Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 86E242BDC03; Wed, 25 Feb 2026 06:59:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772002762; cv=none; b=lydmyC6TTQZeD59B4c5EF4RsZJ5NHJPen8fAG8oo+Kh6c1EHLQxfIdwPKcQdlWjlW4OyjA4GQ4c5Aq5msqHZ3PNUhRDRTJhKn1G3efu5h0jtxMoOMaVQng0rfLfmNAyNE4wblECe7GGBArjtr0CaAeRGNBfTtDAfrsPa7JXH4h4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772002762; c=relaxed/simple; bh=6sfTjFsDe9Kwf/spSj65jT1JEboyrSD8Clqk29LAc6Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fGIr747VF4CuUjQczS65zSuRjQDC7Tiq7F2uQvHZCpFLqG2WRYmC19ywNBPAH/C6aAcj61iGJqSMfQxGppZIFViPf7y13w2hhFOeia2EJN4PXh4cXKdkyG3llRaKhHYP/ojIGyAHgHrJNiLM0DZdekSxBWWfOrIy7FD0j1Li1B8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zARMqQt2; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zARMqQt2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A854C116D0; Wed, 25 Feb 2026 06:59:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1772002762; bh=6sfTjFsDe9Kwf/spSj65jT1JEboyrSD8Clqk29LAc6Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zARMqQt2Hs3K9LRnIG2FlamWfV1tOwbm001apLvddlj4/Lyg6XicyJd5/pxwMAuMa zaofMKIePKrNkAA855UT4wMMonkG8C0FFYbMPeCzQkp9eAFMxZjj+5q/ad6iFIjVHx FYDEa0wVMmYKTCW9e+Puon5UEblav+TtT0gIDJkE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dan Carpenter , Harry Wentland , Mario Limonciello , Alex Hung , Aurabindo Pillai , ChiaHsuan Chung , Roman Li , Srinivasan Shanmugam , Alex Deucher , Sasha Levin Subject: [PATCH 6.18 592/641] drm/amd/display: Fix out-of-bounds stream encoder index v3 Date: Tue, 24 Feb 2026 17:25:18 -0800 Message-ID: <20260225012402.859255091@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260225012348.915798704@linuxfoundation.org> References: <20260225012348.915798704@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Srinivasan Shanmugam [ Upstream commit abde491143e4e12eecc41337910aace4e8d59603 ] eng_id can be negative and that stream_enc_regs[] can be indexed out of bounds. eng_id is used directly as an index into stream_enc_regs[], which has only 5 entries. When eng_id is 5 (ENGINE_ID_DIGF) or negative, this can access memory past the end of the array. Add a bounds check using ARRAY_SIZE() before using eng_id as an index. The unsigned cast also rejects negative values. This avoids out-of-bounds access. Fixes the below smatch error: dcn*_resource.c: stream_encoder_create() may index stream_enc_regs[eng_id] out of bounds (size 5). drivers/gpu/drm/amd/amdgpu/../display/dc/resource/dcn351/dcn351_resource.c 1246 static struct stream_encoder *dcn35_stream_encoder_create( 1247 enum engine_id eng_id, 1248 struct dc_context *ctx) 1249 { ... 1255 1256 /* Mapping of VPG, AFMT, DME register blocks to DIO block instance */ 1257 if (eng_id <= ENGINE_ID_DIGF) { ENGINE_ID_DIGF is 5. should <= be dc_bios, 1283 eng_id, vpg, afmt, --> 1284 &stream_enc_regs[eng_id], ^^^^^^^^^^^^^^^^^^^^^^^ This stream_enc_regs[] array has 5 elements so we are one element beyond the end of the array. ... 1287 return &enc1->base; 1288 } v2: use explicit bounds check as suggested by Roman/Dan; avoid unsigned int cast v3: The compiler already knows how to compare the two values, so the cast (int) is not needed. (Roman) Fixes: 2728e9c7c842 ("drm/amd/display: add DC changes for DCN351") Reported-by: Dan Carpenter Cc: Harry Wentland Cc: Mario Limonciello Cc: Alex Hung Cc: Aurabindo Pillai Cc: ChiaHsuan Chung Cc: Roman Li Signed-off-by: Srinivasan Shanmugam Reviewed-by: Roman Li Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- .../drm/amd/display/dc/resource/dcn315/dcn315_resource.c | 8 ++++---- .../drm/amd/display/dc/resource/dcn316/dcn316_resource.c | 8 ++++---- .../drm/amd/display/dc/resource/dcn32/dcn32_resource.c | 8 ++++---- .../drm/amd/display/dc/resource/dcn321/dcn321_resource.c | 8 ++++---- .../drm/amd/display/dc/resource/dcn35/dcn35_resource.c | 8 ++++---- .../drm/amd/display/dc/resource/dcn351/dcn351_resource.c | 8 ++++---- 6 files changed, 24 insertions(+), 24 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn315/dcn315_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn315/dcn315_resource.c index 82cc78c291d82..12c2a0d9fb2a3 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn315/dcn315_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn315/dcn315_resource.c @@ -1226,12 +1226,12 @@ static struct stream_encoder *dcn315_stream_encoder_create( /*PHYB is wired off in HW, allow front end to remapping, otherwise needs more changes*/ /* Mapping of VPG, AFMT, DME register blocks to DIO block instance */ - if (eng_id <= ENGINE_ID_DIGF) { - vpg_inst = eng_id; - afmt_inst = eng_id; - } else + if (eng_id < 0 || eng_id >= ARRAY_SIZE(stream_enc_regs)) return NULL; + vpg_inst = eng_id; + afmt_inst = eng_id; + enc1 = kzalloc(sizeof(struct dcn10_stream_encoder), GFP_KERNEL); vpg = dcn31_vpg_create(ctx, vpg_inst); afmt = dcn31_afmt_create(ctx, afmt_inst); diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn316/dcn316_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn316/dcn316_resource.c index 636110e48d01b..3c77c14c5a5ed 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn316/dcn316_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn316/dcn316_resource.c @@ -1220,12 +1220,12 @@ static struct stream_encoder *dcn316_stream_encoder_create( int afmt_inst; /* Mapping of VPG, AFMT, DME register blocks to DIO block instance */ - if (eng_id <= ENGINE_ID_DIGF) { - vpg_inst = eng_id; - afmt_inst = eng_id; - } else + if (eng_id < 0 || eng_id >= ARRAY_SIZE(stream_enc_regs)) return NULL; + vpg_inst = eng_id; + afmt_inst = eng_id; + enc1 = kzalloc(sizeof(struct dcn10_stream_encoder), GFP_KERNEL); vpg = dcn31_vpg_create(ctx, vpg_inst); afmt = dcn31_afmt_create(ctx, afmt_inst); diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c index 3965a7f1b64b7..9cace432ce364 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c @@ -1208,12 +1208,12 @@ static struct stream_encoder *dcn32_stream_encoder_create( int afmt_inst; /* Mapping of VPG, AFMT, DME register blocks to DIO block instance */ - if (eng_id <= ENGINE_ID_DIGF) { - vpg_inst = eng_id; - afmt_inst = eng_id; - } else + if (eng_id < 0 || eng_id >= ARRAY_SIZE(stream_enc_regs)) return NULL; + vpg_inst = eng_id; + afmt_inst = eng_id; + enc1 = kzalloc(sizeof(struct dcn10_stream_encoder), GFP_KERNEL); vpg = dcn32_vpg_create(ctx, vpg_inst); afmt = dcn32_afmt_create(ctx, afmt_inst); diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn321/dcn321_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn321/dcn321_resource.c index ad214986f7ac7..26fd5c03c0147 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn321/dcn321_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn321/dcn321_resource.c @@ -1189,12 +1189,12 @@ static struct stream_encoder *dcn321_stream_encoder_create( int afmt_inst; /* Mapping of VPG, AFMT, DME register blocks to DIO block instance */ - if (eng_id <= ENGINE_ID_DIGF) { - vpg_inst = eng_id; - afmt_inst = eng_id; - } else + if (eng_id < 0 || eng_id >= ARRAY_SIZE(stream_enc_regs)) return NULL; + vpg_inst = eng_id; + afmt_inst = eng_id; + enc1 = kzalloc(sizeof(struct dcn10_stream_encoder), GFP_KERNEL); vpg = dcn321_vpg_create(ctx, vpg_inst); afmt = dcn321_afmt_create(ctx, afmt_inst); diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c index 06bec7dcc7556..e8d74ceb9dc29 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c @@ -1271,12 +1271,12 @@ static struct stream_encoder *dcn35_stream_encoder_create( int afmt_inst; /* Mapping of VPG, AFMT, DME register blocks to DIO block instance */ - if (eng_id <= ENGINE_ID_DIGF) { - vpg_inst = eng_id; - afmt_inst = eng_id; - } else + if (eng_id < 0 || eng_id >= ARRAY_SIZE(stream_enc_regs)) return NULL; + vpg_inst = eng_id; + afmt_inst = eng_id; + enc1 = kzalloc(sizeof(struct dcn10_stream_encoder), GFP_KERNEL); vpg = dcn31_vpg_create(ctx, vpg_inst); afmt = dcn31_afmt_create(ctx, afmt_inst); diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c index 7974e306126e0..532e5d9bc4337 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c @@ -1251,12 +1251,12 @@ static struct stream_encoder *dcn35_stream_encoder_create( int afmt_inst; /* Mapping of VPG, AFMT, DME register blocks to DIO block instance */ - if (eng_id <= ENGINE_ID_DIGF) { - vpg_inst = eng_id; - afmt_inst = eng_id; - } else + if (eng_id < 0 || eng_id >= ARRAY_SIZE(stream_enc_regs)) return NULL; + vpg_inst = eng_id; + afmt_inst = eng_id; + enc1 = kzalloc(sizeof(struct dcn10_stream_encoder), GFP_KERNEL); vpg = dcn31_vpg_create(ctx, vpg_inst); afmt = dcn31_afmt_create(ctx, afmt_inst); -- 2.51.0