linux-kernel - [PATCH 002 of 9] knfsd: nfsd4: relax checking of ACL inheritance bits

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 13 Feb 2007 10:44:07 +1100
From:	NeilBrown <neilb@...e.de>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	nfs@...ts.sourceforge.net, linux-kernel@...r.kernel.org
Subject: [PATCH 002 of 9] knfsd: nfsd4: relax checking of ACL inheritance bits


From: J. Bruce Fields <bfields@...i.umich.edu>
The rfc allows us to be more permissive about the ACL inheritance bits we
accept:

	"If the server supports a single "inherit ACE" flag that applies to
	both files and directories, the server may reject the request
	(i.e., requiring the client to set both the file and directory
	inheritance flags). The server may also accept the request and
	silently turn on the ACE4_DIRECTORY_INHERIT_ACE flag."

Let's take the latter option--the ACL is a complex attribute that could be
rejected for a wide variety of reasons, and the protocol gives us little
ability to explain the reason for the rejection, so erroring out is a
user-unfriendly last resort.

Signed-off-by: J. Bruce Fields <bfields@...i.umich.edu>
Signed-off-by: Neil Brown <neilb@...e.de>

### Diffstat output
 ./fs/nfsd/nfs4acl.c |   23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff .prev/fs/nfsd/nfs4acl.c ./fs/nfsd/nfs4acl.c
--- .prev/fs/nfsd/nfs4acl.c	2007-02-13 09:50:26.000000000 +1100
+++ ./fs/nfsd/nfs4acl.c	2007-02-13 10:01:42.000000000 +1100
@@ -61,9 +61,11 @@
 
 /* flags used to simulate posix default ACLs */
 #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \
-		| NFS4_ACE_DIRECTORY_INHERIT_ACE | NFS4_ACE_INHERIT_ONLY_ACE)
+		| NFS4_ACE_DIRECTORY_INHERIT_ACE)
 
-#define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS | NFS4_ACE_IDENTIFIER_GROUP)
+#define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \
+		| NFS4_ACE_INHERIT_ONLY_ACE \
+		| NFS4_ACE_IDENTIFIER_GROUP)
 
 #define MASK_EQUAL(mask1, mask2) \
 	( ((mask1) & NFS4_ACE_MASK_ALL) == ((mask2) & NFS4_ACE_MASK_ALL) )
@@ -707,11 +709,16 @@ nfs4_acl_split(struct nfs4_acl *acl, str
 		if (ace->flag & ~NFS4_SUPPORTED_FLAGS)
 			return -EINVAL;
 
-		switch (ace->flag & NFS4_INHERITANCE_FLAGS) {
-		case 0:
+		if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) {
 			/* Leave this ace in the effective acl: */
 			continue;
-		case NFS4_INHERITANCE_FLAGS:
+		}
+		/*
+		 * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT
+		 * is set, we're effectively turning on the other.  That's OK,
+		 * according to rfc 3530.
+		 */
+		if (ace->flag & NFS4_ACE_INHERIT_ONLY_ACE) {
 			/* Add this ace to the default acl and remove it
 			 * from the effective acl: */
 			error = nfs4_acl_add_ace(dacl, ace->type, ace->flag,
@@ -721,17 +728,13 @@ nfs4_acl_split(struct nfs4_acl *acl, str
 			list_del(h);
 			kfree(ace);
 			acl->naces--;
-			break;
-		case NFS4_INHERITANCE_FLAGS & ~NFS4_ACE_INHERIT_ONLY_ACE:
+		} else {
 			/* Add this ace to the default, but leave it in
 			 * the effective acl as well: */
 			error = nfs4_acl_add_ace(dacl, ace->type, ace->flag,
 				ace->access_mask, ace->whotype, ace->who);
 			if (error)
 				return error;
-			break;
-		default:
-			return -EINVAL;
 		}
 	}
 	return 0;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/