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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?LlRLQaz7JKw2PQIDs+rsBVzALU66bAIbmdDv0Z2Z8xwUzPSSLiBYJdt0kpvr?= =?us-ascii?Q?UuUZbWvrNe/lHM7dNqSV8mLjr1jj9i1J5nWAuNBk6B/Rq8cBir0aFPpDua1P?= =?us-ascii?Q?0mhnJvmbguLXA4aTiJTUMF2x/dpjNsLtG653IzMFmD61fmnp/Rakx+N+tB2F?= =?us-ascii?Q?V7RdghDqValKsqV1DpVRsNLK68ZGuI5CcloKWGZqfv3wRuDs3M1CK20jRq2P?= =?us-ascii?Q?v6IzMgOYYG0XJxG+kpT4ftwIIyXCffWN7y4bPXHrDTCZ57EGAFNS8hS4kSRG?= =?us-ascii?Q?cXsk1zLpQPPQ5amcSlwnTKtGcgLS1Q4vw5btAoJxeOSHIngIlUp2WH78rVj7?= =?us-ascii?Q?85gdaxSLm1gdtbT6BKLLeCGI1W1SafBoV7eXL3kF7TqWY04uZ+sycKDHFKLs?= =?us-ascii?Q?hTHrslf4B5LKH50TiT9VN/3afzQGhO8IGOSGQHFbqTFMkO6KMNEJWCzvF8UU?= =?us-ascii?Q?K5nNmHx6A9aEovB/VNbOHgJbUiP9Q1/jVDbsmA3NkFEldIOf4pv33HKqKa39?= =?us-ascii?Q?ge+D0cAOYcRTL8v0fQx3hji8I6yLW+i9ONZgaQHq40FSla/QSKKXMxGDMErm?= =?us-ascii?Q?JOSCOziUDB5+R/3HVwN73DNKU6cHWB0VINFBhQmjlfqwALoJGl7yqHdcObQO?= =?us-ascii?Q?NgGt1XI0aTns7bTRMv9gFFXBy6Vrm4cedAOQUZ3dc856Wqc7NMSP487yUwCf?= =?us-ascii?Q?8WccPcdSfWaPuS/T8nFs3jyejmVZT1gc0Sg9F8+VNzbnBxT+PPwNmxENRerk?= =?us-ascii?Q?wQn+JUjX+bqzlVQqzM+cwywU66hpLuOZq066JDZWTqaNSmOVIYcbLv/3Mzd+?= =?us-ascii?Q?xtniuzINyC1JoUJvuMB9eE7cIFr9S2SzbkN3aDPbLU0rv6MQRgSUySCumon6?= =?us-ascii?Q?Aj5eYig+hT+1OOahTjOGfcDKd00XCmQHR/Ykw2b2jUtsiLGXE4En3rRNtaya?= =?us-ascii?Q?vyN1hB4Fri+5kOHwpAlLPRHZ4O4GRFQ5F6HGc2A87YPmFBU0XSa8BynkcPaq?= =?us-ascii?Q?lvztkdLkWekqh9+UCK+WcSMMPmgBS2EBWDzdzT9DlUC4IMIhCdfhnz9Q44F9?= =?us-ascii?Q?w8fIverNhLzN/H8EPrhWtWtOWSMvmYFvzK6aOOHafHTNml34ZAooWoG+wTxj?= =?us-ascii?Q?A/Onepoj9Ir9nlbFOx1xUaCZWJHXmO5iE/aYAlAgAEtmTdmkKmXTS1aaOjEL?= =?us-ascii?Q?mfHjGBY8Abwpy9VYJwfZI16qrV5Yhk0Fcj6/FgjWIDifgV2Z8WKmD54rJGxr?= =?us-ascii?Q?kYfR4ayLjKkGD3przg4VpszYa79biM6wLCKGnkl52lMGPGmWMXibIeTRgDjk?= =?us-ascii?Q?i1pGG95maQoAWox1ayyHGYWtmnXZU/Dy2Hm0+08u8yK/iDqg6g1NJNyMZ4Vw?= =?us-ascii?Q?kOPLiodaROM1x+DGgMZGG6aB0jnsm/KnLUE/Trc+VfhC+PE5DJMTg6L4zvUu?= =?us-ascii?Q?BAPqxjdK0iwXJqGDzzBKUt/aqhftRzvmvGbRlrhb5JPBuVGzbSCbyS4kBYfy?= =?us-ascii?Q?lonK9anAXiVhEWnFfWG+TCK3JUjAVPbcUDVDpfZdqYi81Hb8b2+8Fbe8n2GE?= =?us-ascii?Q?2GuigNRP5UliGoOWpCfuhmRO/2wIO+wP2wn3yMjPD4fFi4+NAJUOxX51N/T8?= =?us-ascii?Q?wQ=3D=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: 7cd0d643-94ee-4ab7-f37b-08db6d86ab8f X-MS-Exchange-CrossTenant-AuthSource: DM4PR11MB6117.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Jun 2023 09:55:37.5763 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 3ky0MDqyA7Zz/VWKAL12DaqJBBYixhC2x1JJ3M6u0JDq5ILNbW6FpbpoEcnymczXUso2n3rL3VeYO5zVi+bfqlxdDs0VUTLq+kY1/AJAG8w= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH0PR11MB5378 X-OriginatorOrg: intel.com X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Thu, Jun 15, 2023 at 11:45:36AM +0200, Simon Horman wrote: Hi Simon, > In igc_clean_rx_irq() the result of a call to igc_xdp_run_prog() is assigned > to the skb local variable. This may be an ERR_PTR. > > A little later the following is executed, which seems to be a > possible dereference of an ERR_PTR. > > total_bytes += skb->len; > > Avoid this problem by continuing the loop in which all of the > above occurs once the handling of the NULL case completes. > > This proposed fix is speculative - I do not have deep knowledge of this > driver. And I am concerned about the effect of skipping the following > logic: > > igc_put_rx_buffer(rx_ring, rx_buffer, rx_buffer_pgcnt); > cleaned_count++; this will break - you have to recycle the buffer to have it going. > > Flagged by Smatch as: > > .../igc_main.c:2467 igc_xdp_run_prog() warn: passing zero to 'ERR_PTR' how about PTR_ERR_OR_ZERO() ? this would silence smatch and is not an intrusive change. another way is to get rid of ERR_PTR() around skb/xdp run result but i think the former would be just fine. > > Compile tested only. > > Fixes: 26575105d6ed ("igc: Add initial XDP support") > Signed-off-by: Simon Horman > --- > drivers/net/ethernet/intel/igc/igc_main.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c > index 88145c30c919..b58c8a674bd1 100644 > --- a/drivers/net/ethernet/intel/igc/igc_main.c > +++ b/drivers/net/ethernet/intel/igc/igc_main.c > @@ -2586,6 +2586,7 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) > > total_packets++; > total_bytes += size; > + continue; > } else if (skb) > igc_add_rx_frag(rx_ring, rx_buffer, skb, size); > else if (ring_uses_build_skb(rx_ring)) > >