From 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d Mon Sep 17 00:00:00 2001
From: Kees Cook <kees+treewide@kernel.org>
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 <kees+treewide@kernel.org>
---
 samples/hid/hid_mouse.bpf.c | 128 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 128 insertions(+)
 create mode 100644 samples/hid/hid_mouse.bpf.c

(limited to 'samples/hid/hid_mouse.bpf.c')

diff --git a/samples/hid/hid_mouse.bpf.c b/samples/hid/hid_mouse.bpf.c
new file mode 100644
index 000000000..f7f722dcf
--- /dev/null
+++ b/samples/hid/hid_mouse.bpf.c
@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include "hid_bpf_helpers.h"
+
+static int hid_y_event(struct hid_bpf_ctx *hctx)
+{
+	s16 y;
+	__u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 9 /* size */);
+
+	if (!data)
+		return 0; /* EPERM check */
+
+	bpf_printk("event: size: %d", hctx->size);
+	bpf_printk("incoming event: %02x %02x %02x",
+		   data[0],
+		   data[1],
+		   data[2]);
+	bpf_printk("                %02x %02x %02x",
+		   data[3],
+		   data[4],
+		   data[5]);
+	bpf_printk("                %02x %02x %02x",
+		   data[6],
+		   data[7],
+		   data[8]);
+
+	y = data[3] | (data[4] << 8);
+
+	y = -y;
+
+	data[3] = y & 0xFF;
+	data[4] = (y >> 8) & 0xFF;
+
+	bpf_printk("modified event: %02x %02x %02x",
+		   data[0],
+		   data[1],
+		   data[2]);
+	bpf_printk("                %02x %02x %02x",
+		   data[3],
+		   data[4],
+		   data[5]);
+	bpf_printk("                %02x %02x %02x",
+		   data[6],
+		   data[7],
+		   data[8]);
+
+	return 0;
+}
+
+static int hid_x_event(struct hid_bpf_ctx *hctx)
+{
+	s16 x;
+	__u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 9 /* size */);
+
+	if (!data)
+		return 0; /* EPERM check */
+
+	x = data[1] | (data[2] << 8);
+
+	x = -x;
+
+	data[1] = x & 0xFF;
+	data[2] = (x >> 8) & 0xFF;
+	return 0;
+}
+
+SEC("struct_ops/hid_device_event")
+int BPF_PROG(hid_event, struct hid_bpf_ctx *hctx, enum hid_report_type type)
+{
+	int ret = hid_y_event(hctx);
+
+	if (ret)
+		return ret;
+
+	return hid_x_event(hctx);
+}
+
+
+SEC("struct_ops/hid_rdesc_fixup")
+int BPF_PROG(hid_rdesc_fixup, struct hid_bpf_ctx *hctx)
+{
+	__u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 4096 /* size */);
+
+	if (!data)
+		return 0; /* EPERM check */
+
+	bpf_printk("rdesc: %02x %02x %02x",
+		   data[0],
+		   data[1],
+		   data[2]);
+	bpf_printk("       %02x %02x %02x",
+		   data[3],
+		   data[4],
+		   data[5]);
+	bpf_printk("       %02x %02x %02x ...",
+		   data[6],
+		   data[7],
+		   data[8]);
+
+	/*
+	 * The original report descriptor contains:
+	 *
+	 * 0x05, 0x01,                    //   Usage Page (Generic Desktop)      30
+	 * 0x16, 0x01, 0x80,              //   Logical Minimum (-32767)          32
+	 * 0x26, 0xff, 0x7f,              //   Logical Maximum (32767)           35
+	 * 0x09, 0x30,                    //   Usage (X)                         38
+	 * 0x09, 0x31,                    //   Usage (Y)                         40
+	 *
+	 * So byte 39 contains Usage X and byte 41 Usage Y.
+	 *
+	 * We simply swap the axes here.
+	 */
+	data[39] = 0x31;
+	data[41] = 0x30;
+
+	return 0;
+}
+
+SEC(".struct_ops.link")
+struct hid_bpf_ops mouse_invert = {
+	.hid_rdesc_fixup = (void *)hid_rdesc_fixup,
+	.hid_device_event = (void *)hid_event,
+};
+
+char _license[] SEC("license") = "GPL";
-- 
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