From nobody Wed Sep 10 05:33:55 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 066B62798FD; Fri, 5 Sep 2025 19:24:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757100268; cv=none; b=ls/ry5Dod1+EAJhrQ1ghcC934MlShTdZ9gNdaO2+l9EqQj9gpDS9AulSVU56FuPupbTfWZby+3qT9m3+gpX1VvuX0t1VD5ERUTLprZioUJuJIbb7n/M6FeiefONMFuUx6JCuTq1jH+JddrfCeZj/N72aGtD/ZGDNGVyUp672lPE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757100268; c=relaxed/simple; bh=PneSr0UFkyje7hiRxdgfda0/0faF4NUEJ+o+j1qL+sc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=hNK/ww4k5rfe3NHZZZP9YXNS5p6lpksdsXSUvYOJLNfG6i/8FoSz1f6zrbo7DQ79zkZPytgcRO/x73c/cN7U7X2q+tqsZ5egkjh3j7IWKPFiF7q3AAFBgBGvfPVHGacWXO0QN8YOzkJ+/DiWxWETcYCL3u1Ywu3/zMxvRpZpSdg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WFuPcJc0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WFuPcJc0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22400C4CEF1; Fri, 5 Sep 2025 19:24:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757100267; bh=PneSr0UFkyje7hiRxdgfda0/0faF4NUEJ+o+j1qL+sc=; h=From:Date:Subject:To:Cc:From; b=WFuPcJc0u1IB0G+xb6m54A2SVprt+VURztyXSXsOtv6TQZnjptkXW00SV5sqwpvmS J1omyhIE9VkmYjYz9RypCZES6Rn7i62OCf+SY1rr/A2Zi80lI5NfMqqJ4D8uI+tpQ6 wLwPVciyTL915kWOBYVjwmW3ckYe+WR+9+P1siOV7Wqtul8PlyAExP/LVUZDWaHHnX GoQj7ODF1f3S0AAY20XKl2G3Uc8yTAEzZwBnLNEhWSVccpZ02Chesl2TshAMS08zN7 T3tO3VA85anwXcenlxKlGjWxUNhWtzKgkpeOrAOfoKATdTMAQPBlRuguONXEjVYefk nGJzVSS/CFm4w== From: Nathan Chancellor Date: Fri, 05 Sep 2025 12:24:17 -0700 Subject: [PATCH] nilfs2: fix CFI failure when accessing /sys/fs/nilfs2/features/* Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250905-nilfs2-fix-features-cfi-violation-v1-1-b5d35136d813@kernel.org> X-B4-Tracking: v=1; b=H4sIAOA4u2gC/x2NQQqDQAxFryJZNxBHBtGrFBepZjQgY5lYKYh3N 7h88N9/J5gUFYO+OqHIoaZbdqhfFYwL51lQJ2cIFCJ1FDHrmixg0j8m4f1XxHBMioduK+9uY8O xkU8M3BKB/3yL+PppvIfrugEy5dlvcwAAAA== X-Change-ID: 20250905-nilfs2-fix-features-cfi-violation-3a53eb52a700 To: Ryusuke Konishi Cc: Kees Cook , linux-nilfs@vger.kernel.org, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel test robot , Nathan Chancellor X-Mailer: b4 0.15-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=3674; i=nathan@kernel.org; h=from:subject:message-id; bh=PneSr0UFkyje7hiRxdgfda0/0faF4NUEJ+o+j1qL+sc=; b=owGbwMvMwCUmm602sfCA1DTG02pJDBm7LV5O75mxwrtSTGB7lt4OySaL1axT1hyo3X23TPHVj zSXNUtvd5SyMIhxMciKKbJUP1Y9bmg45yzjjVOTYOawMoEMYeDiFICJfHjK8FdyqecGt+93zgof WWk4/esd/vmzVDu/7qrn84kRerXXc9sLhn96lipyE1R2aex6MTleduPdM0tnt1lmKTZNk7hVosz 5pJEFAA== X-Developer-Key: i=nathan@kernel.org; a=openpgp; fpr=2437CB76E544CB6AB3D9DFD399739260CB6CB716 When accessing one of the files under /sys/fs/nilfs2/features when CONFIG_CFI_CLANG is enabled, there is a CFI violation: CFI failure at kobj_attr_show+0x59/0x80 (target: nilfs_feature_revision_s= how+0x0/0x30; expected type: 0xfc392c4d) ... Call Trace: sysfs_kf_seq_show+0x2a6/0x390 ? __cfi_kobj_attr_show+0x10/0x10 kernfs_seq_show+0x104/0x15b seq_read_iter+0x580/0xe2b ... When the kobject of the kset for /sys/fs/nilfs2 is initialized, its ktype is set to kset_ktype, which has a ->sysfs_ops of kobj_sysfs_ops. When nilfs_feature_attr_group is added to that kobject via sysfs_create_group(), the kernfs_ops of each files is sysfs_file_kfops_rw, which will call sysfs_kf_seq_show() when ->seq_show() is called. sysfs_kf_seq_show() in turn calls kobj_attr_show() through ->sysfs_ops->show(). kobj_attr_show() casts the provided attribute out to a 'struct kobj_attribute' via container_of() and calls ->show(), resulting in the CFI violation since neither nilfs_feature_revision_show() nor nilfs_feature_README_show() match the prototype of ->show() in 'struct kobj_attribute'. Resolve the CFI violation by adjusting the second parameter in nilfs_feature_{revision,README}_show() from 'struct attribute' to 'struct kobj_attribute' to match the expected prototype. Cc: stable@vger.kernel.org Fixes: aebe17f68444 ("nilfs2: add /sys/fs/nilfs2/features group") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202509021646.bc78d9ef-lkp@intel.com/ Signed-off-by: Nathan Chancellor --- fs/nilfs2/sysfs.c | 4 ++-- fs/nilfs2/sysfs.h | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/fs/nilfs2/sysfs.c b/fs/nilfs2/sysfs.c index 14868a3dd592..bc52afbfc5c7 100644 --- a/fs/nilfs2/sysfs.c +++ b/fs/nilfs2/sysfs.c @@ -1075,7 +1075,7 @@ void nilfs_sysfs_delete_device_group(struct the_nilfs= *nilfs) ************************************************************************/ =20 static ssize_t nilfs_feature_revision_show(struct kobject *kobj, - struct attribute *attr, char *buf) + struct kobj_attribute *attr, char *buf) { return sysfs_emit(buf, "%d.%d\n", NILFS_CURRENT_REV, NILFS_MINOR_REV); @@ -1087,7 +1087,7 @@ static const char features_readme_str[] =3D "(1) revision\n\tshow current revision of NILFS file system driver.\n"; =20 static ssize_t nilfs_feature_README_show(struct kobject *kobj, - struct attribute *attr, + struct kobj_attribute *attr, char *buf) { return sysfs_emit(buf, features_readme_str); diff --git a/fs/nilfs2/sysfs.h b/fs/nilfs2/sysfs.h index 78a87a016928..d370cd5cce3f 100644 --- a/fs/nilfs2/sysfs.h +++ b/fs/nilfs2/sysfs.h @@ -50,16 +50,16 @@ struct nilfs_sysfs_dev_subgroups { struct completion sg_segments_kobj_unregister; }; =20 -#define NILFS_COMMON_ATTR_STRUCT(name) \ +#define NILFS_KOBJ_ATTR_STRUCT(name) \ struct nilfs_##name##_attr { \ struct attribute attr; \ - ssize_t (*show)(struct kobject *, struct attribute *, \ + ssize_t (*show)(struct kobject *, struct kobj_attribute *, \ char *); \ - ssize_t (*store)(struct kobject *, struct attribute *, \ + ssize_t (*store)(struct kobject *, struct kobj_attribute *, \ const char *, size_t); \ } =20 -NILFS_COMMON_ATTR_STRUCT(feature); +NILFS_KOBJ_ATTR_STRUCT(feature); =20 #define NILFS_DEV_ATTR_STRUCT(name) \ struct nilfs_##name##_attr { \ --- base-commit: b320789d6883cc00ac78ce83bccbfe7ed58afcf0 change-id: 20250905-nilfs2-fix-features-cfi-violation-3a53eb52a700 Best regards, -- =20 Nathan Chancellor