diff options
| author | Weston Andros Adamson <dros@netapp.com> | 2013-01-03 16:42:29 -0500 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2013-01-03 17:06:27 -0500 |
| commit | f8d9a897d4384b77f13781ea813156568f68b83e (patch) | |
| tree | c34e5e5b5da7a6c46d1d12b7408ef5312a55e8ca | |
| parent | d1c3ed669a2d452cacfb48c2d171a1f364dae2ed (diff) | |
| download | linux-f8d9a897d4384b77f13781ea813156568f68b83e.tar.bz2 | |
NFS: Fix access to suid/sgid executables
nfs_open_permission_mask() should only check MAY_EXEC for files that
are opened with __FMODE_EXEC.
Also fix NFSv4 access-in-open path in a similar way -- openflags must be
used because fmode will not always have FMODE_EXEC set.
This patch fixes https://bugzilla.kernel.org/show_bug.cgi?id=49101
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
| -rw-r--r-- | fs/nfs/dir.c | 16 | ||||
| -rw-r--r-- | fs/nfs/nfs4proc.c | 18 |
2 files changed, 21 insertions, 13 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 32e6c53520e2..1b2d7eb93796 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -2153,12 +2153,16 @@ static int nfs_open_permission_mask(int openflags) { int mask = 0; - if ((openflags & O_ACCMODE) != O_WRONLY) - mask |= MAY_READ; - if ((openflags & O_ACCMODE) != O_RDONLY) - mask |= MAY_WRITE; - if (openflags & __FMODE_EXEC) - mask |= MAY_EXEC; + if (openflags & __FMODE_EXEC) { + /* ONLY check exec rights */ + mask = MAY_EXEC; + } else { + if ((openflags & O_ACCMODE) != O_WRONLY) + mask |= MAY_READ; + if ((openflags & O_ACCMODE) != O_RDONLY) + mask |= MAY_WRITE; + } + return mask; } diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 5d864fb36578..cf747ef86650 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -1626,7 +1626,8 @@ static int _nfs4_recover_proc_open(struct nfs4_opendata *data) static int nfs4_opendata_access(struct rpc_cred *cred, struct nfs4_opendata *opendata, - struct nfs4_state *state, fmode_t fmode) + struct nfs4_state *state, fmode_t fmode, + int openflags) { struct nfs_access_entry cache; u32 mask; @@ -1638,11 +1639,14 @@ static int nfs4_opendata_access(struct rpc_cred *cred, mask = 0; /* don't check MAY_WRITE - a newly created file may not have - * write mode bits, but POSIX allows the creating process to write */ - if (fmode & FMODE_READ) - mask |= MAY_READ; - if (fmode & FMODE_EXEC) - mask |= MAY_EXEC; + * write mode bits, but POSIX allows the creating process to write. + * use openflags to check for exec, because fmode won't + * always have FMODE_EXEC set when file open for exec. */ + if (openflags & __FMODE_EXEC) { + /* ONLY check for exec rights */ + mask = MAY_EXEC; + } else if (fmode & FMODE_READ) + mask = MAY_READ; cache.cred = cred; cache.jiffies = jiffies; @@ -1896,7 +1900,7 @@ static int _nfs4_do_open(struct inode *dir, if (server->caps & NFS_CAP_POSIX_LOCK) set_bit(NFS_STATE_POSIX_LOCKS, &state->flags); - status = nfs4_opendata_access(cred, opendata, state, fmode); + status = nfs4_opendata_access(cred, opendata, state, fmode, flags); if (status != 0) goto err_opendata_put; |