From patchwork Wed Dec 13 23:24:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilya Leoshkevich X-Patchwork-Id: 13492087 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="rti6Izmv" Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F306910A; Wed, 13 Dec 2023 15:36:56 -0800 (PST) Received: from pps.filterd (m0353725.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3BDNWpG0008639; Wed, 13 Dec 2023 23:36:37 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=kALH6Y40PszMAinDNJqUOT92xkYCLa2PA86QJ0JSv5E=; b=rti6IzmvgbsZRjEVeEO1xXvE5pE073L2SYCZ3ZV01QYSF42RcR7ebu8vD2jRYzkQtXw5 +O6U2ydu4p1TuIwsNLP+vZyVYfYFfgQWDJo7R6dJpYlC7lircnWjz0CfJO5mjBKVkWjK BPxWsgF37h1WKIzZzVZxQAUv8LCOqN5aD3SIpA4NtXXEIXPfJTFrVdb0jXXvRjjx66aa EtPawQFf1/kgV1dsNJJNtOotYqGFxBf7IhPnzxzLnxgYq5RSP0qaZNtfpVRJIzoxa/CT wNP/icCT57ZYwxne1b6oPTUEHe35U6bvvZdKEn16MZ+ZA4bHiztVwAuLRyC6nm3sgCmW KA== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3uypce81tm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 13 Dec 2023 23:36:37 +0000 Received: from m0353725.ppops.net (m0353725.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3BDNaaPI017559; Wed, 13 Dec 2023 23:36:36 GMT Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3uypce81sp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 13 Dec 2023 23:36:36 +0000 Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 3BDKwk1X008585; Wed, 13 Dec 2023 23:36:29 GMT Received: from smtprelay03.fra02v.mail.ibm.com ([9.218.2.224]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 3uw2jtmvkk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 13 Dec 2023 23:36:29 +0000 Received: from smtpav02.fra02v.mail.ibm.com (smtpav02.fra02v.mail.ibm.com [10.20.54.101]) by smtprelay03.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 3BDNaR9V20906592 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 13 Dec 2023 23:36:27 GMT Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E149B2004B; Wed, 13 Dec 2023 23:36:26 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7B4F320040; Wed, 13 Dec 2023 23:36:25 +0000 (GMT) Received: from heavy.boeblingen.de.ibm.com (unknown [9.171.70.156]) by smtpav02.fra02v.mail.ibm.com (Postfix) with ESMTP; Wed, 13 Dec 2023 23:36:25 +0000 (GMT) From: Ilya Leoshkevich To: Alexander Gordeev , Alexander Potapenko , Andrew Morton , Christoph Lameter , David Rientjes , Heiko Carstens , Joonsoo Kim , Marco Elver , Masami Hiramatsu , Pekka Enberg , Steven Rostedt , Vasily Gorbik , Vlastimil Babka Cc: Christian Borntraeger , Dmitry Vyukov , Hyeonggon Yoo <42.hyeyoo@gmail.com>, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-s390@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Mark Rutland , Roman Gushchin , Sven Schnelle , Ilya Leoshkevich Subject: [PATCH v3 11/34] kmsan: Allow disabling KMSAN checks for the current task Date: Thu, 14 Dec 2023 00:24:31 +0100 Message-ID: <20231213233605.661251-12-iii@linux.ibm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231213233605.661251-1-iii@linux.ibm.com> References: <20231213233605.661251-1-iii@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: jBznlbH2FEtEOu-Pu04xnJahDcCOZLZZ X-Proofpoint-ORIG-GUID: is7ZIVg49ekM5OZcy2r9v7nHMXQ7PWe1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-12-13_14,2023-12-13_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 mlxlogscore=999 lowpriorityscore=0 adultscore=0 phishscore=0 mlxscore=0 suspectscore=0 priorityscore=1501 clxscore=1015 spamscore=0 impostorscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311290000 definitions=main-2312130167 Like for KASAN, it's useful to temporarily disable KMSAN checks around, e.g., redzone accesses. Introduce kmsan_disable_current() and kmsan_enable_current(), which are similar to their KASAN counterparts. Make them reentrant in order to handle memory allocations in interrupt context. Repurpose the allow_reporting field for this. Signed-off-by: Ilya Leoshkevich --- Documentation/dev-tools/kmsan.rst | 4 ++-- include/linux/kmsan.h | 24 ++++++++++++++++++++++++ include/linux/kmsan_types.h | 2 +- mm/kmsan/core.c | 1 - mm/kmsan/hooks.c | 18 +++++++++++++++--- mm/kmsan/report.c | 7 ++++--- 6 files changed, 46 insertions(+), 10 deletions(-) diff --git a/Documentation/dev-tools/kmsan.rst b/Documentation/dev-tools/kmsan.rst index 323eedad53cd..022a823f5f1b 100644 --- a/Documentation/dev-tools/kmsan.rst +++ b/Documentation/dev-tools/kmsan.rst @@ -338,11 +338,11 @@ Per-task KMSAN state ~~~~~~~~~~~~~~~~~~~~ Every task_struct has an associated KMSAN task state that holds the KMSAN -context (see above) and a per-task flag disallowing KMSAN reports:: +context (see above) and a per-task counter disallowing KMSAN reports:: struct kmsan_context { ... - bool allow_reporting; + unsigned int depth; struct kmsan_context_state cstate; ... } diff --git a/include/linux/kmsan.h b/include/linux/kmsan.h index fe6c2212bdb1..23de1b3d6aee 100644 --- a/include/linux/kmsan.h +++ b/include/linux/kmsan.h @@ -239,6 +239,22 @@ void kmsan_unpoison_entry_regs(const struct pt_regs *regs); */ void *kmsan_get_metadata(void *addr, bool is_origin); +/* + * kmsan_enable_current(): Enable KMSAN for the current task. + * + * Each kmsan_enable_current() current call must be preceded by a + * kmsan_disable_current() call. These call pairs may be nested. + */ +void kmsan_enable_current(void); + +/* + * kmsan_disable_current(): Disable KMSAN for the current task. + * + * Each kmsan_disable_current() current call must be followed by a + * kmsan_enable_current() call. These call pairs may be nested. + */ +void kmsan_disable_current(void); + #else static inline void kmsan_init_shadow(void) @@ -338,6 +354,14 @@ static inline void kmsan_unpoison_entry_regs(const struct pt_regs *regs) { } +static inline void kmsan_enable_current(void) +{ +} + +static inline void kmsan_disable_current(void) +{ +} + #endif #endif /* _LINUX_KMSAN_H */ diff --git a/include/linux/kmsan_types.h b/include/linux/kmsan_types.h index 8bfa6c98176d..27bb146ece95 100644 --- a/include/linux/kmsan_types.h +++ b/include/linux/kmsan_types.h @@ -29,7 +29,7 @@ struct kmsan_context_state { struct kmsan_ctx { struct kmsan_context_state cstate; int kmsan_in_runtime; - bool allow_reporting; + unsigned int depth; }; #endif /* _LINUX_KMSAN_TYPES_H */ diff --git a/mm/kmsan/core.c b/mm/kmsan/core.c index c19f47af0424..68c68b30441d 100644 --- a/mm/kmsan/core.c +++ b/mm/kmsan/core.c @@ -43,7 +43,6 @@ void kmsan_internal_task_create(struct task_struct *task) struct thread_info *info = current_thread_info(); __memset(ctx, 0, sizeof(*ctx)); - ctx->allow_reporting = true; kmsan_internal_unpoison_memory(info, sizeof(*info), false); } diff --git a/mm/kmsan/hooks.c b/mm/kmsan/hooks.c index eafc45f937eb..3acf010c9814 100644 --- a/mm/kmsan/hooks.c +++ b/mm/kmsan/hooks.c @@ -39,12 +39,10 @@ void kmsan_task_create(struct task_struct *task) void kmsan_task_exit(struct task_struct *task) { - struct kmsan_ctx *ctx = &task->kmsan_ctx; - if (!kmsan_enabled || kmsan_in_runtime()) return; - ctx->allow_reporting = false; + kmsan_disable_current(); } void kmsan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags) @@ -423,3 +421,17 @@ void kmsan_check_memory(const void *addr, size_t size) REASON_ANY); } EXPORT_SYMBOL(kmsan_check_memory); + +void kmsan_enable_current(void) +{ + KMSAN_WARN_ON(current->kmsan_ctx.depth == 0); + current->kmsan_ctx.depth--; +} +EXPORT_SYMBOL(kmsan_enable_current); + +void kmsan_disable_current(void) +{ + current->kmsan_ctx.depth++; + KMSAN_WARN_ON(current->kmsan_ctx.depth == 0); +} +EXPORT_SYMBOL(kmsan_disable_current); diff --git a/mm/kmsan/report.c b/mm/kmsan/report.c index c79d3b0d2d0d..92e73ec61435 100644 --- a/mm/kmsan/report.c +++ b/mm/kmsan/report.c @@ -8,6 +8,7 @@ */ #include +#include #include #include #include @@ -158,12 +159,12 @@ void kmsan_report(depot_stack_handle_t origin, void *address, int size, if (!kmsan_enabled) return; - if (!current->kmsan_ctx.allow_reporting) + if (current->kmsan_ctx.depth) return; if (!origin) return; - current->kmsan_ctx.allow_reporting = false; + kmsan_disable_current(); ua_flags = user_access_save(); raw_spin_lock(&kmsan_report_lock); pr_err("=====================================================\n"); @@ -216,5 +217,5 @@ void kmsan_report(depot_stack_handle_t origin, void *address, int size, if (panic_on_kmsan) panic("kmsan.panic set ...\n"); user_access_restore(ua_flags); - current->kmsan_ctx.allow_reporting = true; + kmsan_enable_current(); }