[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <202411140905.a0ntnQQG-lkp@intel.com>
Date: Thu, 14 Nov 2024 09:29:42 +0800
From: kernel test robot <lkp@...el.com>
To: Erin Shepherd <erin.shepherd@....eu>,
Christian Brauner <brauner@...nel.org>,
Alexander Viro <viro@...iv.linux.org.uk>, Jan Kara <jack@...e.cz>,
Chuck Lever <chuck.lever@...cle.com>
Cc: oe-kbuild-all@...ts.linux.dev, linux-fsdevel@...r.kernel.org,
linux-kernel@...r.kernel.org, Jeff Layton <jlayton@...nel.org>,
Amir Goldstein <amir73il@...il.com>, linux-nfs@...r.kernel.org,
Erin Shepherd <erin.shepherd@....eu>
Subject: Re: [PATCH v2 2/3] exportfs: allow fs to disable CAP_DAC_READ_SEARCH
check
Hi Erin,
kernel test robot noticed the following build warnings:
[auto build test WARNING on 14b6320953a3f856a3f93bf9a0e423395baa593d]
url: https://github.com/intel-lab-lkp/linux/commits/Erin-Shepherd/pseudofs-add-support-for-export_ops/20241114-020539
base: 14b6320953a3f856a3f93bf9a0e423395baa593d
patch link: https://lore.kernel.org/r/20241113-pidfs_fh-v2-2-9a4d28155a37%40e43.eu
patch subject: [PATCH v2 2/3] exportfs: allow fs to disable CAP_DAC_READ_SEARCH check
config: openrisc-defconfig (https://download.01.org/0day-ci/archive/20241114/202411140905.a0ntnQQG-lkp@intel.com/config)
compiler: or1k-linux-gcc (GCC) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241114/202411140905.a0ntnQQG-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@...el.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202411140905.a0ntnQQG-lkp@intel.com/
All warnings (new ones prefixed by >>):
fs/fhandle.c: In function 'may_decode_fh':
>> fs/fhandle.c:242:41: warning: initialization discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
242 | struct export_operations *nop = root->mnt->mnt_sb->s_export_op;
| ^~~~
vim +/const +242 fs/fhandle.c
237
238 static inline bool may_decode_fh(struct handle_to_path_ctx *ctx,
239 unsigned int o_flags)
240 {
241 struct path *root = &ctx->root;
> 242 struct export_operations *nop = root->mnt->mnt_sb->s_export_op;
243
244 if (nop && nop->flags & EXPORT_OP_UNRESTRICTED_OPEN)
245 return true;
246
247 if (capable(CAP_DAC_READ_SEARCH))
248 return true;
249
250 /*
251 * Allow relaxed permissions of file handles if the caller has the
252 * ability to mount the filesystem or create a bind-mount of the
253 * provided @mountdirfd.
254 *
255 * In both cases the caller may be able to get an unobstructed way to
256 * the encoded file handle. If the caller is only able to create a
257 * bind-mount we need to verify that there are no locked mounts on top
258 * of it that could prevent us from getting to the encoded file.
259 *
260 * In principle, locked mounts can prevent the caller from mounting the
261 * filesystem but that only applies to procfs and sysfs neither of which
262 * support decoding file handles.
263 *
264 * Restrict to O_DIRECTORY to provide a deterministic API that avoids a
265 * confusing api in the face of disconnected non-dir dentries.
266 *
267 * There's only one dentry for each directory inode (VFS rule)...
268 */
269 if (!(o_flags & O_DIRECTORY))
270 return false;
271
272 if (ns_capable(root->mnt->mnt_sb->s_user_ns, CAP_SYS_ADMIN))
273 ctx->flags = HANDLE_CHECK_PERMS;
274 else if (is_mounted(root->mnt) &&
275 ns_capable(real_mount(root->mnt)->mnt_ns->user_ns,
276 CAP_SYS_ADMIN) &&
277 !has_locked_children(real_mount(root->mnt), root->dentry))
278 ctx->flags = HANDLE_CHECK_PERMS | HANDLE_CHECK_SUBTREE;
279 else
280 return false;
281
282 /* Are we able to override DAC permissions? */
283 if (!ns_capable(current_user_ns(), CAP_DAC_READ_SEARCH))
284 return false;
285
286 ctx->fh_flags = EXPORT_FH_DIR_ONLY;
287 return true;
288 }
289
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Powered by blists - more mailing lists