[PATCH 4/4] xfs_repair: Validate richacl attributes

[Dave Chinner]

On Fri, Oct 23, 2015 at 09:17:08PM +0200, Andreas Gruenbacher wrote:
> When we have the <sys/richacl.h> header and a working copy of librichacl.a (the
> static version of the richacl library), use that to validate richacl attribute
> values.
> 
> Signed-off-by: Andreas Gruenbacher <agruenba at redhat.com>
> ---
>  configure.ac         | 22 ++++++++++++++++++++++
>  include/builddefs.in |  5 +++++
>  repair/Makefile      |  2 +-
>  repair/attr_repair.c | 41 ++++++++++++++++++++++++++++++++++++++++-
>  4 files changed, 68 insertions(+), 2 deletions(-)
> 
> diff --git a/configure.ac b/configure.ac
> index 7b57521..2584ea2 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -101,6 +101,28 @@ AC_PACKAGE_GLOBALS(xfsprogs)
>  AC_PACKAGE_UTILITIES(xfsprogs)
>  AC_MULTILIB($enable_lib64)
>  
> +have_richacl=no
> +librichacl=
> +AC_CHECK_HEADERS([sys/richacl.h])
> +if test "$ac_cv_header_sys_richacl_h" = yes; then
> +    AC_CHECK_HEADERS([linux/xattr.h])
> +    saved_LIBS=$LIBS
> +    librichacl=-l:librichacl.a
> +    LIBS="$LIBS $librichacl"
> +    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([
> +	#include <sys/richacl.h>
> +    ],[
> +	int valid = richacl_valid((struct richacl *)0);
> +    ])], [
> +	have_richacl=yes
> +    ], [
> +	librichacl=
> +    ])
> +    LIBS=$saved_LIBS
> +fi
> +AC_SUBST([have_richacl])
> +AC_SUBST([librichacl])
> +
>  AC_PACKAGE_NEED_AIO_H
>  AC_PACKAGE_NEED_LIO_LISTIO
>  
> diff --git a/include/builddefs.in b/include/builddefs.in
> index c1797fd..b64e027 100644
> --- a/include/builddefs.in
> +++ b/include/builddefs.in
> @@ -34,6 +34,7 @@ LIBTERMCAP = @libtermcap@
>  LIBEDITLINE = @libeditline@
>  LIBREADLINE = @libreadline@
>  LIBBLKID = @libblkid@
> +LIBRICHACL = @librichacl@
>  LIBXFS = $(TOPDIR)/libxfs/libxfs.la
>  LIBXCMD = $(TOPDIR)/libxcmd/libxcmd.la
>  LIBXLOG = $(TOPDIR)/libxlog/libxlog.la
> @@ -108,6 +109,7 @@ HAVE_MNTENT = @have_mntent@
>  HAVE_FLS = @have_fls@
>  HAVE_FSETXATTR = @have_fsetxattr@
>  HAVE_MREMAP = @have_mremap@
> +HAVE_RICHACL = @have_richacl@
>  
>  GCCFLAGS = -funsigned-char -fno-strict-aliasing -Wall 
>  #	   -Wbitwise -Wno-transparent-union -Wno-old-initializer -Wno-decl
> @@ -147,6 +149,9 @@ endif
>  ifeq ($(ENABLE_BLKID),yes)
>  PCFLAGS+= -DENABLE_BLKID
>  endif
> +ifeq ($(HAVE_RICHACL),yes)
> +PCFLAGS += -DHAVE_RICHACL
> +endif
>  
>  
>  GCFLAGS = $(OPTIMIZER) $(DEBUG) \
> diff --git a/repair/Makefile b/repair/Makefile
> index 251722b..032f453 100644
> --- a/repair/Makefile
> +++ b/repair/Makefile
> @@ -20,7 +20,7 @@ CFILES = agheader.c attr_repair.c avl.c avl64.c bmap.c btree.c \
>  	progress.c prefetch.c rt.c sb.c scan.c threads.c \
>  	versions.c xfs_repair.c
>  
> -LLDLIBS = $(LIBXFS) $(LIBXLOG) $(LIBUUID) $(LIBRT) $(LIBPTHREAD)
> +LLDLIBS = $(LIBXFS) $(LIBXLOG) $(LIBUUID) $(LIBRT) $(LIBPTHREAD) $(LIBRICHACL)
>  LTDEPENDENCIES = $(LIBXFS) $(LIBXLOG)
>  LLDFLAGS = -static-libtool-libs
>  
> diff --git a/repair/attr_repair.c b/repair/attr_repair.c
> index e03f360..e7f03a8 100644
> --- a/repair/attr_repair.c
> +++ b/repair/attr_repair.c
> @@ -26,6 +26,17 @@
>  #include "dir2.h"
>  #include "da_util.h"
>  
> +#ifdef HAVE_RICHACL
> +# if HAVE_LINUX_XATTR_H
> +#  include <linux/xattr.h>
> +# endif
> +# ifndef XATTR_RICHACL
> +#  define XATTR_RICHACL "richacl"
> +# endif
> +
> +# include <sys/richacl.h>
> +#endif
> +
>  static int xfs_acl_valid(struct xfs_mount *mp, struct xfs_acl *daclp);
>  static int xfs_mac_valid(xfs_mac_label_t *lp);
>  
> @@ -195,6 +206,35 @@ valuecheck(
>  		if ( valuelen != sizeof(xfs_cap_set_t))
>  			clearit = 1;
>  	}
> +#if HAVE_RICHACL
> +	else if (namelen == strlen(XATTR_RICHACL) &&
> +		 strncmp(namevalue, XATTR_RICHACL, strlen(XATTR_RICHACL)) == 0) {
> +		struct richacl *acl;
> +
> +		if (value == NULL) {
> +			valuep = malloc(valuelen);
> +			if (!valuep)
> +				do_error(_("No memory for ACL check!\n"));
> +			memcpy(valuep, namevalue + namelen, valuelen);
> +		} else
> +			valuep = value;
> +
> +		acl = richacl_from_xattr(valuep, valuelen);
> +		if (!acl) {
> +			if (errno == ENOMEM)
> +				do_error(_("No memory for ACL check!\n"));
> +			else
> +				clearit = 1;
> +		} else {
> +			if (richacl_valid(acl) != 0)
> +				clearit = 1;
> +			richacl_free(acl);
> +		}
> +
> +		if (valuep != value)
> +			free(valuep);
> +	}
> +#endif

This also needs to check that the richacl feature bit is set
apprpriately for the type of ACL that is found. i.e. if we find a
posix ACL on a richacl enabled filesystem (or vice versa), that's
indicative of a kernel bug and we need to take action on it..

Cheers,

Dave.
-- 
Dave Chinner
david at fromorbit.com