From bdf606810210e8e07a0cdf1af3c467291363b295 Mon Sep 17 00:00:00 2001 From: Srinivasan Shanmugam Date: Fri, 19 Jul 2024 21:39:57 +0530 Subject: [PATCH] drm/amd/display: Implement bounds check for stream encoder creation in DCN401 'stream_enc_regs' array is an array of dcn10_stream_enc_registers structures. The array is initialized with four elements, corresponding to the four calls to stream_enc_regs() in the array initializer. This means that valid indices for this array are 0, 1, 2, and 3. The error message 'stream_enc_regs' 4 <= 5 below, is indicating that there is an attempt to access this array with an index of 5, which is out of bounds. This could lead to undefined behavior Here, eng_id is used as an index to access the stream_enc_regs array. If eng_id is 5, this would result in an out-of-bounds access on the stream_enc_regs array. Thus fixing Buffer overflow error in dcn401_stream_encoder_create Found by smatch: drivers/gpu/drm/amd/amdgpu/../display/dc/resource/dcn401/dcn401_resource.c:1209 dcn401_stream_encoder_create() error: buffer overflow 'stream_enc_regs' 4 <= 5 Cc: Tom Chung Cc: Rodrigo Siqueira Cc: Roman Li Cc: Alex Hung Cc: Aurabindo Pillai Cc: Harry Wentland Cc: Hamza Mahfooz Signed-off-by: Srinivasan Shanmugam Reviewed-by: Tom Chung Signed-off-by: Alex Deucher --- .../gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c index d3808c49d298..5ee20753572e 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c @@ -1190,7 +1190,7 @@ static struct stream_encoder *dcn401_stream_encoder_create( vpg = dcn401_vpg_create(ctx, vpg_inst); afmt = dcn401_afmt_create(ctx, afmt_inst); - if (!enc1 || !vpg || !afmt) { + if (!enc1 || !vpg || !afmt || eng_id >= ARRAY_SIZE(stream_enc_regs)) { kfree(enc1); kfree(vpg); kfree(afmt);