From: Hans Verkuil Date: Mon, 8 Oct 2018 19:08:27 +0000 (-0400) Subject: media: v4l2-tpg: fix kernel oops when enabling HFLIP and OSD X-Git-Tag: v4.9.137~25 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c40015f3f3389232b22cbb98ea679d42a5604188;p=platform%2Fkernel%2Flinux-amlogic.git 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 --- diff --git a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c index 1684810cab83..1f463f4c3024 100644 --- a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c +++ b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c @@ -1650,7 +1650,7 @@ 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)