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author | Rick Macklem <rmacklem@FreeBSD.org> | 2021-12-01 21:55:17 +0000 |
---|---|---|
committer | Rick Macklem <rmacklem@FreeBSD.org> | 2021-12-15 01:38:56 +0000 |
commit | b5c577931db12c68f5a20fa11c9502049c3cdb40 (patch) | |
tree | e236181986a3755be07475e0877108598da4901e | |
parent | a85d71e4c788b8e149de151a6b262a996c7bc311 (diff) | |
download | src-b5c577931db12c68f5a20fa11c9502049c3cdb40.tar.gz src-b5c577931db12c68f5a20fa11c9502049c3cdb40.zip |
nfsd: Sanity check the ACL attribute
When an ACL is presented to the NFSv4 server in
Setattr or Verify, parsing of the ACL assumed a
sane acecnt and sane sizes for the "who" strings.
This patch adds sanity checks for these.
The patch also fixes handling of an error
return from nfsrv_dissectacl() for one broken
case.
PR: 260111
(cherry picked from commit fd020f197d6ac481d36171ea69fe555eb911d673)
-rw-r--r-- | sys/fs/nfs/nfs_commonacl.c | 6 | ||||
-rw-r--r-- | sys/fs/nfs/nfs_commonsubs.c | 10 |
2 files changed, 15 insertions, 1 deletions
diff --git a/sys/fs/nfs/nfs_commonacl.c b/sys/fs/nfs/nfs_commonacl.c index 7fb744417d6a..6254a6b6568c 100644 --- a/sys/fs/nfs/nfs_commonacl.c +++ b/sys/fs/nfs/nfs_commonacl.c @@ -58,7 +58,11 @@ nfsrv_dissectace(struct nfsrv_descript *nd, struct acl_entry *acep, flag = fxdr_unsigned(u_int32_t, *tl++); mask = fxdr_unsigned(u_int32_t, *tl++); len = fxdr_unsigned(int, *tl); - if (len < 0) { + /* + * The RFCs do not specify a limit to the length of the "who", but + * NFSV4_OPAQUELIMIT (1024) should be sufficient. + */ + if (len < 0 || len > NFSV4_OPAQUELIMIT) { error = NFSERR_BADXDR; goto nfsmout; } else if (len == 0) { diff --git a/sys/fs/nfs/nfs_commonsubs.c b/sys/fs/nfs/nfs_commonsubs.c index e4120d4d9e78..dcdf2e96c7e8 100644 --- a/sys/fs/nfs/nfs_commonsubs.c +++ b/sys/fs/nfs/nfs_commonsubs.c @@ -1085,6 +1085,14 @@ nfsrv_dissectacl(struct nfsrv_descript *nd, NFSACL_T *aclp, int *aclerrp, NFSM_DISSECT(tl, u_int32_t *, NFSX_UNSIGNED); aclsize = NFSX_UNSIGNED; acecnt = fxdr_unsigned(int, *tl); + /* + * The RFCs do not define a fixed limit to the number of ACEs in + * an ACL, but 10240 should be more than sufficient. + */ + if (acecnt < 0 || acecnt > 10240) { + error = NFSERR_BADXDR; + goto nfsmout; + } if (acecnt > ACL_MAX_ENTRIES) aceerr = NFSERR_ATTRNOTSUPP; if (nfsrv_useacl == 0) @@ -1468,6 +1476,8 @@ nfsv4_loadattr(struct nfsrv_descript *nd, vnode_t vp, } else { error = nfsrv_dissectacl(nd, NULL, &aceerr, &cnt, p); + if (error) + goto nfsmout; *retcmpp = NFSERR_ATTRNOTSUPP; } } |