From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 ED4DA43C7A2; Thu, 30 Jul 2026 15:22:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424981; cv=none; b=LrDAnOt6uGvUtRliGIwgOF58yAgwBvgq6oNSBJC6IPMo1pl4Y4JTNUK22bICR04Eqa6emaZ0wv5wmQsQGsl8oLnn4WC0CvDQs9VUjE89/t4MOxpmu2wjKIAaJSbapldT1fNZfgukdrzukbCacK3y/m/vDCPymqRZBgq/QnS+G/8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424981; c=relaxed/simple; bh=h+3sDjVRQkK3EB/aNOzUfmaEb2b1n84wZZpYdH2XhBY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RRJbkPXg636ClL+RBosqylBJRta7faJwQVJmrEYdg3NM+xcYGEjoRlrGtBBu9gD54JozkpG0nXmOmxwKrbcpC4Ip0wXAPSMuEKcGjl0C1kyZUVmqpaWLtJK1ba71jib3d6nrqpyA4VdWHvPmFHucXdVDk1AjD5QaPgys2z8HXSA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MkAMbhav; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="MkAMbhav" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4690A1F000E9; Thu, 30 Jul 2026 15:22:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785424979; bh=QTXLSauxTb3Fsxbyxcwgm11tj4tqsMKZe01prHh9xVM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MkAMbhav088k92METNFY/ob34GxEjmwCwC3SfCsjI3rclUDWz1X20e5Iwy590rMZ3 2Rs/2yHePv9iAgwU0Yi13CcltujOs+sDXjN30Lj9Dac+dgKdkoYzMxJezq1OzoQNLw gOxgl/Ht20HWfunXf5QlyHKtlECd6SIp7uhtAHiA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Boyuan Zhang , David Rosca , Alex Deucher Subject: [PATCH 6.18 583/675] drm/amdgpu/vcn4: avoid rereading IB param length Date: Thu, 30 Jul 2026 16:15:13 +0200 Message-ID: <20260730141457.514877447@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@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: Boyuan Zhang commit 3b4082fabc67c9780b06eb959e59dd92fa79c0f0 upstream. Reuse the parameter length returned by vcn_v4_0_enc_find_ib_param() instead of rereading it from the IB. This avoids a potential TOCTOU issue if the IB contents change between reads. Signed-off-by: Boyuan Zhang Reviewed-by: David Rosca Signed-off-by: Alex Deucher (cherry picked from commit dbb02b4755f8c1f3773263f2d779872c1c0c073a) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) --- a/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c +++ b/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c @@ -1926,14 +1926,17 @@ out: #define RENCODE_IB_PARAM_SESSION_INIT 0x00000003 /* return the offset in ib if id is found, -1 otherwise */ -static int vcn_v4_0_enc_find_ib_param(struct amdgpu_ib *ib, uint32_t id, int start) +static int vcn_v4_0_enc_find_ib_param(struct amdgpu_ib *ib, uint32_t id, int start, uint32_t *length) { int i; uint32_t len; for (i = start; (len = amdgpu_ib_get_value(ib, i)) >= 8; i += len / 4) { - if (amdgpu_ib_get_value(ib, i + 1) == id) + if (amdgpu_ib_get_value(ib, i + 1) == id) { + if (length) + *length = len; return i; + } } return -1; } @@ -1943,14 +1946,14 @@ static int vcn_v4_0_ring_patch_cs_in_pla struct amdgpu_ib *ib) { struct amdgpu_ring *ring = amdgpu_job_ring(job); - uint32_t val; + uint32_t val, len; int idx = 0, sidx; /* The first instance can decode anything */ if (!ring->me) return 0; - while ((idx = vcn_v4_0_enc_find_ib_param(ib, RADEON_VCN_ENGINE_INFO, idx)) >= 0) { + while ((idx = vcn_v4_0_enc_find_ib_param(ib, RADEON_VCN_ENGINE_INFO, idx, &len)) >= 0) { val = amdgpu_ib_get_value(ib, idx + 2); /* RADEON_VCN_ENGINE_TYPE */ if (val == RADEON_VCN_ENGINE_TYPE_DECODE) { uint32_t valid_buf_flag = amdgpu_ib_get_value(ib, idx + 6); @@ -1963,12 +1966,12 @@ static int vcn_v4_0_ring_patch_cs_in_pla amdgpu_ib_get_value(ib, idx + 8); return vcn_v4_0_dec_msg(p, job, msg_buffer_addr); } else if (val == RADEON_VCN_ENGINE_TYPE_ENCODE) { - sidx = vcn_v4_0_enc_find_ib_param(ib, RENCODE_IB_PARAM_SESSION_INIT, idx); + sidx = vcn_v4_0_enc_find_ib_param(ib, RENCODE_IB_PARAM_SESSION_INIT, idx, NULL); if (sidx >= 0 && amdgpu_ib_get_value(ib, sidx + 2) == RENCODE_ENCODE_STANDARD_AV1) return vcn_v4_0_limit_sched(p, job); } - idx += amdgpu_ib_get_value(ib, idx) / 4; + idx += len / 4; } return 0; }