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From:   Ira Weiny <ira.weiny@intel.com>
Date:   Fri, 17 Nov 2023 17:14:21 -0800
Subject: [PATCH 1/2] cxl/cdat: Handle cdat table build errors
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Message-Id: <20231117-fix-cdat-cs-v1-1-ffc2b116ca6c@intel.com>
References: <20231117-fix-cdat-cs-v1-0-ffc2b116ca6c@intel.com>
In-Reply-To: <20231117-fix-cdat-cs-v1-0-ffc2b116ca6c@intel.com>
To:     Jonathan Cameron <jonathan.cameron@huawei.com>,
        Fan Ni <nifan.cxl@gmail.com>
Cc:     linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org,
        Ira Weiny <ira.weiny@intel.com>
Precedence: bulk

The callback for building CDAT tables may return negative error codes.
This was previously unhandled and will result in potentially huge
allocations later on in ct3_build_cdat()

Detect the negative error code and defer cdat building.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>

---
This likely needs to have some more robust error handling in the event
of errors.  But this at least prevents more errors down the line with
invalid allocations.
---
 hw/cxl/cxl-cdat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/cxl/cxl-cdat.c b/hw/cxl/cxl-cdat.c
index 639a2db3e17b..24829cf2428d 100644
--- a/hw/cxl/cxl-cdat.c
+++ b/hw/cxl/cxl-cdat.c
@@ -63,7 +63,7 @@ static void ct3_build_cdat(CDATObject *cdat, Error **errp)
     cdat->built_buf_len = cdat->build_cdat_table(&cdat->built_buf,
                                                  cdat->private);
 
-    if (!cdat->built_buf_len) {
+    if (cdat->built_buf_len <= 0) {
         /* Build later as not all data available yet */
         cdat->to_update = true;
         return;

-- 
2.41.0