From patchwork Fri Feb 7 15:46:39 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 13965331 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 4D7AB24817F; Fri, 7 Feb 2025 15:46:56 +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=1738943217; cv=none; b=EVAy8lDqZRSDDoTA1FpvbVYBqbhSMQdD1wuDxpPxsK0wMcdFGduuO+G+O9XAnuvZgljV0mZpPw4q4mVcdlnyRU1pS7/TfmGjuIdpd/kyTA9UdIB3pfKKJbjRwf9oinT5oaOnw6ywbIPiIz9IenfV9ubsFDcghYYVQz+pz5rnDao= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738943217; c=relaxed/simple; bh=P42K1GRagtuM4ndm7X1Qeq6DLr8cl569VusbGO0FnfY=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=B/p4N24YRqqAoTheey6vaezxwiIc4wcRuPVKf4Nx1f836/GwQx/7JSmrQPEbs02tW5yuwcr/e8nmEIsqRst5CalaFoc6RcSXIzBjaOr/6qpSY1b8O8ePu5dP5iPUI7K6Q/9g9p7X/Cn5zwSEtnrHON2TCMX8PRrmcLMLG/McKpo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Psz3MFn7; 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="Psz3MFn7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5C5CCC4CEEB; Fri, 7 Feb 2025 15:46:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1738943216; bh=P42K1GRagtuM4ndm7X1Qeq6DLr8cl569VusbGO0FnfY=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=Psz3MFn7mdl9vi6vMvf7wrqwn1imT05iTZ+64ijjZ1kOvN6j/uP3EO73cn5Q2HR1W 63HOMMk7t9RkR8n4YMm9QCT6xuTCb1wLIQsZqDh32h+gFEs1B6VAIxJlx+BKrPjRz5 Xc5lULg99seZkZlTI9x7tUM+09feT3dUA1yWY80FQuu+aJTZO8NO5NVVaOEaHdxdiM TI612m51tAtHF+E1/aGAXIeNwlwn+goJBdMxLEzOUsu8pbzxgWPTTPEXenn2rZoObf DZepP5Z73Z0fuzwlrn8PkLJYI8tgT9ClY6SI2ZkHveGYhzMX8GIQRu1Zf9HOjw+1oI bf0tUkLQs+Xcg== From: Christian Brauner Date: Fri, 07 Feb 2025 16:46:39 +0100 Subject: [PATCH 1/2] fs: support O_PATH fds with FSCONFIG_SET_FD Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250207-work-overlayfs-v1-1-611976e73373@kernel.org> References: <20250207-work-overlayfs-v1-0-611976e73373@kernel.org> In-Reply-To: <20250207-work-overlayfs-v1-0-611976e73373@kernel.org> To: linux-unionfs@vger.kernel.org Cc: Miklos Szeredi , Amir Goldstein , Mike Baynton , linux-fsdevel@vger.kernel.org, Christian Brauner X-Mailer: b4 0.15-dev-d23a9 X-Developer-Signature: v=1; a=openpgp-sha256; l=5650; i=brauner@kernel.org; h=from:subject:message-id; bh=P42K1GRagtuM4ndm7X1Qeq6DLr8cl569VusbGO0FnfY=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMaQv03rzKe1esfUlyWJnfm21KW7vJ/HsTHUrfDTDXMAk4 EBC/MNLHaUsDGJcDLJiiiwO7Sbhcst5KjYbZWrAzGFlAhnCwMUpABOZbMbwV+IYd8D5gqlLjR/+ sJ++Sfyo9N+iW9LhG/83bnvI7byEvYvhn40Yl29FfLrgbvc1gozVjX7JZze3ch074xL+aJnwgif 9PAA= X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Let FSCONFIG_SET_FD handle O_PATH file descriptors. This is particularly useful in the context of overlayfs where layers can be specified via file descriptors instead of paths. But userspace must currently use non-O_PATH file desriptors which is often pointless especially if the file descriptors have been created via open_tree(OPEN_TREE_CLONE). Signed-off-by: Christian Brauner --- fs/fs_parser.c | 12 +++++++----- fs/fsopen.c | 7 +++++-- fs/overlayfs/params.c | 10 ++++++---- include/linux/fs_context.h | 1 + include/linux/fs_parser.h | 6 +++--- 5 files changed, 22 insertions(+), 14 deletions(-) diff --git a/fs/fs_parser.c b/fs/fs_parser.c index e635a81e17d9..35aaea224007 100644 --- a/fs/fs_parser.c +++ b/fs/fs_parser.c @@ -310,15 +310,17 @@ int fs_param_is_fd(struct p_log *log, const struct fs_parameter_spec *p, } EXPORT_SYMBOL(fs_param_is_fd); -int fs_param_is_file_or_string(struct p_log *log, - const struct fs_parameter_spec *p, - struct fs_parameter *param, - struct fs_parse_result *result) +int fs_param_is_raw_file_or_string(struct p_log *log, + const struct fs_parameter_spec *p, + struct fs_parameter *param, + struct fs_parse_result *result) { switch (param->type) { case fs_value_is_string: return fs_param_is_string(log, p, param, result); case fs_value_is_file: + fallthrough; + case fs_value_is_raw_file: result->uint_32 = param->dirfd; if (result->uint_32 <= INT_MAX) return 0; @@ -328,7 +330,7 @@ int fs_param_is_file_or_string(struct p_log *log, } return fs_param_bad_value(log, param); } -EXPORT_SYMBOL(fs_param_is_file_or_string); +EXPORT_SYMBOL(fs_param_is_raw_file_or_string); int fs_param_is_uid(struct p_log *log, const struct fs_parameter_spec *p, struct fs_parameter *param, struct fs_parse_result *result) diff --git a/fs/fsopen.c b/fs/fsopen.c index 094a7f510edf..3b5fc9f1f774 100644 --- a/fs/fsopen.c +++ b/fs/fsopen.c @@ -451,11 +451,14 @@ SYSCALL_DEFINE5(fsconfig, param.size = strlen(param.name->name); break; case FSCONFIG_SET_FD: - param.type = fs_value_is_file; ret = -EBADF; - param.file = fget(aux); + param.file = fget_raw(aux); if (!param.file) goto out_key; + if (param.file->f_mode & FMODE_PATH) + param.type = fs_value_is_raw_file; + else + param.type = fs_value_is_file; param.dirfd = aux; break; default: diff --git a/fs/overlayfs/params.c b/fs/overlayfs/params.c index 1115c22deca0..846afa6081a5 100644 --- a/fs/overlayfs/params.c +++ b/fs/overlayfs/params.c @@ -141,10 +141,10 @@ static int ovl_verity_mode_def(void) const struct fs_parameter_spec ovl_parameter_spec[] = { fsparam_string_empty("lowerdir", Opt_lowerdir), - fsparam_file_or_string("lowerdir+", Opt_lowerdir_add), - fsparam_file_or_string("datadir+", Opt_datadir_add), - fsparam_file_or_string("upperdir", Opt_upperdir), - fsparam_file_or_string("workdir", Opt_workdir), + fsparam_raw_file_or_string("lowerdir+", Opt_lowerdir_add), + fsparam_raw_file_or_string("datadir+", Opt_datadir_add), + fsparam_raw_file_or_string("upperdir", Opt_upperdir), + fsparam_raw_file_or_string("workdir", Opt_workdir), fsparam_flag("default_permissions", Opt_default_permissions), fsparam_enum("redirect_dir", Opt_redirect_dir, ovl_parameter_redirect_dir), fsparam_enum("index", Opt_index, ovl_parameter_bool), @@ -438,6 +438,8 @@ static int ovl_parse_layer(struct fs_context *fc, struct fs_parameter *param, return err; err = ovl_do_parse_layer(fc, param->string, &layer_path, layer); break; + case fs_value_is_raw_file: + fallthrough; case fs_value_is_file: { char *buf __free(kfree); char *layer_name; diff --git a/include/linux/fs_context.h b/include/linux/fs_context.h index 4b4bfef6f053..4ba18211046e 100644 --- a/include/linux/fs_context.h +++ b/include/linux/fs_context.h @@ -55,6 +55,7 @@ enum fs_value_type { fs_value_is_blob, /* Value is a binary blob */ fs_value_is_filename, /* Value is a filename* + dirfd */ fs_value_is_file, /* Value is a file* */ + fs_value_is_raw_file, /* Value is an O_PATH/FMODE_PATH file* */ }; /* diff --git a/include/linux/fs_parser.h b/include/linux/fs_parser.h index 53e566efd5fd..77d5d3c78d39 100644 --- a/include/linux/fs_parser.h +++ b/include/linux/fs_parser.h @@ -29,7 +29,7 @@ typedef int fs_param_type(struct p_log *, fs_param_type fs_param_is_bool, fs_param_is_u32, fs_param_is_s32, fs_param_is_u64, fs_param_is_enum, fs_param_is_string, fs_param_is_blob, fs_param_is_blockdev, fs_param_is_path, fs_param_is_fd, fs_param_is_uid, fs_param_is_gid, - fs_param_is_file_or_string; + fs_param_is_raw_file_or_string; /* * Specification of the type of value a parameter wants. @@ -136,8 +136,8 @@ static inline bool fs_validate_description(const char *name, #define fsparam_bdev(NAME, OPT) __fsparam(fs_param_is_blockdev, NAME, OPT, 0, NULL) #define fsparam_path(NAME, OPT) __fsparam(fs_param_is_path, NAME, OPT, 0, NULL) #define fsparam_fd(NAME, OPT) __fsparam(fs_param_is_fd, NAME, OPT, 0, NULL) -#define fsparam_file_or_string(NAME, OPT) \ - __fsparam(fs_param_is_file_or_string, NAME, OPT, 0, NULL) +#define fsparam_raw_file_or_string(NAME, OPT) \ + __fsparam(fs_param_is_raw_file_or_string, NAME, OPT, 0, NULL) #define fsparam_uid(NAME, OPT) __fsparam(fs_param_is_uid, NAME, OPT, 0, NULL) #define fsparam_gid(NAME, OPT) __fsparam(fs_param_is_gid, NAME, OPT, 0, NULL)