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Date: Tue, 26 Dec 2023 19:24:14 +0100
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To: bpf@vger.kernel.org, linux-input@vger.kernel.org,
 kernel-janitors@vger.kernel.org, Alexei Starovoitov <ast@kernel.org>,
 Benjamin Tissoires <benjamin.tissoires@redhat.com>,
 David Vernet <void@manifault.com>, Jiri Kosina <jikos@kernel.org>
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Cc: LKML <linux-kernel@vger.kernel.org>, cocci@inria.fr
From: Markus Elfring <Markus.Elfring@web.de>
Subject: [PATCH] HID: bpf: One function call less in
 call_hid_bpf_rdesc_fixup() after error detection
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 h08qWA==

From: Markus Elfring <elfring@users.sourceforge.net>
Date: Tue, 26 Dec 2023 19:13:25 +0100

The kfree() function was called in one case by the
call_hid_bpf_rdesc_fixup() function during error handling
even if the passed data structure member contained a null pointer.
This issue was detected by using the Coccinelle software.

Thus adjust jump targets.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
=2D--
 drivers/hid/bpf/hid_bpf_dispatch.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/hid/bpf/hid_bpf_dispatch.c b/drivers/hid/bpf/hid_bpf_=
dispatch.c
index d9ef45fcaeab..c84fe55be5ed 100644
=2D-- a/drivers/hid/bpf/hid_bpf_dispatch.c
+++ b/drivers/hid/bpf/hid_bpf_dispatch.c
@@ -118,17 +118,17 @@ u8 *call_hid_bpf_rdesc_fixup(struct hid_device *hdev=
, u8 *rdesc, unsigned int *s

 	ctx_kern.data =3D kzalloc(ctx_kern.ctx.allocated_size, GFP_KERNEL);
 	if (!ctx_kern.data)
-		goto ignore_bpf;
+		goto dup_mem;

 	memcpy(ctx_kern.data, rdesc, min_t(unsigned int, *size, HID_MAX_DESCRIPT=
OR_SIZE));

 	ret =3D hid_bpf_prog_run(hdev, HID_BPF_PROG_TYPE_RDESC_FIXUP, &ctx_kern)=
;
 	if (ret < 0)
-		goto ignore_bpf;
+		goto free_data;

 	if (ret) {
 		if (ret > ctx_kern.ctx.allocated_size)
-			goto ignore_bpf;
+			goto free_data;

 		*size =3D ret;
 	}
@@ -137,8 +137,9 @@ u8 *call_hid_bpf_rdesc_fixup(struct hid_device *hdev, =
u8 *rdesc, unsigned int *s

 	return rdesc;

- ignore_bpf:
+free_data:
 	kfree(ctx_kern.data);
+dup_mem:
 	return kmemdup(rdesc, *size, GFP_KERNEL);
 }
 EXPORT_SYMBOL_GPL(call_hid_bpf_rdesc_fixup);
=2D-
2.43.0