From: "Christopher J. Morrone" <morrone2@xxxxxxxx> We have found that posix_acl_access can have a value of \002\000\000\000. In that case body->aclsize is non-zero, but the there are no actuall acls stored in the xattr. In mdc_unpack_acl(), it only checks IS_ERR() on the pointer returned by posix_acl_from_xattr(), it does not check for NULL. Because of the above situation, the xattr aclsize can be non-zero, but posic_acl_from_xattr() still returns NULL. Passing NULL to posix_acl_valid() crashes the kernel. We add a check to properly handle the NULL return value. Signed-off-by: Christopher J. Morrone <morrone2@xxxxxxxx> Reviewed-on: http://review.whamcloud.com/11989 Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5150 Reviewed-by: Fan Yong <fan.yong@xxxxxxxxx> Reviewed-by: Bob Glossman <bob.glossman@xxxxxxxxx> Signed-off-by: Oleg Drokin <oleg.drokin@xxxxxxxxx> --- drivers/staging/lustre/lustre/mdc/mdc_request.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/staging/lustre/lustre/mdc/mdc_request.c b/drivers/staging/lustre/lustre/mdc/mdc_request.c index c04eec5..f8ef5fe 100644 --- a/drivers/staging/lustre/lustre/mdc/mdc_request.c +++ b/drivers/staging/lustre/lustre/mdc/mdc_request.c @@ -481,6 +481,9 @@ static int mdc_unpack_acl(struct ptlrpc_request *req, struct lustre_md *md) return -EPROTO; acl = posix_acl_from_xattr(&init_user_ns, buf, body->aclsize); + if (acl == NULL) + return 0; + if (IS_ERR(acl)) { rc = PTR_ERR(acl); CERROR("convert xattr to acl: %d\n", rc); -- 2.1.0 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
