/user_events/example.c
new file mode 100644
index 000000000..28165a096
--- /dev/null
+++ b/samples/user_events/example.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021, Microsoft Corporation.
+ *
+ * Authors:
+ * Beau Belgrave <beaub@linux.microsoft.com>
+ */
+
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/uio.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <linux/user_events.h>
+
+const char *data_file = "/sys/kernel/tracing/user_events_data";
+int enabled = 0;
+
+static int event_reg(int fd, const char *command, int *write, int *enabled)
+{
+ struct user_reg reg = {0};
+
+ reg.size = sizeof(reg);
+ reg.enable_bit = 31;
+ reg.enable_size = sizeof(*enabled);
+ reg.enable_addr = (__u64)enabled;
+ reg.name_args = (__u64)command;
+
+ if (ioctl(fd, DIAG_IOCSREG, &reg) == -1)
+ return -1;
+
+ *write = reg.write_index;
+
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ int data_fd, write;
+ struct iovec io[2];
+ __u32 count = 0;
+
+ data_fd = open(data_file, O_RDWR);
+
+ if (event_reg(data_fd, "test u32 count", &write, &enabled) == -1)
+ return errno;
+
+ /* Setup iovec */
+ io[0].iov_base = &write;
+ io[0].iov_len = sizeof(write);
+ io[1].iov_base = &count;
+ io[1].iov_len = sizeof(count);
+ask:
+ printf("Press enter to check status...\n");
+ getchar();
+
+ /* Check if anyone is listening */
+ if (enabled) {
+ /* Yep, trace out our data */
+ writev(data_fd, (const struct iovec *)io, 2);
+
+ /* Increase the count */
+ count++;
+
+ printf("Something was attached, wrote data\n");
+ }
+
+ goto ask;
+
+ return 0;
+}