From: Andreas Gruenbacher <andreas.gruenbacher@gmail.com>
To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-nfs@vger.kernel.org
Subject: [RFC v3 19/45] richacl: Also recognize nontrivial mode-equivalent acls
Date: Fri, 24 Apr 2015 13:04:16 +0200 [thread overview]
Message-ID: <5e9ee3b123b3d648487cd18dc906b6a2cd23085b.1429868795.git.agruenba@redhat.com> (raw)
In-Reply-To: <cover.1429868795.git.agruenba@redhat.com>
In-Reply-To: <cover.1429868795.git.agruenba@redhat.com>
So far, richacl_equiv_mode() is relatively limited in the types of acl it
considers equivalent to a file mode: it only accepts masked acls with a single
everyone@:rwpxd::allow entry.
Change this to consider all acls equivalent to file modes if they only consist
of owner@, group@, and everyone@ entries and the owner@ permissions do not
depend on whether the owner is a member in the owning group.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
---
fs/richacl_base.c | 150 ++++++++++++++++++++++++++++++++++++++----------
include/linux/richacl.h | 1 +
2 files changed, 122 insertions(+), 29 deletions(-)
diff --git a/fs/richacl_base.c b/fs/richacl_base.c
index db27542..54cb482 100644
--- a/fs/richacl_base.c
+++ b/fs/richacl_base.c
@@ -439,49 +439,141 @@ richacl_inherit(const struct richacl *dir_acl, int isdir)
}
/**
- * richacl_equiv_mode - check if @acl is equivalent to file permission bits
- * @mode_p: the file mode (including the file type)
+ * __richacl_equiv_mode - compute the mode equivalent of @acl
*
- * If @acl can be fully represented by file permission bits, this function
- * returns 0, and the file permission bits in @mode_p are set to the equivalent
- * of @acl.
+ * This function does not consider the masks in @acl.
*
- * This function is used to avoid storing richacls on disk if the acl can be
- * computed from the file permission bits. It allows user-space to make sure
- * that a file has no explicit richacl set.
+ * An acl is considered equivalent to a file mode if it only consists of
+ * owner@, group@, and everyone@ entries and the owner@ permissions do not
+ * depend on whether the owner is a member in the owning group.
*/
int
-richacl_equiv_mode(const struct richacl *acl, mode_t *mode_p)
+__richacl_equiv_mode(const struct richacl *acl, mode_t *mode_p)
{
- const struct richace *ace = acl->a_entries;
- unsigned int x;
- mode_t mask;
-
- if (acl->a_count != 1 ||
- acl->a_flags != RICHACL_MASKED ||
- !richace_is_everyone(ace) ||
- !richace_is_allow(ace) ||
- ace->e_flags & ~RICHACE_SPECIAL_WHO)
+ mode_t mode = *mode_p;
+
+ /*
+ * The RICHACE_DELETE_CHILD flag is meaningless for non-directories, so
+ * we ignore it.
+ */
+ unsigned int x = S_ISDIR(mode) ? 0 : RICHACE_DELETE_CHILD;
+ struct {
+ unsigned int allowed;
+ unsigned int defined; /* allowed or denied */
+ } owner = {
+ .allowed = RICHACE_POSIX_ALWAYS_ALLOWED,
+ .defined = RICHACE_POSIX_ALWAYS_ALLOWED | RICHACE_POSIX_OWNER_ALLOWED | x,
+ }, group = {
+ .allowed = RICHACE_POSIX_ALWAYS_ALLOWED,
+ .defined = RICHACE_POSIX_ALWAYS_ALLOWED | x,
+ }, everyone = {
+ .allowed = RICHACE_POSIX_ALWAYS_ALLOWED,
+ .defined = RICHACE_POSIX_ALWAYS_ALLOWED | x,
+ };
+ const struct richace *ace;
+
+ richacl_for_each_entry(ace, acl) {
+ if (ace->e_flags & ~RICHACE_SPECIAL_WHO)
+ return -1;
+
+ if (richace_is_owner(ace) || richace_is_everyone(ace)) {
+ x = ace->e_mask & ~owner.defined;
+ if (richace_is_allow(ace)) {
+ unsigned int group_denied = group.defined & ~group.allowed;
+
+ if (x & group_denied)
+ return -1;
+ owner.allowed |= x;
+ } else /* if (richace_is_deny(ace)) */ {
+ if (x & group.allowed)
+ return -1;
+ }
+ owner.defined |= x;
+
+ if (richace_is_everyone(ace)) {
+ x = ace->e_mask;
+ if (richace_is_allow(ace)) {
+ group.allowed |= x & ~group.defined;
+ everyone.allowed |= x & ~everyone.defined;
+ }
+ group.defined |= x;
+ everyone.defined |= x;
+ }
+ } else if (richace_is_group(ace)) {
+ x = ace->e_mask & ~group.defined;
+ if (richace_is_allow(ace))
+ group.allowed |= x;
+ group.defined |= x;
+ } else
+ return -1;
+ }
+
+ if (group.allowed & ~owner.defined)
return -1;
- /* Mask flags we can ignore */
- x = ~RICHACE_POSIX_ALWAYS_ALLOWED;
- if (!S_ISDIR(*mode_p))
- x &= ~RICHACE_DELETE_CHILD;
+ if (acl->a_flags & RICHACL_MASKED) {
+ owner.allowed &= acl->a_owner_mask;
+ group.allowed &= acl->a_group_mask;
+ everyone.allowed &= acl->a_other_mask;
+ }
- mask = richacl_masks_to_mode(acl);
- if (((acl->a_group_mask ^ richacl_mode_to_mask(mask >> 3)) & x) ||
- ((acl->a_other_mask ^ richacl_mode_to_mask(mask)) & x))
+ mode = (mode & ~S_IRWXUGO) |
+ (richacl_mask_to_mode(owner.allowed) << 6) |
+ (richacl_mask_to_mode(group.allowed) << 3) |
+ richacl_mask_to_mode(everyone.allowed);
+
+ /* Mask flags we can ignore */
+ x = ~(S_ISDIR(mode) ? 0 : RICHACE_DELETE_CHILD);
+ if (((richacl_mode_to_mask(mode >> 6) ^ owner.allowed) & x) ||
+ ((richacl_mode_to_mask(mode >> 3) ^ group.allowed) & x) ||
+ ((richacl_mode_to_mask(mode) ^ everyone.allowed) & x))
return -1;
- x &= ~RICHACE_POSIX_OWNER_ALLOWED;
- if ((acl->a_owner_mask ^ richacl_mode_to_mask(mask >> 6)) & x)
+ *mode_p = mode;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(__richacl_equiv_mode);
+
+/**
+ * richacl_equiv_mode - determine if @acl is equivalent to a file mode
+ * @mode_p: the file mode
+ *
+ * The file type in @mode_p must be set when calling richacl_equiv_mode().
+ *
+ * Returns with 0 if @acl is equivalent to a file mode; in that case, the
+ * file permission bits in @mode_p are set to the mode equivalent of @acl.
+ */
+int
+richacl_equiv_mode(const struct richacl *acl, mode_t *mode_p)
+{
+ mode_t mode = *mode_p;
+
+ if (acl->a_flags & ~RICHACL_MASKED)
return -1;
- if ((ace->e_mask ^ RICHACE_POSIX_MODE_ALL) & x)
+ if (__richacl_equiv_mode(acl, &mode))
return -1;
- *mode_p = (*mode_p & ~S_IRWXUGO) | mask;
+ if (acl->a_flags & RICHACL_MASKED) {
+ mode_t mask = richacl_masks_to_mode(acl);
+ unsigned int x;
+
+ /* Mask flags we can ignore */
+ x = ~(RICHACE_POSIX_ALWAYS_ALLOWED |
+ (S_ISDIR(mode) ? 0 : RICHACE_DELETE_CHILD));
+
+ if (((acl->a_group_mask ^ richacl_mode_to_mask(mask >> 3)) & x) ||
+ ((acl->a_other_mask ^ richacl_mode_to_mask(mask)) & x))
+ return -1;
+
+ x &= ~RICHACE_POSIX_OWNER_ALLOWED;
+ if ((acl->a_owner_mask ^ richacl_mode_to_mask(mask >> 6)) & x)
+ return -1;
+
+ mode &= ~S_IRWXUGO | mask;
+ }
+
+ *mode_p = mode;
return 0;
}
EXPORT_SYMBOL_GPL(richacl_equiv_mode);
diff --git a/include/linux/richacl.h b/include/linux/richacl.h
index c6fd0a1..8a92b89 100644
--- a/include/linux/richacl.h
+++ b/include/linux/richacl.h
@@ -297,6 +297,7 @@ extern unsigned int richacl_want_to_mask(unsigned int);
extern void richacl_compute_max_masks(struct richacl *);
extern struct richacl *richacl_chmod(struct richacl *, mode_t);
extern struct richacl *richacl_inherit(const struct richacl *, int);
+extern int __richacl_equiv_mode(const struct richacl *, mode_t *);
extern int richacl_equiv_mode(const struct richacl *, mode_t *);
/* richacl_inode.c */
--
2.1.0
next prev parent reply other threads:[~2015-04-24 11:04 UTC|newest]
Thread overview: 110+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-24 11:03 [RFC v3 00/45] Richacls Andreas Gruenbacher
2015-04-24 11:03 ` [RFC v3 01/45] vfs: Minor documentation fix Andreas Gruenbacher
2015-04-24 11:03 ` [RFC v3 02/45] uapi: Remove kernel internal declaration Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 03/45] nfsd: Checking for acl support does not require fetching any acls Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 04/45] vfs: Shrink struct posix_acl Andreas Gruenbacher
2015-04-25 7:56 ` Rasmus Villemoes
2015-04-27 10:27 ` Andreas Grünbacher
2015-04-24 11:04 ` [RFC v3 05/45] vfs: Add IS_ACL() and IS_RICHACL() tests Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 06/45] vfs: Add MAY_CREATE_FILE and MAY_CREATE_DIR permission flags Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 07/45] vfs: Add MAY_DELETE_SELF and MAY_DELETE_CHILD " Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 09/45] vfs: Add permission flags for setting file attributes Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 10/45] richacl: In-memory representation and helper functions Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 11/45] richacl: Permission mapping functions Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 12/45] richacl: Compute maximum file masks from an acl Andreas Gruenbacher
2015-05-12 21:44 ` J. Bruce Fields
2015-04-24 11:04 ` [RFC v3 15/45] vfs: Cache base_acl objects in inodes Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 16/45] vfs: Cache richacl in struct inode Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 17/45] richacl: Create-time inheritance Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 18/45] richacl: Check if an acl is equivalent to a file mode Andreas Gruenbacher
2015-04-24 11:04 ` Andreas Gruenbacher [this message]
2015-05-14 19:28 ` [RFC v3 19/45] richacl: Also recognize nontrivial mode-equivalent acls J. Bruce Fields
[not found] ` <20150514192806.GG12861-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org>
2015-05-15 20:04 ` J. Bruce Fields
[not found] ` <5e9ee3b123b3d648487cd18dc906b6a2cd23085b.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-15 20:51 ` J. Bruce Fields
2015-05-27 9:24 ` Andreas Grünbacher
2015-05-27 15:06 ` J. Bruce Fields
2015-04-24 11:04 ` [RFC v3 20/45] richacl: Automatic Inheritance Andreas Gruenbacher
[not found] ` <28e2cd75064ff56bad897b6f69356f4fb15b8128.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-13 18:01 ` Frank Filz
2015-05-13 20:22 ` Andreas Grünbacher
2015-05-13 20:28 ` Jeremy Allison
2015-05-13 20:47 ` Andreas Grünbacher
2015-05-13 20:55 ` Jeremy Allison
2015-05-13 21:15 ` Andreas Grünbacher
[not found] ` <CAHpGcMLBb+s7iSv9SN1eRX-46VU_wnbGX1nXrNkuaYVp8v0jYw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-13 20:38 ` Frank Filz
2015-05-13 21:05 ` Andreas Grünbacher
2015-05-13 22:56 ` Frank Filz
2015-05-13 23:52 ` Andreas Grünbacher
2015-05-14 15:09 ` J. Bruce Fields
[not found] ` <20150514150925.GE12861-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org>
2015-05-18 20:39 ` Andreas Grünbacher
[not found] ` <CAHpGcMLK+=Sd+5xS5bsq+7FffiKQAH_t53yAMpiukeVh1JB6Mw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-18 20:43 ` J. Bruce Fields
[not found] ` <cover.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-04-24 11:04 ` [RFC v3 08/45] vfs: Make the inode passed to inode_change_ok non-const Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 13/45] richacl: Update the file masks in chmod() Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 14/45] richacl: Permission check algorithm Andreas Gruenbacher
2015-05-22 21:08 ` J. Bruce Fields
2015-05-27 11:25 ` Andreas Grünbacher
2015-05-27 15:05 ` J. Bruce Fields
2015-04-24 11:04 ` [RFC v3 21/45] richacl: xattr mapping functions Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 22/45] vfs: Add richacl permission checking Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 25/45] richacl: acl editing helper functions Andreas Gruenbacher
[not found] ` <a74bc8fdb5d8ee5bdd5defad9729d17211266079.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-15 21:33 ` J. Bruce Fields
2015-04-24 11:04 ` [RFC v3 39/45] nfs3: Return posix acl encode errors Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 23/45] ext4: Add richacl support Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 24/45] ext4: Add richacl feature flag Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 26/45] richacl: Move everyone@ aces down the acl Andreas Gruenbacher
2015-05-18 21:20 ` J. Bruce Fields
2015-04-24 11:04 ` [RFC v3 27/45] richacl: Propagate everyone@ permissions to other aces Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 28/45] richacl: Isolate the owner and group classes Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 29/45] richacl: Apply the file masks to a richacl Andreas Gruenbacher
[not found] ` <35b73e9515f2395c8595cbbf4ea7b92216e5e2a0.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-26 21:56 ` J. Bruce Fields
2015-04-24 11:04 ` [RFC v3 30/45] richacl: Create richacl from mode values Andreas Gruenbacher
[not found] ` <b435787dd651572f42984f9dec2a68cbf38bc7bf.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-28 19:24 ` J. Bruce Fields
2015-05-28 19:25 ` J. Bruce Fields
[not found] ` <20150528192553.GB31663-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org>
2015-05-28 19:58 ` Andreas Grünbacher
2015-04-24 11:04 ` [RFC v3 31/45] richacl: Create acl with masks applied in richacl_from_mode() Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 32/45] nfsd: Remove dead declarations Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 33/45] nfsd: Keep list of acls to dispose of in compoundargs Andreas Gruenbacher
[not found] ` <4f0168389120bf67cf69ce4ac7bb8ce878aa0f5d.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-28 19:52 ` J. Bruce Fields
[not found] ` <20150528195205.GC31663-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org>
2015-05-28 20:28 ` Andreas Grünbacher
2015-04-24 11:04 ` [RFC v3 34/45] nfsd: Use richacls as internal acl representation Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 35/45] nfsd: Add richacl support Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 36/45] NFSv4: Fix GETATTR bitmap verification Andreas Gruenbacher
[not found] ` <8d601ee8babe5239b7926542c713c58502b15e35.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-28 20:33 ` J. Bruce Fields
2015-05-28 21:15 ` Andreas Grünbacher
[not found] ` <20150528203332.GD31663-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org>
2015-05-28 20:50 ` Trond Myklebust
[not found] ` <CAHQdGtTe9RfxxGU+UzxnT8A1BmhtPQaOB=g6wXpvmHTu6Ho=Jg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-28 21:05 ` Andreas Grünbacher
[not found] ` <CAHpGcM+=ydzFDeTc4_1F9dYbtJ+D_mGVLKZOYkvvRjT7ZHd_xA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-28 21:40 ` Trond Myklebust
[not found] ` <CAHQdGtQKRokdRRuGmU-qD3fxOUE8cYrtb=sNcYenVT8M8XAmYA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-28 21:55 ` Trond Myklebust
[not found] ` <CAHQdGtRaq93Rk1ZNn7tqBPJVWhWwUGS7k1XzdC3etfna4kLtDg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-28 22:09 ` Andreas Grünbacher
[not found] ` <CAHpGcMLQGc4HUZEDRKAv2yaH7wwSBBO_jrMA6+=AQ6hb=WrNUg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-28 22:24 ` Trond Myklebust
2015-05-28 22:28 ` Andreas Grünbacher
2015-05-28 21:28 ` Andreas Grünbacher
2015-04-24 11:04 ` [RFC v3 37/45] nfs/sunrpc: No more encode and decode function pointer casting Andreas Gruenbacher
2015-05-28 23:11 ` Trond Myklebust
2015-05-28 23:40 ` Andreas Grünbacher
[not found] ` <CAHpGcMKn1khdNTk=MFS7vFgLCHmxX2fVTJanertXT+Zj_BnAKA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-29 0:37 ` Trond Myklebust
[not found] ` <CAHQdGtRKLnMbB6Z5w7MCnONujHH2uBnx4VUrTL1GGfWTNwurRQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-05-29 15:30 ` Andreas Grünbacher
2015-04-24 11:04 ` [RFC v3 38/45] nfs/sunrpc: Return status code from encode functions Andreas Gruenbacher
[not found] ` <9c755df47acdef7f6a1d0195af888dafb7d3e7bf.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-28 23:39 ` Trond Myklebust
2015-04-24 11:04 ` [RFC v3 40/45] nfs: Remove unused xdr page offsets in getacl/setacl arguments Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 41/45] rpc: Allow to demand-allocate pages to encode into Andreas Gruenbacher
[not found] ` <4bf77d045d2bd3494c695229cd0505b7002cc9a2.1429868795.git.agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-05-28 23:24 ` Trond Myklebust
2015-05-29 15:46 ` Andreas Grünbacher
2015-04-24 11:04 ` [RFC v3 42/45] nfs: Add richacl support Andreas Gruenbacher
2015-05-28 23:06 ` Trond Myklebust
2015-05-28 23:29 ` Andreas Grünbacher
2015-05-29 13:15 ` Trond Myklebust
2015-05-29 15:00 ` Andreas Grünbacher
2015-05-29 15:24 ` Trond Myklebust
2015-05-29 15:45 ` Andreas Grünbacher
2015-05-29 15:54 ` Trond Myklebust
2015-05-29 15:54 ` Frank Filz
2016-06-23 16:37 ` Weston Andros Adamson
2016-06-23 17:15 ` Frank Filz
2016-07-15 8:00 ` Andreas Grünbacher
2015-04-24 11:04 ` [RFC v3 43/45] uapi/nfs: Add NFSv4.1 ACL definitions Andreas Gruenbacher
2015-05-29 14:57 ` J. Bruce Fields
2015-04-24 11:04 ` [RFC v3 44/45] nfsd: Add support for the v4.1 dacl attribute Andreas Gruenbacher
2015-04-24 11:04 ` [RFC v3 45/45] nfs: " Andreas Gruenbacher
2015-05-23 15:50 ` [RFC v3 00/45] Richacls Jeremy Allison
2015-05-23 15:56 ` Andreas Grünbacher
2015-06-25 20:03 ` Stefan (metze) Metzmacher
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