commit ea2c6a2038c8b257cab54b69a15a41529e1908b3
author Ali Labbene <ali.labbene@st.com> Fri Nov 25 14:17:39 2022 +0100
committer Ali Labbene <ali.labbene@st.com> Fri Nov 25 14:17:39 2022 +0100
tree d5a12f83213bd8dd3e31ff93abafda8877b99459
parent 89f4708d851c84c12fd23cffd3e518c962135142

[HAL][DAC] Fix HAL_GetTick() timeout vulnerability

Src/stm32l4xx_hal_dac.c

diff --git a/Src/stm32l4xx_hal_dac.c b/Src/stm32l4xx_hal_dac.c
index 814ef66..cdbd949 100644
--- a/Src/stm32l4xx_hal_dac.c
+++ b/Src/stm32l4xx_hal_dac.c
@@ -1249,13 +1249,17 @@
         /* Check for the Timeout */
         if ((HAL_GetTick() - tickstart) > TIMEOUT_DAC_CALIBCONFIG)
         {
-          /* Update error code */
-          SET_BIT(hdac->ErrorCode, HAL_DAC_ERROR_TIMEOUT);
+          /* New check to avoid false timeout detection in case of preemption */
+          if(((hdac->Instance->SR) & DAC_SR_BWST1) != 0UL)
+          {
+            /* Update error code */
+            SET_BIT(hdac->ErrorCode, HAL_DAC_ERROR_TIMEOUT);
 
-          /* Change the DMA state */
-          hdac->State = HAL_DAC_STATE_TIMEOUT;
+            /* Change the DMA state */
+            hdac->State = HAL_DAC_STATE_TIMEOUT;
 
-          return HAL_TIMEOUT;
+            return HAL_TIMEOUT;
+          }
         }
       }
       HAL_Delay(1);
@@ -1271,13 +1275,17 @@
         /* Check for the Timeout */
         if ((HAL_GetTick() - tickstart) > TIMEOUT_DAC_CALIBCONFIG)
         {
-          /* Update error code */
-          SET_BIT(hdac->ErrorCode, HAL_DAC_ERROR_TIMEOUT);
+          /* New check to avoid false timeout detection in case of preemption */
+          if(((hdac->Instance->SR) & DAC_SR_BWST2) != 0UL)
+          {
+            /* Update error code */
+            SET_BIT(hdac->ErrorCode, HAL_DAC_ERROR_TIMEOUT);
 
-          /* Change the DMA state */
-          hdac->State = HAL_DAC_STATE_TIMEOUT;
+            /* Change the DMA state */
+            hdac->State = HAL_DAC_STATE_TIMEOUT;
 
-          return HAL_TIMEOUT;
+            return HAL_TIMEOUT;
+          }
         }
       }
       HAL_Delay(1U);