Re: [PATCH 4/4] AppArmor: export known rlimit names/value mappingsin securityfs

From: John Johansen
Date: Fri Jan 27 2012 - 14:35:14 EST


On 01/26/2012 04:29 PM, Kees Cook wrote:
> Since the parser needs to know which rlimits are known to the kernel,
> export the list via a mask file in the "rlimit" subdirectory in the
> securityfs "features" directory.
>
> Signed-off-by: Kees Cook <kees@xxxxxxxxxx>
Acked-by: John Johansen <john.johansen@xxxxxxxxxxxxx>


> ---
> security/apparmor/Makefile | 24 ++++++++++++++++++------
> security/apparmor/apparmorfs.c | 2 ++
> security/apparmor/include/resource.h | 4 ++++
> security/apparmor/resource.c | 5 +++++
> 4 files changed, 29 insertions(+), 6 deletions(-)
>
> diff --git a/security/apparmor/Makefile b/security/apparmor/Makefile
> index 2dafe50..86103ce 100644
> --- a/security/apparmor/Makefile
> +++ b/security/apparmor/Makefile
> @@ -28,25 +28,37 @@ cmd_make-caps = echo "static const char *capability_names[] = {" > $@ ;\
> # [RLIMIT_STACK] = "stack",
> #
> # and build a second integer table (with the second sed cmd), that maps
> -# RLIMIT defines to the order defined in asm-generic/resource.h Thi is
> +# RLIMIT defines to the order defined in asm-generic/resource.h This is
> # required by policy load to map policy ordering of RLIMITs to internal
> # ordering for architectures that redefine an RLIMIT.
> # Transforms lines from
> # #define RLIMIT_STACK 3 /* max stack size */
> # to
> # RLIMIT_STACK,
> +#
> +# and build the securityfs entries for the mapping.
> +# Transforms lines from
> +# #define RLIMIT_FSIZE 1 /* Maximum filesize */
> +# #define RLIMIT_STACK 3 /* max stack size */
> +# to
> +# #define AA_FS_RLIMIT_MASK "fsize stack"
> quiet_cmd_make-rlim = GEN $@
> -cmd_make-rlim = echo "static const char *rlim_names[] = {" > $@ ;\
> +cmd_make-rlim = echo "static const char *rlim_names[RLIM_NLIMITS] = {" > $@ ;\
> sed $< >> $@ -r -n \
> -e 's/^\# ?define[ \t]+(RLIMIT_([A-Z0-9_]+)).*/[\1] = "\L\2",/p';\
> echo "};" >> $@ ;\
> - echo "static const int rlim_map[] = {" >> $@ ;\
> + echo "static const int rlim_map[RLIM_NLIMITS] = {" >> $@ ;\
> sed -r -n "s/^\# ?define[ \t]+(RLIMIT_[A-Z0-9_]+).*/\1,/p" $< >> $@ ;\
> - echo "};" >> $@
> + echo "};" >> $@ ; \
> + echo -n '\#define AA_FS_RLIMIT_MASK "' >> $@ ;\
> + sed -r -n 's/^\# ?define[ \t]+RLIMIT_([A-Z0-9_]+).*/\L\1/p' $< | \
> + tr '\n' ' ' | sed -e 's/ $$/"\n/' >> $@
>
> $(obj)/capability.o : $(obj)/capability_names.h
> $(obj)/resource.o : $(obj)/rlim_names.h
> -$(obj)/capability_names.h : $(srctree)/include/linux/capability.h
> +$(obj)/capability_names.h : $(srctree)/include/linux/capability.h \
> + $(src)/Makefile
> $(call cmd,make-caps)
> -$(obj)/rlim_names.h : $(srctree)/include/asm-generic/resource.h
> +$(obj)/rlim_names.h : $(srctree)/include/asm-generic/resource.h \
> + $(src)/Makefile
> $(call cmd,make-rlim)
> diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
> index 68ce771..38d6262 100644
> --- a/security/apparmor/apparmorfs.c
> +++ b/security/apparmor/apparmorfs.c
> @@ -25,6 +25,7 @@
> #include "include/audit.h"
> #include "include/context.h"
> #include "include/policy.h"
> +#include "include/resource.h"
>
> /**
> * aa_simple_write_to_buffer - common routine for getting policy from user
> @@ -202,6 +203,7 @@ static struct aa_fs_entry aa_fs_entry_features[] = {
> AA_FS_DIR("file", aa_fs_entry_file),
> AA_FS_FILE_BOOLEAN("namespaces", 1),
> AA_FS_FILE_U64("capability", VFS_CAP_FLAGS_MASK),
> + AA_FS_DIR("rlimit", aa_fs_entry_rlimit),
> { }
> };
>
> diff --git a/security/apparmor/include/resource.h b/security/apparmor/include/resource.h
> index 02baec7..d3f4cf0 100644
> --- a/security/apparmor/include/resource.h
> +++ b/security/apparmor/include/resource.h
> @@ -18,6 +18,8 @@
> #include <linux/resource.h>
> #include <linux/sched.h>
>
> +#include "apparmorfs.h"
> +
> struct aa_profile;
>
> /* struct aa_rlimit - rlimit settings for the profile
> @@ -32,6 +34,8 @@ struct aa_rlimit {
> struct rlimit limits[RLIM_NLIMITS];
> };
>
> +extern struct aa_fs_entry aa_fs_entry_rlimit[];
> +
> int aa_map_resource(int resource);
> int aa_task_setrlimit(struct aa_profile *profile, struct task_struct *,
> unsigned int resource, struct rlimit *new_rlim);
> diff --git a/security/apparmor/resource.c b/security/apparmor/resource.c
> index a4136c1..72c25a4 100644
> --- a/security/apparmor/resource.c
> +++ b/security/apparmor/resource.c
> @@ -23,6 +23,11 @@
> */
> #include "rlim_names.h"
>
> +struct aa_fs_entry aa_fs_entry_rlimit[] = {
> + AA_FS_FILE_STRING("mask", AA_FS_RLIMIT_MASK),
> + { }
> +};
> +
> /* audit callback for resource specific fields */
> static void audit_cb(struct audit_buffer *ab, void *va)
> {

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/