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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?S8Orypi2Sy7jUDY2QT/wRkAtoijU8QajAzxve0+1xNAyaZFzTawcXFrwf3mN?= =?us-ascii?Q?WXuGkN5C8ZOiyCm7gppJ/WW9Mwkvr8Ylro3jZ0WSDNitqyhjhUwQSzl0Sar6?= =?us-ascii?Q?2eZGFTHRFN4rLa9bxh2hbA9tXxEZ1wfGes+o3YPlVngAAAV0zFqchuVJmP8O?= =?us-ascii?Q?evRqEYQ8+QhhRmnydoX1+UwXiZAkBtYA8wKLA9P1XgnfDMWHvOKGd//DsdC3?= =?us-ascii?Q?lwwqwjJdaPm6svOGY3nPneWj5pW5R425Ml+72KjsfE/05zyZxPNXe08wpoBp?= =?us-ascii?Q?XGv2EAKFSuL+HD9DtWfLUU+q0nD9lPOJ/Tk73lZgEBQBFNImgsL2bPRqqRAB?= =?us-ascii?Q?66uGGEXfN7uIgQ3Bdt3gl1tSjnhZRz46zPZH4jZ8odCOBC+zEUAiUgPXyW6v?= =?us-ascii?Q?ep/WQg2RpOc3OtCF+d0ls/UcxoThQDDyQYl5P5tE7I67ie88LLANe2XA/zNV?= =?us-ascii?Q?BzqBaDCg+cjFmE6+R6zfoZ3J5pgHrJIYYqtLoVw/l+WNUp3GyQ1y9HQxQSH7?= =?us-ascii?Q?baivYyejM4nTOTB6gb6UrClan01n1eFWS08oxt+IHIawkT//uVn/qkjO4HK9?= =?us-ascii?Q?Elz+QM53GgI5Cu0CLT7BZ1DZj5d090QYNNILpunirn13XLk75p6018aavl4N?= =?us-ascii?Q?s4MT+2M6a2rb7rfl55SepaizSX8JFBZhT46BWoe4OUXptrVvnWX+40G9/hYL?= =?us-ascii?Q?mLIPnaa334n0fWnGwOl27tiQOJEOjebftIqdTK7Zq7PeBHmI9gePKyvmzPs7?= =?us-ascii?Q?HMHtefSZzMs1IdhD/ZiNpgJbcNEapF05gvsIs+MySediXmEMLrXfTz6lFWVf?= =?us-ascii?Q?sm2wms+LXHNGvIZDyCu7DKJ6WKs+bAv/PaNREcuUP86mOtLez4saHUrL4R/G?= =?us-ascii?Q?l03lFmdhwp/oG5njFHD/ho8Lbvnwa5d0P3Nu2X6vktE17e46o24hUhhMHvns?= =?us-ascii?Q?xr1mwbvENm+ElfAPYL2PzYOKEOPCbltpuWUI2FpvnbXTZfTSuFtWHQ3hfInV?= =?us-ascii?Q?Z8Qu11snQUL1Bd5Aj7651i+Gm0r4rqR1T2uUxqqudVJ1BYyFsSd+N5hng1uw?= =?us-ascii?Q?P0cMU8saLl163MWyPTftyn7fN5YcUxO/gWnARHGO8hTkynMhTBkSrj7NYFHU?= =?us-ascii?Q?+fNnVB6GdhQrfgqPqVbm6AKbsPLEau7nsq/gHOUA0zy5/5/FOqSzMaeajx9s?= =?us-ascii?Q?TpYkcfDgCUF5v3nXm9tqdtnOyRXqIsukMYFRbpoUNTrY89PphFeUb0cfznrl?= =?us-ascii?Q?6N+FviYOrTjii/lt5vkt/4GrMANevWS3thSI/svSUVzZsxrloeqtU3WUYYdw?= =?us-ascii?Q?UjyvCbmfGENV6NuocZC6VrUtAYA0K4IbeCnJUQJJlPYGkNqCwJ560n3liGEC?= =?us-ascii?Q?wUkSnNK5SSxQu4KuVoINZ9xw5cSb9bSMnOoDjnDW+P/CcWxkjJRn3PBsRxZO?= =?us-ascii?Q?APtuIlGm+cbUxIXwgsrBVCYm2QFgFjOlL3XpklhFadlRHKdgY90vS/k2Ndzj?= =?us-ascii?Q?Ifd8jWtO/TB+/K27tRpwniNk5WY9I8ISGTAmd0VTqen1lICckc07vdqmPu47?= =?us-ascii?Q?l0fO0ucpnPVWQAQqAafYhWpuerwOU6hgDbPFct6s?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d77d9716-b4f7-4e56-826c-08dd8c6833ba X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 May 2025 06:35:33.0397 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: oIB2/IRi3xc+iR+wqFw3/aW/eVb39TPHFNS96ctd/eFMx5OcuWIMGhxCC6vmdYpHuODU42UR/o33PGafYYb2Kg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV8PR12MB9205 On Mon, May 05, 2025 at 11:30:39AM -1000, Tejun Heo wrote: > From 3ca42b7aea35cbcfb8d1fdde09e10a54edf97b26 Mon Sep 17 00:00:00 2001 > From: Tejun Heo > Date: Mon, 5 May 2025 11:28:21 -1000 > > BPF programs may call next() and destroy() on BPF iterators even after new() > returns an error value. bpf_iter_scx_dsq_new() could leave the iterator in > an uninitialized state after an error return causing bpf_iter_scx_dsq_next() > to dereference garbage data. Make bpf_iter_scx_dsq_new() always clear > $kit->dsq so that next() and destroy() become noops. > > Signed-off-by: Tejun Heo > Fixes: 650ba21b131e ("sched_ext: Implement DSQ iterator") > Cc: stable@vger.kernel.org # v6.12+ > --- > kernel/sched/ext.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c > index 4e37b40ce280..f5133249fd4d 100644 > --- a/kernel/sched/ext.c > +++ b/kernel/sched/ext.c > @@ -6827,6 +6827,12 @@ __bpf_kfunc int bpf_iter_scx_dsq_new(struct bpf_iter_scx_dsq *it, u64 dsq_id, > BUILD_BUG_ON(__alignof__(struct bpf_iter_scx_dsq_kern) != > __alignof__(struct bpf_iter_scx_dsq)); > > + /* > + * next() and destroy() will be called regardless of the return value. > + * Always clear $kit->dsq. Nit (feel free to ignore): we could mention that bpf_for_each() is the one calling next() and destroy(), but overall looks good to me. Acked-by: Andrea Righi Thanks, -Andrea > + */ > + kit->dsq = NULL; > + > if (flags & ~__SCX_DSQ_ITER_USER_FLAGS) > return -EINVAL; > > -- > 2.49.0