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| author | Kees Cook <kees+treewide@kernel.org> | 2026-09-02 15:31:14 -0700 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2026-09-04 21:37:00 -0700 |
| commit | 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch) | |
| tree | c65086f9bdcd48c6360fb7cb4598bca084da1f32 /samples/hid/hid_mouse.bpf.c | |
| download | linux-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/hid/hid_mouse.bpf.c')
| -rw-r--r-- | samples/hid/hid_mouse.bpf.c | 128 |
1 files changed, 128 insertions, 0 deletions
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"; |
