From 2c80c4f0d2845645f41cbb7c9304c8efbdbd4331 Mon Sep 17 00:00:00 2001 From: Jai Luthra Date: Fri, 1 Sep 2023 15:01:23 +0530 Subject: [PATCH] drm: bridge: it66121: Fix invalid connector dereference [ Upstream commit d0375f6858c4ff7244b62b02eb5e93428e1916cd ] Fix the NULL pointer dereference when no monitor is connected, and the sound card is opened from userspace. Instead return an empty buffer (of zeroes) as the EDID information to the sound framework if there is no connector attached. Fixes: e0fd83dbe924 ("drm: bridge: it66121: Add audio support") Reported-by: Nishanth Menon Closes: https://lore.kernel.org/all/20230825105849.crhon42qndxqif4i@gondola/ Reviewed-by: Helen Koike Signed-off-by: Jai Luthra Tested-by: Nishanth Menon Reviewed-by: Aradhya Bhatia Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20230901-it66121_edid-v2-1-aa59605336b9@ti.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/bridge/ite-it66121.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/bridge/ite-it66121.c b/drivers/gpu/drm/bridge/ite-it66121.c index 4f6f1deba28c..9d7f3c99748b 100644 --- a/drivers/gpu/drm/bridge/ite-it66121.c +++ b/drivers/gpu/drm/bridge/ite-it66121.c @@ -1464,10 +1464,14 @@ static int it66121_audio_get_eld(struct device *dev, void *data, struct it66121_ctx *ctx = dev_get_drvdata(dev); mutex_lock(&ctx->lock); - - memcpy(buf, ctx->connector->eld, - min(sizeof(ctx->connector->eld), len)); - + if (!ctx->connector) { + /* Pass en empty ELD if connector not available */ + dev_dbg(dev, "No connector present, passing empty EDID data"); + memset(buf, 0, len); + } else { + memcpy(buf, ctx->connector->eld, + min(sizeof(ctx->connector->eld), len)); + } mutex_unlock(&ctx->lock); return 0; -- 2.34.1