From 04feb58d811be27c92745442497ea5c96999f38f Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Mon, 8 Oct 2018 15:08:27 -0400 Subject: [PATCH] media: v4l2-tpg: fix kernel oops when enabling HFLIP and OSD commit 250854eed5d45a73d81e4137dfd85180af6f2ec3 upstream. When the OSD is on (i.e. vivid displays text on top of the test pattern), and you enable hflip, then the driver crashes. The cause turned out to be a division of a negative number by an unsigned value. You expect that -8 / 2U would be -4, but in reality it is 2147483644 :-( Fixes: 3e14e7a82c1ef ("vivid-tpg: add hor/vert downsampling support to tpg_gen_text") Signed-off-by: Hans Verkuil Reported-by: Mauro Carvalho Chehab Cc: # for v4.1 and up Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/common/v4l2-tpg/v4l2-tpg-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c index abd4c78..f40ab57 100644 --- a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c +++ b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c @@ -1770,7 +1770,7 @@ typedef struct { u16 __; u8 _; } __packed x24; pos[7] = (chr & (0x01 << 0) ? fg : bg); \ } \ \ - pos += (tpg->hflip ? -8 : 8) / hdiv; \ + pos += (tpg->hflip ? -8 : 8) / (int)hdiv; \ } \ } \ } while (0) -- 2.7.4