linux-kernel - [PATCH 2/2] media: vidtv: remove an impossible condition

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Date:   Thu, 17 Sep 2020 11:51:36 +0200
From:   Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
To:     unlisted-recipients:; (no To-header on input)
Cc:     Mauro Carvalho Chehab <mchehab+huawei@...nel.org>,
        "Daniel W. S. Almeida" <dwlsalmeida@...il.com>,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        linux-kernel@...r.kernel.org, linux-media@...r.kernel.org
Subject: [PATCH 2/2] media: vidtv: remove an impossible condition

As warned by smatch:

	drivers/media/test-drivers/vidtv/vidtv_psi.c:93 vidtv_psi_update_version_num() warn: impossible condition '(h->version > 32) => (0-31 > 32)'

h_version is declared as:

		u8  version:5;

Meaning that its value ranges from 0 to 31. Incrementing 31 on such
data will overflow to zero, as expected.

So, just drop the uneeded overflow check.

While here, use "foo++" instead of "++foo", as this is a much
more common pattern.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
---
 drivers/media/test-drivers/vidtv/vidtv_psi.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/media/test-drivers/vidtv/vidtv_psi.c b/drivers/media/test-drivers/vidtv/vidtv_psi.c
index b8b638244b1d..8cdf645b4fdd 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_psi.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_psi.c
@@ -89,9 +89,7 @@ static inline u32 dvb_crc32(u32 crc, u8 *data, u32 len)
 
 static void vidtv_psi_update_version_num(struct vidtv_psi_table_header *h)
 {
-	++h->version;
-	if (h->version > MAX_VERSION_NUM)
-		h->version = 0;
+	h->version++;
 }
 
 static inline u16 vidtv_psi_sdt_serv_get_desc_loop_len(struct vidtv_psi_table_sdt_service *s)
-- 
2.26.2