<!DOCTYPE html><html><head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body> <p> </p> <p><span style="mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family: "Times New Roman";mso-bidi-theme-font:minor-bidi;mso-fareast-language:ZH-TW">It looks good to me.<br> </span></p> <p><span style="mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family: "Times New Roman";mso-bidi-theme-font:minor-bidi;mso-fareast-language:ZH-TW">Reviewed-by: Tom Chung <a href="mailto:chiahsuan.chung@amd.com"><chiahsuan.chung@amd.com></a></span></p> <div class="moz-cite-prefix">On 1/30/2024 5:49 PM, SHANMUGAM, SRINIVASAN wrote:<br> </div> <blockquote type="cite" cite="mid:MN2PR12MB41284AEF8A5554E83D0AB307907D2@MN2PR12MB4128.namprd12.prod.outlook.com"> <meta name="Generator" content="Microsoft Word 15 (filtered medium)"> <style>@font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4;}@font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4;}@font-face {font-family:Consolas; panose-1:2 11 6 9 2 2 4 3 2 4;}p.MsoNormal, li.MsoNormal, div.MsoNormal {margin:0in; font-size:11.0pt; font-family:"Calibri",sans-serif;}a:link, span.MsoHyperlink {mso-style-priority:99; color:blue; text-decoration:underline;}p.MsoPlainText, li.MsoPlainText, div.MsoPlainText {mso-style-priority:99; mso-style-link:"Plain Text Char"; mso-margin-top-alt:auto; margin-right:0in; mso-margin-bottom-alt:auto; margin-left:0in; font-size:11.0pt; font-family:"Calibri",sans-serif;}pre {mso-style-priority:99; mso-style-link:"HTML Preformatted Char"; margin:0in; font-size:10.0pt; font-family:"Courier New";}span.PlainTextChar {mso-style-name:"Plain Text Char"; mso-style-priority:99; mso-style-link:"Plain Text"; font-family:Consolas;}span.HTMLPreformattedChar {mso-style-name:"HTML Preformatted Char"; mso-style-priority:99; mso-style-link:"HTML Preformatted"; font-family:Consolas;}span.EmailStyle23 {mso-style-type:personal-reply; font-family:"Calibri",sans-serif; color:windowtext;}.MsoChpDefault {mso-style-type:export-only; font-size:10.0pt; mso-ligatures:none;}div.WordSection1 {page:WordSection1;}</style> <p style="font-family:Arial;font-size:10pt;color:#0000FF;margin:5pt;font-style:normal;font-weight:normal;text-decoration:none;" align="Left"> [AMD Official Use Only - General]<br> </p> <br> <div> <div class="WordSection1"> <p class="MsoNormal"><o:p> </o:p></p> <p class="MsoNormal"><o:p> </o:p></p> <div> <div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in"> <p class="MsoNormal"><b>From:</b> SHANMUGAM, SRINIVASAN <br> <b>Sent:</b> Tuesday, January 30, 2024 3:18 PM<br> <b>To:</b> Siqueira, Rodrigo <a class="moz-txt-link-rfc2396E" href="mailto:Rodrigo.Siqueira@amd.com"><Rodrigo.Siqueira@amd.com></a>; Pillai, Aurabindo <a class="moz-txt-link-rfc2396E" href="mailto:Aurabindo.Pillai@amd.com"><Aurabindo.Pillai@amd.com></a><br> <b>Cc:</b> Cyr, Aric <a class="moz-txt-link-rfc2396E" href="mailto:Aric.Cyr@amd.com"><Aric.Cyr@amd.com></a>; <a class="moz-txt-link-abbreviated" href="mailto:amd-gfx@lists.freedesktop.org">amd-gfx@lists.freedesktop.org</a>; Somasundaram, Meenakshikumar <a class="moz-txt-link-rfc2396E" href="mailto:Meenakshikumar.Somasundaram@amd.com"><Meenakshikumar.Somasundaram@amd.com></a>; Huang, PeiChen (Pei-Chen) <a class="moz-txt-link-rfc2396E" href="mailto:PeiChen.Huang@amd.com"><PeiChen.Huang@amd.com></a><br> <b>Subject:</b> Re: [PATCH] drm/amd/display: Fix buffer overflow in 'get_host_router_total_dp_tunnel_bw()'<o:p></o:p></p> </div> </div> <p class="MsoNormal"><o:p> </o:p></p> <p class="MsoPlainText">+ Cc: Tom Chung <<a href="mailto:chiahsuan.chung@amd.com" moz-do-not-send="true" class="moz-txt-link-freetext">chiahsuan.chung@amd.com</a>><o:p></o:p></p> <div> <p class="MsoNormal">On 1/29/2024 9:19 PM, Srinivasan Shanmugam wrote:<o:p></o:p></p> </div> <blockquote style="margin-top:5.0pt;margin-bottom:5.0pt"> <pre>The error message buffer overflow 'dc->links' 12 <= 12 suggests that the<o:p></o:p></pre> <pre>code is trying to access an element of the dc->links array that is<o:p></o:p></pre> <pre>beyond its bounds. In C, arrays are zero-indexed, so an array with 12<o:p></o:p></pre> <pre>elements has valid indices from 0 to 11. Trying to access dc->links[12]<o:p></o:p></pre> <pre>would be an attempt to access the 13th element of a 12-element array,<o:p></o:p></pre> <pre>which is a buffer overflow.<o:p></o:p></pre> <pre><o:p> </o:p></pre> <pre>To fix this, ensure that the loop does not go beyond the last valid<o:p></o:p></pre> <pre>index when accessing dc->links[i + 1] by subtracting 1 from the loop<o:p></o:p></pre> <pre>condition.<o:p></o:p></pre> <pre><o:p> </o:p></pre> <pre>This would ensure that i + 1 is always a valid index in the array.<o:p></o:p></pre> <pre><o:p> </o:p></pre> <pre>Fixes the below:<o:p></o:p></pre> <pre>drivers/gpu/drm/amd/amdgpu/../display/dc/link/protocols/link_dp_dpia_bw.c:208 get_host_router_total_dp_tunnel_bw() error: buffer overflow 'dc->links' 12 <= 12<o:p></o:p></pre> <pre><o:p> </o:p></pre> <pre>Fixes: 9ed0893b7c58 ("drm/amd/display: Add dpia display mode validation logic")<o:p></o:p></pre> <pre>Cc: PeiChen Huang <a href="mailto:peichen.huang@amd.com" moz-do-not-send="true"><peichen.huang@amd.com></a><o:p></o:p></pre> <pre>Cc: Aric Cyr <a href="mailto:aric.cyr@amd.com" moz-do-not-send="true"><aric.cyr@amd.com></a><o:p></o:p></pre> <pre>Cc: Rodrigo Siqueira <a href="mailto:rodrigo.siqueira@amd.com" moz-do-not-send="true"><rodrigo.siqueira@amd.com></a><o:p></o:p></pre> <pre>Cc: Aurabindo Pillai <a href="mailto:aurabindo.pillai@amd.com" moz-do-not-send="true"><aurabindo.pillai@amd.com></a><o:p></o:p></pre> <pre>Cc: Meenakshikumar Somasundaram <a href="mailto:meenakshikumar.somasundaram@amd.com" moz-do-not-send="true"><meenakshikumar.somasundaram@amd.com></a><o:p></o:p></pre> <pre>Signed-off-by: Srinivasan Shanmugam <a href="mailto:srinivasan.shanmugam@amd.com" moz-do-not-send="true"><srinivasan.shanmugam@amd.com></a><o:p></o:p></pre> <pre>---<o:p></o:p></pre> <pre> drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c | 2 +-<o:p></o:p></pre> <pre> 1 file changed, 1 insertion(+), 1 deletion(-)<o:p></o:p></pre> <pre><o:p> </o:p></pre> <pre>diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c<o:p></o:p></pre> <pre>index dd0d2b206462..5491b707cec8 100644<o:p></o:p></pre> <pre>--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c<o:p></o:p></pre> <pre>+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c<o:p></o:p></pre> <pre>@@ -196,7 +196,7 @@ static int get_host_router_total_dp_tunnel_bw(const struct dc *dc, uint8_t hr_in<o:p></o:p></pre> <pre> struct dc_link *link_dpia_primary, *link_dpia_secondary;<o:p></o:p></pre> <pre> int total_bw = 0;<o:p></o:p></pre> <pre> <o:p></o:p></pre> <pre>- for (uint8_t i = 0; i < MAX_PIPES * 2; ++i) {<o:p></o:p></pre> <pre>+ for (uint8_t i = 0; i < (MAX_PIPES * 2) - 1; ++i) {<o:p></o:p></pre> <pre> <o:p></o:p></pre> <pre> if (!dc->links[i] || dc->links[i]->ep_type != DISPLAY_ENDPOINT_USB4_DPIA)<o:p></o:p></pre> <pre> continue;<o:p></o:p></pre> </blockquote> </div> </div> </blockquote> </body> </html>