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* [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs
@ 2026-08-01 11:25 Zhiling Zou
  2026-08-01 15:00 ` Ilya Maximets
                   ` (3 more replies)
  0 siblings, 4 replies; 5+ messages in thread
From: Zhiling Zou @ 2026-08-01 11:25 UTC (permalink / raw)
  To: netdev, dev, i.maximets
  Cc: aconole, echaudro, davem, edumazet, kuba, pabeni, horms, vega,
	zhilinz

ovs_flow_cmd_new() preallocates the optional reply skb before it takes
ovs_mutex and before it knows which existing flow will be updated.

That is normally fine because the skb is sized from the request flow
identifier.  That identifier also becomes the inserted flow's identifier.
For updates, however, a request with a UFID may miss the UFID lookup and
then fall back to the flow key lookup.  That lookup can legitimately find
an existing key-identified flow.  UFIDs are optional and the flow key is
the primary identifier.

For echoed replies, ovs_flow_cmd_fill_info() writes the matched flow's
identifier, not the request identifier used for the preallocation.  A short
request UFID can therefore leave too little room for the key identifier.
The fill can then fail with -EMSGSIZE and hit the BUG_ON(error < 0) in the
update path.

Once the update target has been resolved, reallocate the reply skb if the
matched flow needs a larger reply than the request identifier allowed.  Do
this before replacing the actions so the request can still fail cleanly if
the rare extra allocation fails.

Fixes: 74ed7ab9264c ("openvswitch: Add support for unique flow IDs.")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
---
changes in v4:
- Split the reply size comparison into current and desired variables as
  requested by Ilya Maximets.
- v3 Link: https://lore.kernel.org/all/c773b2726dda8d90eed6d42b2f9741810a7a46e1.1785288876.git.zhilinz@nebusec.ai/

changes in v3:
- Compare computed reply sizes instead of UFID contents.
- Inline the rare reallocation check and add spacing around the update checks.
- v2 Link: https://lore.kernel.org/all/71380bcfbf3aed9a6a8a9daeef6592fa5a4fb245.1785211788.git.zhilinz@nebusec.ai/

changes in v2:
- Preserve valid key/UFID mixed flow updates as requested by Ilya Maximets.
- Reallocate the echoed reply skb with the matched flow identifier before replacing actions.
- v1 Link: https://lore.kernel.org/all/fa4f85fe7becb164a8a1849aa77ceeb1c08b078c.1784881178.git.zhilinz@nebusec.ai/

 net/openvswitch/datapath.c | 28 +++++++++++++++++++++++++---
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index eaf332b156d73..d73d729176e1f 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -1113,9 +1113,8 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
 			error = -EEXIST;
 			goto err_unlock_ovs;
 		}
-		/* The flow identifier has to be the same for flow updates.
-		 * Look for any overlapping flow.
-		 */
+
+		/* Look for any overlapping flow. */
 		if (unlikely(!ovs_flow_cmp(flow, &match))) {
 			if (ovs_identifier_is_key(&flow->id))
 				flow = ovs_flow_tbl_lookup_exact(&dp->table,
@@ -1127,6 +1126,29 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
 				goto err_unlock_ovs;
 			}
 		}
+
+		if (unlikely(reply)) {
+			size_t current, desired;
+
+			current = ovs_flow_cmd_msg_size(acts, &new_flow->id,
+							ufid_flags);
+			desired = ovs_flow_cmd_msg_size(acts, &flow->id,
+							ufid_flags);
+			if (current < desired) {
+				struct sk_buff *resized;
+
+				resized = ovs_flow_cmd_alloc_info(acts, &flow->id,
+								  info, false,
+								  ufid_flags);
+				if (IS_ERR(resized)) {
+					error = PTR_ERR(resized);
+					goto err_unlock_ovs;
+				}
+				kfree_skb(reply);
+				reply = resized;
+			}
+		}
+
 		/* Update actions. */
 		old_acts = ovsl_dereference(flow->sf_acts);
 		rcu_assign_pointer(flow->sf_acts, acts);
-- 
2.43.0

^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs
  2026-08-01 11:25 [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs Zhiling Zou
@ 2026-08-01 15:00 ` Ilya Maximets
  2026-08-08 14:23 ` kernel test robot
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 5+ messages in thread
From: Ilya Maximets @ 2026-08-01 15:00 UTC (permalink / raw)
  To: Zhiling Zou, netdev, dev, i.maximets
  Cc: aconole, echaudro, davem, edumazet, kuba, pabeni, horms, vega

On 8/1/26 1:25 PM, Zhiling Zou wrote:
> ovs_flow_cmd_new() preallocates the optional reply skb before it takes
> ovs_mutex and before it knows which existing flow will be updated.
> 
> That is normally fine because the skb is sized from the request flow
> identifier.  That identifier also becomes the inserted flow's identifier.
> For updates, however, a request with a UFID may miss the UFID lookup and
> then fall back to the flow key lookup.  That lookup can legitimately find
> an existing key-identified flow.  UFIDs are optional and the flow key is
> the primary identifier.
> 
> For echoed replies, ovs_flow_cmd_fill_info() writes the matched flow's
> identifier, not the request identifier used for the preallocation.  A short
> request UFID can therefore leave too little room for the key identifier.
> The fill can then fail with -EMSGSIZE and hit the BUG_ON(error < 0) in the
> update path.
> 
> Once the update target has been resolved, reallocate the reply skb if the
> matched flow needs a larger reply than the request identifier allowed.  Do
> this before replacing the actions so the request can still fail cleanly if
> the rare extra allocation fails.
> 
> Fixes: 74ed7ab9264c ("openvswitch: Add support for unique flow IDs.")
> Cc: stable@vger.kernel.org
> Reported-by: Vega <vega@nebusec.ai>
> Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
> ---
> changes in v4:
> - Split the reply size comparison into current and desired variables as
>   requested by Ilya Maximets.
> - v3 Link: https://lore.kernel.org/all/c773b2726dda8d90eed6d42b2f9741810a7a46e1.1785288876.git.zhilinz@nebusec.ai/
> 
> changes in v3:
> - Compare computed reply sizes instead of UFID contents.
> - Inline the rare reallocation check and add spacing around the update checks.
> - v2 Link: https://lore.kernel.org/all/71380bcfbf3aed9a6a8a9daeef6592fa5a4fb245.1785211788.git.zhilinz@nebusec.ai/
> 
> changes in v2:
> - Preserve valid key/UFID mixed flow updates as requested by Ilya Maximets.
> - Reallocate the echoed reply skb with the matched flow identifier before replacing actions.
> - v1 Link: https://lore.kernel.org/all/fa4f85fe7becb164a8a1849aa77ceeb1c08b078c.1784881178.git.zhilinz@nebusec.ai/
> 
>  net/openvswitch/datapath.c | 28 +++++++++++++++++++++++++---
>  1 file changed, 25 insertions(+), 3 deletions(-)
> 
> diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
> index eaf332b156d73..d73d729176e1f 100644
> --- a/net/openvswitch/datapath.c
> +++ b/net/openvswitch/datapath.c
> @@ -1113,9 +1113,8 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
>  			error = -EEXIST;
>  			goto err_unlock_ovs;
>  		}
> -		/* The flow identifier has to be the same for flow updates.
> -		 * Look for any overlapping flow.
> -		 */
> +
> +		/* Look for any overlapping flow. */
>  		if (unlikely(!ovs_flow_cmp(flow, &match))) {
>  			if (ovs_identifier_is_key(&flow->id))
>  				flow = ovs_flow_tbl_lookup_exact(&dp->table,
> @@ -1127,6 +1126,29 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
>  				goto err_unlock_ovs;
>  			}
>  		}
> +
> +		if (unlikely(reply)) {
> +			size_t current, desired;

Unfortunately, this breaks the build.  Please, make sure the code
compiles without warnings before posting patches, don't just copy
suggestions.

Let's rename these into 'cur' and 'req' (required).

> +
> +			current = ovs_flow_cmd_msg_size(acts, &new_flow->id,
> +							ufid_flags);
> +			desired = ovs_flow_cmd_msg_size(acts, &flow->id,
> +							ufid_flags);
> +			if (current < desired) {
> +				struct sk_buff *resized;
> +
> +				resized = ovs_flow_cmd_alloc_info(acts, &flow->id,

This line is too long.  The line length check for netdev patches
is 80.  Move the id to the next line.

> +								  info, false,
> +								  ufid_flags);
> +				if (IS_ERR(resized)) {
> +					error = PTR_ERR(resized);
> +					goto err_unlock_ovs;
> +				}
> +				kfree_skb(reply);
> +				reply = resized;
> +			}
> +		}
> +
>  		/* Update actions. */
>  		old_acts = ovsl_dereference(flow->sf_acts);
>  		rcu_assign_pointer(flow->sf_acts, acts);


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs
  2026-08-01 11:25 [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs Zhiling Zou
  2026-08-01 15:00 ` Ilya Maximets
@ 2026-08-08 14:23 ` kernel test robot
  2026-08-08 17:33 ` kernel test robot
  2026-08-08 22:19 ` kernel test robot
  3 siblings, 0 replies; 5+ messages in thread
From: kernel test robot @ 2026-08-08 14:23 UTC (permalink / raw)
  To: Zhiling Zou, netdev, dev, i.maximets
  Cc: oe-kbuild-all, aconole, echaudro, davem, edumazet, kuba, pabeni,
	horms, vega, zhilinz

Hi Zhiling,

kernel test robot noticed the following build errors:

[auto build test ERROR on horms-ipvs/master]
[also build test ERROR on v7.2-rc6]
[cannot apply to net/main net-next/main linus/master next-20260807]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Zhiling-Zou/net-openvswitch-reallocate-update-replies-for-mismatched-IDs/20260808-205431
base:   https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs.git master
patch link:    https://lore.kernel.org/r/3b76cbe50252a5650c3b69c789ed36481d0bbee4.1785583308.git.zhilinz%40nebusec.ai
patch subject: [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs
config: alpha-allmodconfig (https://download.01.org/0day-ci/archive/20260808/202608082248.euvm5RXc-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 16.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260808/202608082248.euvm5RXc-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202608082248.euvm5RXc-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from ./arch/alpha/include/generated/asm/current.h:1,
                    from arch/alpha/include/asm/spinlock.h:6,
                    from include/linux/spinlock.h:94,
                    from include/linux/kref.h:16,
                    from include/linux/mm_types.h:8,
                    from include/linux/buildid.h:5,
                    from include/linux/module.h:14,
                    from net/openvswitch/datapath.c:9:
   net/openvswitch/datapath.c: In function 'ovs_flow_cmd_new':
>> include/asm-generic/current.h:7:45: error: expected ')' before '->' token
       7 | #define get_current() (current_thread_info()->task)
         |                                             ^~
   include/asm-generic/current.h:8:17: note: in expansion of macro 'get_current'
       8 | #define current get_current()
         |                 ^~~~~~~~~~~
   net/openvswitch/datapath.c:1100:32: note: in expansion of macro 'current'
    1100 |                         size_t current, desired;
         |                                ^~~~~~~
>> net/openvswitch/datapath.c:1102:33: error: assignment to 'struct task_struct *' from 'size_t' {aka 'long unsigned int'} makes pointer from integer without a cast [-Wint-conversion]
    1102 |                         current = ovs_flow_cmd_msg_size(acts, &new_flow->id,
         |                                 ^
>> net/openvswitch/datapath.c:1104:25: error: 'desired' undeclared (first use in this function)
    1104 |                         desired = ovs_flow_cmd_msg_size(acts, &flow->id,
         |                         ^~~~~~~
   net/openvswitch/datapath.c:1104:25: note: each undeclared identifier is reported only once for each function it appears in


vim +1102 net/openvswitch/datapath.c

   966	
   967	static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
   968	{
   969		struct net *net = sock_net(skb->sk);
   970		struct nlattr **a = info->attrs;
   971		struct ovs_header *ovs_header = info->userhdr;
   972		struct sw_flow *flow = NULL, *new_flow;
   973		struct sw_flow_mask mask;
   974		struct sk_buff *reply;
   975		struct datapath *dp;
   976		struct sw_flow_key *key;
   977		struct sw_flow_actions *acts;
   978		struct sw_flow_match match;
   979		u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
   980		int error;
   981		bool log = !a[OVS_FLOW_ATTR_PROBE];
   982	
   983		/* Must have key and actions. */
   984		error = -EINVAL;
   985		if (!a[OVS_FLOW_ATTR_KEY]) {
   986			OVS_NLERR(log, "Flow key attr not present in new flow.");
   987			goto error;
   988		}
   989		if (!a[OVS_FLOW_ATTR_ACTIONS]) {
   990			OVS_NLERR(log, "Flow actions attr not present in new flow.");
   991			goto error;
   992		}
   993	
   994		/* Most of the time we need to allocate a new flow, do it before
   995		 * locking.
   996		 */
   997		new_flow = ovs_flow_alloc();
   998		if (IS_ERR(new_flow)) {
   999			error = PTR_ERR(new_flow);
  1000			goto error;
  1001		}
  1002	
  1003		/* Extract key. */
  1004		key = kzalloc(sizeof(*key), GFP_KERNEL);
  1005		if (!key) {
  1006			error = -ENOMEM;
  1007			goto err_kfree_flow;
  1008		}
  1009	
  1010		ovs_match_init(&match, key, false, &mask);
  1011		error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
  1012					  a[OVS_FLOW_ATTR_MASK], log);
  1013		if (error)
  1014			goto err_kfree_key;
  1015	
  1016		ovs_flow_mask_key(&new_flow->key, key, true, &mask);
  1017	
  1018		/* Extract flow identifier. */
  1019		error = ovs_nla_get_identifier(&new_flow->id, a[OVS_FLOW_ATTR_UFID],
  1020					       key, log);
  1021		if (error)
  1022			goto err_kfree_key;
  1023	
  1024		/* Validate actions. */
  1025		error = ovs_nla_copy_actions(net, a[OVS_FLOW_ATTR_ACTIONS],
  1026					     &new_flow->key, &acts, log);
  1027		if (error) {
  1028			OVS_NLERR(log, "Flow actions may not be safe on all matching packets.");
  1029			goto err_kfree_key;
  1030		}
  1031	
  1032		reply = ovs_flow_cmd_alloc_info(acts, &new_flow->id, info, false,
  1033						ufid_flags);
  1034		if (IS_ERR(reply)) {
  1035			error = PTR_ERR(reply);
  1036			goto err_kfree_acts;
  1037		}
  1038	
  1039		ovs_lock();
  1040		dp = get_dp(net, ovs_header->dp_ifindex);
  1041		if (unlikely(!dp)) {
  1042			error = -ENODEV;
  1043			goto err_unlock_ovs;
  1044		}
  1045	
  1046		/* Check if this is a duplicate flow */
  1047		if (ovs_identifier_is_ufid(&new_flow->id))
  1048			flow = ovs_flow_tbl_lookup_ufid(&dp->table, &new_flow->id);
  1049		if (!flow)
  1050			flow = ovs_flow_tbl_lookup(&dp->table, key);
  1051		if (likely(!flow)) {
  1052			rcu_assign_pointer(new_flow->sf_acts, acts);
  1053	
  1054			/* Put flow in bucket. */
  1055			error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
  1056			if (unlikely(error)) {
  1057				acts = NULL;
  1058				goto err_unlock_ovs;
  1059			}
  1060	
  1061			if (unlikely(reply)) {
  1062				error = ovs_flow_cmd_fill_info(new_flow,
  1063							       ovs_header->dp_ifindex,
  1064							       reply, info->snd_portid,
  1065							       info->snd_seq, 0,
  1066							       OVS_FLOW_CMD_NEW,
  1067							       ufid_flags);
  1068				BUG_ON(error < 0);
  1069			}
  1070			ovs_unlock();
  1071		} else {
  1072			struct sw_flow_actions *old_acts;
  1073	
  1074			/* Bail out if we're not allowed to modify an existing flow.
  1075			 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
  1076			 * because Generic Netlink treats the latter as a dump
  1077			 * request.  We also accept NLM_F_EXCL in case that bug ever
  1078			 * gets fixed.
  1079			 */
  1080			if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
  1081								 | NLM_F_EXCL))) {
  1082				error = -EEXIST;
  1083				goto err_unlock_ovs;
  1084			}
  1085	
  1086			/* Look for any overlapping flow. */
  1087			if (unlikely(!ovs_flow_cmp(flow, &match))) {
  1088				if (ovs_identifier_is_key(&flow->id))
  1089					flow = ovs_flow_tbl_lookup_exact(&dp->table,
  1090									 &match);
  1091				else /* UFID matches but key is different */
  1092					flow = NULL;
  1093				if (!flow) {
  1094					error = -ENOENT;
  1095					goto err_unlock_ovs;
  1096				}
  1097			}
  1098	
  1099			if (unlikely(reply)) {
> 1100				size_t current, desired;
  1101	
> 1102				current = ovs_flow_cmd_msg_size(acts, &new_flow->id,
  1103								ufid_flags);
> 1104				desired = ovs_flow_cmd_msg_size(acts, &flow->id,
  1105								ufid_flags);
  1106				if (current < desired) {
  1107					struct sk_buff *resized;
  1108	
  1109					resized = ovs_flow_cmd_alloc_info(acts, &flow->id,
  1110									  info, false,
  1111									  ufid_flags);
  1112					if (IS_ERR(resized)) {
  1113						error = PTR_ERR(resized);
  1114						goto err_unlock_ovs;
  1115					}
  1116					kfree_skb(reply);
  1117					reply = resized;
  1118				}
  1119			}
  1120	
  1121			/* Update actions. */
  1122			old_acts = ovsl_dereference(flow->sf_acts);
  1123			rcu_assign_pointer(flow->sf_acts, acts);
  1124	
  1125			if (unlikely(reply)) {
  1126				error = ovs_flow_cmd_fill_info(flow,
  1127							       ovs_header->dp_ifindex,
  1128							       reply, info->snd_portid,
  1129							       info->snd_seq, 0,
  1130							       OVS_FLOW_CMD_NEW,
  1131							       ufid_flags);
  1132				BUG_ON(error < 0);
  1133			}
  1134			ovs_unlock();
  1135	
  1136			ovs_nla_free_flow_actions_rcu(old_acts);
  1137			ovs_flow_free(new_flow, false);
  1138		}
  1139	
  1140		if (reply)
  1141			ovs_notify(&dp_flow_genl_family, reply, info);
  1142	
  1143		kfree(key);
  1144		return 0;
  1145	
  1146	err_unlock_ovs:
  1147		ovs_unlock();
  1148		kfree_skb(reply);
  1149	err_kfree_acts:
  1150		ovs_nla_free_flow_actions(acts);
  1151	err_kfree_key:
  1152		kfree(key);
  1153	err_kfree_flow:
  1154		ovs_flow_free(new_flow, false);
  1155	error:
  1156		return error;
  1157	}
  1158	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs
  2026-08-01 11:25 [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs Zhiling Zou
  2026-08-01 15:00 ` Ilya Maximets
  2026-08-08 14:23 ` kernel test robot
@ 2026-08-08 17:33 ` kernel test robot
  2026-08-08 22:19 ` kernel test robot
  3 siblings, 0 replies; 5+ messages in thread
From: kernel test robot @ 2026-08-08 17:33 UTC (permalink / raw)
  To: Zhiling Zou, netdev, dev, i.maximets
  Cc: oe-kbuild-all, aconole, echaudro, davem, edumazet, kuba, pabeni,
	horms, vega, zhilinz

Hi Zhiling,

kernel test robot noticed the following build errors:

[auto build test ERROR on horms-ipvs/master]
[also build test ERROR on v7.2-rc6]
[cannot apply to net/main net-next/main linus/master next-20260807]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Zhiling-Zou/net-openvswitch-reallocate-update-replies-for-mismatched-IDs/20260808-205431
base:   https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs.git master
patch link:    https://lore.kernel.org/r/3b76cbe50252a5650c3b69c789ed36481d0bbee4.1785583308.git.zhilinz%40nebusec.ai
patch subject: [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs
config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20260809/202608090140.jJdhfFjc-lkp@intel.com/config)
compiler: powerpc64-linux-gcc (GCC) 16.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260809/202608090140.jJdhfFjc-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202608090140.jJdhfFjc-lkp@intel.com/

All errors (new ones prefixed by >>):

   net/openvswitch/datapath.c: In function 'ovs_flow_cmd_new':
>> net/openvswitch/datapath.c:1100:25: error: function declaration isn't a prototype [-Werror=strict-prototypes]
    1100 |                         size_t current, desired;
         |                         ^~~~~~
   In file included from include/linux/thread_info.h:23,
                    from include/asm-generic/preempt.h:5,
                    from ./arch/powerpc/include/generated/asm/preempt.h:1,
                    from include/linux/preempt.h:78,
                    from include/linux/spinlock.h:56,
                    from include/linux/kref.h:16,
                    from include/linux/mm_types.h:8,
                    from include/linux/buildid.h:5,
                    from include/linux/module.h:14,
                    from net/openvswitch/datapath.c:9:
>> arch/powerpc/include/asm/current.h:26:17: error: conflicting types for 'get_current'; have 'size_t()' {aka 'long unsigned int()'}
      26 | #define current get_current()
         |                 ^~~~~~~~~~~
   net/openvswitch/datapath.c:1100:32: note: in expansion of macro 'current'
    1100 |                         size_t current, desired;
         |                                ^~~~~~~
   arch/powerpc/include/asm/current.h:15:35: note: previous definition of 'get_current' with type 'struct task_struct *(void)'
      15 | static inline struct task_struct *get_current(void)
         |                                   ^~~~~~~~~~~
>> net/openvswitch/datapath.c:1102:33: error: lvalue required as left operand of assignment
    1102 |                         current = ovs_flow_cmd_msg_size(acts, &new_flow->id,
         |                                 ^
   cc1: some warnings being treated as errors


vim +1100 net/openvswitch/datapath.c

   966	
   967	static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
   968	{
   969		struct net *net = sock_net(skb->sk);
   970		struct nlattr **a = info->attrs;
   971		struct ovs_header *ovs_header = info->userhdr;
   972		struct sw_flow *flow = NULL, *new_flow;
   973		struct sw_flow_mask mask;
   974		struct sk_buff *reply;
   975		struct datapath *dp;
   976		struct sw_flow_key *key;
   977		struct sw_flow_actions *acts;
   978		struct sw_flow_match match;
   979		u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
   980		int error;
   981		bool log = !a[OVS_FLOW_ATTR_PROBE];
   982	
   983		/* Must have key and actions. */
   984		error = -EINVAL;
   985		if (!a[OVS_FLOW_ATTR_KEY]) {
   986			OVS_NLERR(log, "Flow key attr not present in new flow.");
   987			goto error;
   988		}
   989		if (!a[OVS_FLOW_ATTR_ACTIONS]) {
   990			OVS_NLERR(log, "Flow actions attr not present in new flow.");
   991			goto error;
   992		}
   993	
   994		/* Most of the time we need to allocate a new flow, do it before
   995		 * locking.
   996		 */
   997		new_flow = ovs_flow_alloc();
   998		if (IS_ERR(new_flow)) {
   999			error = PTR_ERR(new_flow);
  1000			goto error;
  1001		}
  1002	
  1003		/* Extract key. */
  1004		key = kzalloc(sizeof(*key), GFP_KERNEL);
  1005		if (!key) {
  1006			error = -ENOMEM;
  1007			goto err_kfree_flow;
  1008		}
  1009	
  1010		ovs_match_init(&match, key, false, &mask);
  1011		error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
  1012					  a[OVS_FLOW_ATTR_MASK], log);
  1013		if (error)
  1014			goto err_kfree_key;
  1015	
  1016		ovs_flow_mask_key(&new_flow->key, key, true, &mask);
  1017	
  1018		/* Extract flow identifier. */
  1019		error = ovs_nla_get_identifier(&new_flow->id, a[OVS_FLOW_ATTR_UFID],
  1020					       key, log);
  1021		if (error)
  1022			goto err_kfree_key;
  1023	
  1024		/* Validate actions. */
  1025		error = ovs_nla_copy_actions(net, a[OVS_FLOW_ATTR_ACTIONS],
  1026					     &new_flow->key, &acts, log);
  1027		if (error) {
  1028			OVS_NLERR(log, "Flow actions may not be safe on all matching packets.");
  1029			goto err_kfree_key;
  1030		}
  1031	
  1032		reply = ovs_flow_cmd_alloc_info(acts, &new_flow->id, info, false,
  1033						ufid_flags);
  1034		if (IS_ERR(reply)) {
  1035			error = PTR_ERR(reply);
  1036			goto err_kfree_acts;
  1037		}
  1038	
  1039		ovs_lock();
  1040		dp = get_dp(net, ovs_header->dp_ifindex);
  1041		if (unlikely(!dp)) {
  1042			error = -ENODEV;
  1043			goto err_unlock_ovs;
  1044		}
  1045	
  1046		/* Check if this is a duplicate flow */
  1047		if (ovs_identifier_is_ufid(&new_flow->id))
  1048			flow = ovs_flow_tbl_lookup_ufid(&dp->table, &new_flow->id);
  1049		if (!flow)
  1050			flow = ovs_flow_tbl_lookup(&dp->table, key);
  1051		if (likely(!flow)) {
  1052			rcu_assign_pointer(new_flow->sf_acts, acts);
  1053	
  1054			/* Put flow in bucket. */
  1055			error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
  1056			if (unlikely(error)) {
  1057				acts = NULL;
  1058				goto err_unlock_ovs;
  1059			}
  1060	
  1061			if (unlikely(reply)) {
  1062				error = ovs_flow_cmd_fill_info(new_flow,
  1063							       ovs_header->dp_ifindex,
  1064							       reply, info->snd_portid,
  1065							       info->snd_seq, 0,
  1066							       OVS_FLOW_CMD_NEW,
  1067							       ufid_flags);
  1068				BUG_ON(error < 0);
  1069			}
  1070			ovs_unlock();
  1071		} else {
  1072			struct sw_flow_actions *old_acts;
  1073	
  1074			/* Bail out if we're not allowed to modify an existing flow.
  1075			 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
  1076			 * because Generic Netlink treats the latter as a dump
  1077			 * request.  We also accept NLM_F_EXCL in case that bug ever
  1078			 * gets fixed.
  1079			 */
  1080			if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
  1081								 | NLM_F_EXCL))) {
  1082				error = -EEXIST;
  1083				goto err_unlock_ovs;
  1084			}
  1085	
  1086			/* Look for any overlapping flow. */
  1087			if (unlikely(!ovs_flow_cmp(flow, &match))) {
  1088				if (ovs_identifier_is_key(&flow->id))
  1089					flow = ovs_flow_tbl_lookup_exact(&dp->table,
  1090									 &match);
  1091				else /* UFID matches but key is different */
  1092					flow = NULL;
  1093				if (!flow) {
  1094					error = -ENOENT;
  1095					goto err_unlock_ovs;
  1096				}
  1097			}
  1098	
  1099			if (unlikely(reply)) {
> 1100				size_t current, desired;
  1101	
> 1102				current = ovs_flow_cmd_msg_size(acts, &new_flow->id,
  1103								ufid_flags);
  1104				desired = ovs_flow_cmd_msg_size(acts, &flow->id,
  1105								ufid_flags);
  1106				if (current < desired) {
  1107					struct sk_buff *resized;
  1108	
  1109					resized = ovs_flow_cmd_alloc_info(acts, &flow->id,
  1110									  info, false,
  1111									  ufid_flags);
  1112					if (IS_ERR(resized)) {
  1113						error = PTR_ERR(resized);
  1114						goto err_unlock_ovs;
  1115					}
  1116					kfree_skb(reply);
  1117					reply = resized;
  1118				}
  1119			}
  1120	
  1121			/* Update actions. */
  1122			old_acts = ovsl_dereference(flow->sf_acts);
  1123			rcu_assign_pointer(flow->sf_acts, acts);
  1124	
  1125			if (unlikely(reply)) {
  1126				error = ovs_flow_cmd_fill_info(flow,
  1127							       ovs_header->dp_ifindex,
  1128							       reply, info->snd_portid,
  1129							       info->snd_seq, 0,
  1130							       OVS_FLOW_CMD_NEW,
  1131							       ufid_flags);
  1132				BUG_ON(error < 0);
  1133			}
  1134			ovs_unlock();
  1135	
  1136			ovs_nla_free_flow_actions_rcu(old_acts);
  1137			ovs_flow_free(new_flow, false);
  1138		}
  1139	
  1140		if (reply)
  1141			ovs_notify(&dp_flow_genl_family, reply, info);
  1142	
  1143		kfree(key);
  1144		return 0;
  1145	
  1146	err_unlock_ovs:
  1147		ovs_unlock();
  1148		kfree_skb(reply);
  1149	err_kfree_acts:
  1150		ovs_nla_free_flow_actions(acts);
  1151	err_kfree_key:
  1152		kfree(key);
  1153	err_kfree_flow:
  1154		ovs_flow_free(new_flow, false);
  1155	error:
  1156		return error;
  1157	}
  1158	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs
  2026-08-01 11:25 [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs Zhiling Zou
                   ` (2 preceding siblings ...)
  2026-08-08 17:33 ` kernel test robot
@ 2026-08-08 22:19 ` kernel test robot
  3 siblings, 0 replies; 5+ messages in thread
From: kernel test robot @ 2026-08-08 22:19 UTC (permalink / raw)
  To: Zhiling Zou, netdev, dev, i.maximets
  Cc: oe-kbuild-all, aconole, echaudro, davem, edumazet, kuba, pabeni,
	horms, vega, zhilinz

Hi Zhiling,

kernel test robot noticed the following build warnings:

[auto build test WARNING on horms-ipvs/master]
[also build test WARNING on v7.2-rc6]
[cannot apply to net/main net-next/main linus/master next-20260807]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Zhiling-Zou/net-openvswitch-reallocate-update-replies-for-mismatched-IDs/20260808-205431
base:   https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs.git master
patch link:    https://lore.kernel.org/r/3b76cbe50252a5650c3b69c789ed36481d0bbee4.1785583308.git.zhilinz%40nebusec.ai
patch subject: [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs
config: nios2-allmodconfig (https://download.01.org/0day-ci/archive/20260809/202608090656.Aevl8bsK-lkp@intel.com/config)
compiler: nios2-linux-gcc (GCC) 11.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260809/202608090656.Aevl8bsK-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202608090656.Aevl8bsK-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from ./arch/nios2/include/generated/asm/current.h:1,
                    from include/linux/wait.h:11,
                    from include/linux/swait.h:8,
                    from include/linux/completion.h:12,
                    from include/linux/mm_types.h:14,
                    from include/linux/buildid.h:5,
                    from include/linux/module.h:14,
                    from net/openvswitch/datapath.c:9:
   net/openvswitch/datapath.c: In function 'ovs_flow_cmd_new':
   include/asm-generic/current.h:7:45: error: expected ')' before '->' token
       7 | #define get_current() (current_thread_info()->task)
         |                                             ^~
   include/asm-generic/current.h:8:17: note: in expansion of macro 'get_current'
       8 | #define current get_current()
         |                 ^~~~~~~~~~~
   net/openvswitch/datapath.c:1100:32: note: in expansion of macro 'current'
    1100 |                         size_t current, desired;
         |                                ^~~~~~~
>> net/openvswitch/datapath.c:1102:33: warning: assignment to 'struct task_struct *' from 'size_t' {aka 'unsigned int'} makes pointer from integer without a cast [-Wint-conversion]
    1102 |                         current = ovs_flow_cmd_msg_size(acts, &new_flow->id,
         |                                 ^
   net/openvswitch/datapath.c:1104:25: error: 'desired' undeclared (first use in this function)
    1104 |                         desired = ovs_flow_cmd_msg_size(acts, &flow->id,
         |                         ^~~~~~~
   net/openvswitch/datapath.c:1104:25: note: each undeclared identifier is reported only once for each function it appears in


vim +1102 net/openvswitch/datapath.c

   966	
   967	static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
   968	{
   969		struct net *net = sock_net(skb->sk);
   970		struct nlattr **a = info->attrs;
   971		struct ovs_header *ovs_header = info->userhdr;
   972		struct sw_flow *flow = NULL, *new_flow;
   973		struct sw_flow_mask mask;
   974		struct sk_buff *reply;
   975		struct datapath *dp;
   976		struct sw_flow_key *key;
   977		struct sw_flow_actions *acts;
   978		struct sw_flow_match match;
   979		u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
   980		int error;
   981		bool log = !a[OVS_FLOW_ATTR_PROBE];
   982	
   983		/* Must have key and actions. */
   984		error = -EINVAL;
   985		if (!a[OVS_FLOW_ATTR_KEY]) {
   986			OVS_NLERR(log, "Flow key attr not present in new flow.");
   987			goto error;
   988		}
   989		if (!a[OVS_FLOW_ATTR_ACTIONS]) {
   990			OVS_NLERR(log, "Flow actions attr not present in new flow.");
   991			goto error;
   992		}
   993	
   994		/* Most of the time we need to allocate a new flow, do it before
   995		 * locking.
   996		 */
   997		new_flow = ovs_flow_alloc();
   998		if (IS_ERR(new_flow)) {
   999			error = PTR_ERR(new_flow);
  1000			goto error;
  1001		}
  1002	
  1003		/* Extract key. */
  1004		key = kzalloc(sizeof(*key), GFP_KERNEL);
  1005		if (!key) {
  1006			error = -ENOMEM;
  1007			goto err_kfree_flow;
  1008		}
  1009	
  1010		ovs_match_init(&match, key, false, &mask);
  1011		error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
  1012					  a[OVS_FLOW_ATTR_MASK], log);
  1013		if (error)
  1014			goto err_kfree_key;
  1015	
  1016		ovs_flow_mask_key(&new_flow->key, key, true, &mask);
  1017	
  1018		/* Extract flow identifier. */
  1019		error = ovs_nla_get_identifier(&new_flow->id, a[OVS_FLOW_ATTR_UFID],
  1020					       key, log);
  1021		if (error)
  1022			goto err_kfree_key;
  1023	
  1024		/* Validate actions. */
  1025		error = ovs_nla_copy_actions(net, a[OVS_FLOW_ATTR_ACTIONS],
  1026					     &new_flow->key, &acts, log);
  1027		if (error) {
  1028			OVS_NLERR(log, "Flow actions may not be safe on all matching packets.");
  1029			goto err_kfree_key;
  1030		}
  1031	
  1032		reply = ovs_flow_cmd_alloc_info(acts, &new_flow->id, info, false,
  1033						ufid_flags);
  1034		if (IS_ERR(reply)) {
  1035			error = PTR_ERR(reply);
  1036			goto err_kfree_acts;
  1037		}
  1038	
  1039		ovs_lock();
  1040		dp = get_dp(net, ovs_header->dp_ifindex);
  1041		if (unlikely(!dp)) {
  1042			error = -ENODEV;
  1043			goto err_unlock_ovs;
  1044		}
  1045	
  1046		/* Check if this is a duplicate flow */
  1047		if (ovs_identifier_is_ufid(&new_flow->id))
  1048			flow = ovs_flow_tbl_lookup_ufid(&dp->table, &new_flow->id);
  1049		if (!flow)
  1050			flow = ovs_flow_tbl_lookup(&dp->table, key);
  1051		if (likely(!flow)) {
  1052			rcu_assign_pointer(new_flow->sf_acts, acts);
  1053	
  1054			/* Put flow in bucket. */
  1055			error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
  1056			if (unlikely(error)) {
  1057				acts = NULL;
  1058				goto err_unlock_ovs;
  1059			}
  1060	
  1061			if (unlikely(reply)) {
  1062				error = ovs_flow_cmd_fill_info(new_flow,
  1063							       ovs_header->dp_ifindex,
  1064							       reply, info->snd_portid,
  1065							       info->snd_seq, 0,
  1066							       OVS_FLOW_CMD_NEW,
  1067							       ufid_flags);
  1068				BUG_ON(error < 0);
  1069			}
  1070			ovs_unlock();
  1071		} else {
  1072			struct sw_flow_actions *old_acts;
  1073	
  1074			/* Bail out if we're not allowed to modify an existing flow.
  1075			 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
  1076			 * because Generic Netlink treats the latter as a dump
  1077			 * request.  We also accept NLM_F_EXCL in case that bug ever
  1078			 * gets fixed.
  1079			 */
  1080			if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
  1081								 | NLM_F_EXCL))) {
  1082				error = -EEXIST;
  1083				goto err_unlock_ovs;
  1084			}
  1085	
  1086			/* Look for any overlapping flow. */
  1087			if (unlikely(!ovs_flow_cmp(flow, &match))) {
  1088				if (ovs_identifier_is_key(&flow->id))
  1089					flow = ovs_flow_tbl_lookup_exact(&dp->table,
  1090									 &match);
  1091				else /* UFID matches but key is different */
  1092					flow = NULL;
  1093				if (!flow) {
  1094					error = -ENOENT;
  1095					goto err_unlock_ovs;
  1096				}
  1097			}
  1098	
  1099			if (unlikely(reply)) {
  1100				size_t current, desired;
  1101	
> 1102				current = ovs_flow_cmd_msg_size(acts, &new_flow->id,
  1103								ufid_flags);
  1104				desired = ovs_flow_cmd_msg_size(acts, &flow->id,
  1105								ufid_flags);
  1106				if (current < desired) {
  1107					struct sk_buff *resized;
  1108	
  1109					resized = ovs_flow_cmd_alloc_info(acts, &flow->id,
  1110									  info, false,
  1111									  ufid_flags);
  1112					if (IS_ERR(resized)) {
  1113						error = PTR_ERR(resized);
  1114						goto err_unlock_ovs;
  1115					}
  1116					kfree_skb(reply);
  1117					reply = resized;
  1118				}
  1119			}
  1120	
  1121			/* Update actions. */
  1122			old_acts = ovsl_dereference(flow->sf_acts);
  1123			rcu_assign_pointer(flow->sf_acts, acts);
  1124	
  1125			if (unlikely(reply)) {
  1126				error = ovs_flow_cmd_fill_info(flow,
  1127							       ovs_header->dp_ifindex,
  1128							       reply, info->snd_portid,
  1129							       info->snd_seq, 0,
  1130							       OVS_FLOW_CMD_NEW,
  1131							       ufid_flags);
  1132				BUG_ON(error < 0);
  1133			}
  1134			ovs_unlock();
  1135	
  1136			ovs_nla_free_flow_actions_rcu(old_acts);
  1137			ovs_flow_free(new_flow, false);
  1138		}
  1139	
  1140		if (reply)
  1141			ovs_notify(&dp_flow_genl_family, reply, info);
  1142	
  1143		kfree(key);
  1144		return 0;
  1145	
  1146	err_unlock_ovs:
  1147		ovs_unlock();
  1148		kfree_skb(reply);
  1149	err_kfree_acts:
  1150		ovs_nla_free_flow_actions(acts);
  1151	err_kfree_key:
  1152		kfree(key);
  1153	err_kfree_flow:
  1154		ovs_flow_free(new_flow, false);
  1155	error:
  1156		return error;
  1157	}
  1158	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2026-08-08 22:20 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-08-01 11:25 [PATCH net v4 1/1] net: openvswitch: reallocate update replies for mismatched IDs Zhiling Zou
2026-08-01 15:00 ` Ilya Maximets
2026-08-08 14:23 ` kernel test robot
2026-08-08 17:33 ` kernel test robot
2026-08-08 22:19 ` kernel test robot

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