patch 'net/ice/base: fix iteration of TLVs in Preserved Fields Area' has been queued to stable release 22.11.7

[luca.boccassi@gmail.com]

Hi,

FYI, your patch has been queued to stable release 22.11.7

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 10/25/24. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/bluca/dpdk-stable

This queued commit can be viewed at:
https://github.com/bluca/dpdk-stable/commit/822d0a9391325d4d7ea7ce9c7e776807c3928d2e

Thanks.

Luca Boccassi

---
From 822d0a9391325d4d7ea7ce9c7e776807c3928d2e Mon Sep 17 00:00:00 2001
From: Fabio Pricoco <fabio.pricoco@intel.com>
Date: Fri, 23 Aug 2024 09:56:42 +0000
Subject: [PATCH] net/ice/base: fix iteration of TLVs in Preserved Fields Area

[ upstream commit dcb760bf0f951b404bce33a1dd14906154b58c75 ]

The ice_get_pfa_module_tlv() function iterates over the Preserved Fields
Area to read data from the Shadow RAM, including the Part Board Assembly
data, among others.

If the specific TLV being requested is not found in the current NVM, the
code will read past the end of the PFA, misinterpreting the last word of
the PFA and the word just after the PFA as another TLV. This typically
results in one extra iteration before the length check of the while loop
is triggered.

Correct the logic for determining the maximum PFA offset to include the
extra last word. Additionally, make the driver robust against overflows
by using check_add_overflow. This ensures that even if the NVM provides
bogus data, the driver will not overflow, and will instead log a useful
warning message. The check for whether the TLV length exceeds the PFA
length is also removed, in favor of relying on the overflow warning
instead.

Fixes: 5d0b7b5fc491 ("net/ice/base: add read PBA module function")

Signed-off-by: Fabio Pricoco <fabio.pricoco@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Soumyadeep Hore <soumyadeep.hore@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
---
 drivers/net/ice/base/ice_nvm.c | 36 ++++++++++++++++++++++------------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ice/base/ice_nvm.c b/drivers/net/ice/base/ice_nvm.c
index 6da52f4d58..47ead01255 100644
--- a/drivers/net/ice/base/ice_nvm.c
+++ b/drivers/net/ice/base/ice_nvm.c
@@ -471,6 +471,8 @@ enum ice_status ice_read_sr_word(struct ice_hw *hw, u16 offset, u16 *data)
 	return status;
 }
 
+#define check_add_overflow __builtin_add_overflow
+
 /**
  * ice_get_pfa_module_tlv - Reads sub module TLV from NVM PFA
  * @hw: pointer to hardware structure
@@ -487,8 +489,7 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
 		       u16 module_type)
 {
 	enum ice_status status;
-	u16 pfa_len, pfa_ptr;
-	u32 next_tlv;
+	u16 pfa_len, pfa_ptr, next_tlv, max_tlv;
 
 	status = ice_read_sr_word(hw, ICE_SR_PFA_PTR, &pfa_ptr);
 	if (status != ICE_SUCCESS) {
@@ -500,11 +501,23 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
 		ice_debug(hw, ICE_DBG_INIT, "Failed to read PFA length.\n");
 		return status;
 	}
-	/* Starting with first TLV after PFA length, iterate through the list
+
+	if (check_add_overflow(pfa_ptr, (u16)(pfa_len - 1), &max_tlv)) {
+		ice_debug(hw, ICE_DBG_INIT, "PFA starts at offset %u. PFA length of %u caused 16-bit arithmetic overflow.\n",
+				  pfa_ptr, pfa_len);
+		return ICE_ERR_INVAL_SIZE;
+	}
+
+	/* The Preserved Fields Area contains a sequence of TLVs which define
+	 * its contents. The PFA length includes all of the TLVs, plus its
+	 * initial length word itself, *and* one final word at the end of all
+	 * of the TLVs.
+	 *
+	 * Starting with first TLV after PFA length, iterate through the list
 	 * of TLVs to find the requested one.
 	 */
 	next_tlv = pfa_ptr + 1;
-	while (next_tlv < ((u32)pfa_ptr + pfa_len)) {
+	while (next_tlv < max_tlv) {
 		u16 tlv_sub_module_type;
 		u16 tlv_len;
 
@@ -521,10 +534,6 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
 			ice_debug(hw, ICE_DBG_INIT, "Failed to read TLV length.\n");
 			break;
 		}
-		if (tlv_len > pfa_len) {
-			ice_debug(hw, ICE_DBG_INIT, "Invalid TLV length.\n");
-			return ICE_ERR_INVAL_SIZE;
-		}
 		if (tlv_sub_module_type == module_type) {
 			if (tlv_len) {
 				*module_tlv = (u16)next_tlv;
@@ -533,10 +542,13 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
 			}
 			return ICE_ERR_INVAL_SIZE;
 		}
-		/* Check next TLV, i.e. current TLV pointer + length + 2 words
-		 * (for current TLV's type and length)
-		 */
-		next_tlv = next_tlv + tlv_len + 2;
+
+		if (check_add_overflow(next_tlv, (u16)2, &next_tlv) ||
+		    check_add_overflow(next_tlv, tlv_len, &next_tlv)) {
+			ice_debug(hw, ICE_DBG_INIT, "TLV of type %u and length 0x%04x caused 16-bit arithmetic overflow. The PFA starts at 0x%04x and has length of 0x%04x\n",
+					  tlv_sub_module_type, tlv_len, pfa_ptr, pfa_len);
+			return ICE_ERR_INVAL_SIZE;
+		}
 	}
 	/* Module does not exist */
 	return ICE_ERR_DOES_NOT_EXIST;
-- 
2.45.2

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2024-10-23 22:16:41.891229585 +0100
+++ 0036-net-ice-base-fix-iteration-of-TLVs-in-Preserved-Fiel.patch	2024-10-23 22:16:40.475941807 +0100
@@ -1 +1 @@
-From dcb760bf0f951b404bce33a1dd14906154b58c75 Mon Sep 17 00:00:00 2001
+From 822d0a9391325d4d7ea7ce9c7e776807c3928d2e Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit dcb760bf0f951b404bce33a1dd14906154b58c75 ]
+
@@ -25 +26,0 @@
-Cc: stable@dpdk.org
@@ -36 +37 @@
-index 5e982de4b5..56c6c96a95 100644
+index 6da52f4d58..47ead01255 100644
@@ -39 +40 @@
-@@ -469,6 +469,8 @@ int ice_read_sr_word(struct ice_hw *hw, u16 offset, u16 *data)
+@@ -471,6 +471,8 @@ enum ice_status ice_read_sr_word(struct ice_hw *hw, u16 offset, u16 *data)
@@ -48,2 +49 @@
-@@ -484,8 +486,7 @@ int
- ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
+@@ -487,8 +489,7 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
@@ -51,0 +52 @@
+ 	enum ice_status status;
@@ -55 +55,0 @@
- 	int status;
@@ -58 +58,2 @@
-@@ -498,11 +499,23 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
+ 	if (status != ICE_SUCCESS) {
+@@ -500,11 +501,23 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
@@ -84 +85 @@
-@@ -519,10 +532,6 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
+@@ -521,10 +534,6 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
@@ -95 +96 @@
-@@ -531,10 +540,13 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
+@@ -533,10 +542,13 @@ ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,