diff options
| author | Ari Kauppi <ari@synopsys.com> | 2017-05-05 16:07:55 -0400 |
|---|---|---|
| committer | J. Bruce Fields <bfields@redhat.com> | 2017-05-09 17:09:18 -0400 |
| commit | b550a32e60a4941994b437a8d662432a486235a5 (patch) | |
| tree | ee8f276ffae29999291a7338cb4e3df02619863a | |
| parent | efda760fe95ea15291853c8fa9235c32d319cd98 (diff) | |
nfsd: fix undefined behavior in nfsd4_layout_verify
UBSAN: Undefined behaviour in fs/nfsd/nfs4proc.c:1262:34
shift exponent 128 is too large for 32-bit type 'int'
Depending on compiler+architecture, this may cause the check for
layout_type to succeed for overly large values (which seems to be the
case with amd64). The large value will be later used in de-referencing
nfsd4_layout_ops for function pointers.
Reported-by: Jani Tuovila <tuovila@synopsys.com>
Signed-off-by: Ari Kauppi <ari@synopsys.com>
[colin.king@canonical.com: use LAYOUT_TYPE_MAX instead of 32]
Cc: stable@vger.kernel.org
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
| -rw-r--r-- | fs/nfsd/nfs4proc.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index d86031b6ad79..c453a1998e00 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1259,7 +1259,8 @@ nfsd4_layout_verify(struct svc_export *exp, unsigned int layout_type) return NULL; } - if (!(exp->ex_layout_types & (1 << layout_type))) { + if (layout_type >= LAYOUT_TYPE_MAX || + !(exp->ex_layout_types & (1 << layout_type))) { dprintk("%s: layout type %d not supported\n", __func__, layout_type); return NULL; |