| Message ID | 20230817202210.never.014-kees@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Paul Moore |
| Headers | show |
| Series | selinux: Annotate struct sidtab_str_cache with __counted_by | expand |
On 8/17/23 14:22, Kees Cook wrote: > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct sidtab_str_cache. > > [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci > > Cc: Paul Moore <paul@paul-moore.com> > Cc: Stephen Smalley <stephen.smalley.work@gmail.com> > Cc: Eric Paris <eparis@parisplace.org> > Cc: Ondrej Mosnacek <omosnace@redhat.com> > Cc: selinux@vger.kernel.org > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks -- Gustavo > --- > security/selinux/ss/sidtab.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c > index d8ead463b8df..732fd8e22a12 100644 > --- a/security/selinux/ss/sidtab.c > +++ b/security/selinux/ss/sidtab.c > @@ -25,7 +25,7 @@ struct sidtab_str_cache { > struct list_head lru_member; > struct sidtab_entry *parent; > u32 len; > - char str[]; > + char str[] __counted_by(len); > }; > > #define index_to_sid(index) ((index) + SECINITSID_NUM + 1)
On Thu, Aug 17, 2023 at 4:22 PM Kees Cook <keescook@chromium.org> wrote: > > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct sidtab_str_cache. > > [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci > > Cc: Paul Moore <paul@paul-moore.com> > Cc: Stephen Smalley <stephen.smalley.work@gmail.com> > Cc: Eric Paris <eparis@parisplace.org> > Cc: Ondrej Mosnacek <omosnace@redhat.com> > Cc: selinux@vger.kernel.org > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > security/selinux/ss/sidtab.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) This also looks good to me, but similarly to the audit patch, since we are at -rc6 I'm going to wait to merge this until after the merge window. I'll send a follow up email once it's merged. Thanks. > diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c > index d8ead463b8df..732fd8e22a12 100644 > --- a/security/selinux/ss/sidtab.c > +++ b/security/selinux/ss/sidtab.c > @@ -25,7 +25,7 @@ struct sidtab_str_cache { > struct list_head lru_member; > struct sidtab_entry *parent; > u32 len; > - char str[]; > + char str[] __counted_by(len); > }; > > #define index_to_sid(index) ((index) + SECINITSID_NUM + 1) > -- > 2.34.1
On Fri, Aug 18, 2023 at 12:25:12PM -0400, Paul Moore wrote: > On Thu, Aug 17, 2023 at 4:22 PM Kees Cook <keescook@chromium.org> wrote: > > > > Prepare for the coming implementation by GCC and Clang of the __counted_by > > attribute. Flexible array members annotated with __counted_by can have > > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > > functions). > > > > As found with Coccinelle[1], add __counted_by for struct sidtab_str_cache. > > > > [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci > > > > Cc: Paul Moore <paul@paul-moore.com> > > Cc: Stephen Smalley <stephen.smalley.work@gmail.com> > > Cc: Eric Paris <eparis@parisplace.org> > > Cc: Ondrej Mosnacek <omosnace@redhat.com> > > Cc: selinux@vger.kernel.org > > Signed-off-by: Kees Cook <keescook@chromium.org> > > --- > > security/selinux/ss/sidtab.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > This also looks good to me, but similarly to the audit patch, since we > are at -rc6 I'm going to wait to merge this until after the merge > window. I'll send a follow up email once it's merged. Thanks! Yeah, there's no rush. :)
On Aug 17, 2023 Kees Cook <keescook@chromium.org> wrote: > > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct sidtab_str_cache. > > [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci > > Cc: Paul Moore <paul@paul-moore.com> > Cc: Stephen Smalley <stephen.smalley.work@gmail.com> > Cc: Eric Paris <eparis@parisplace.org> > Cc: Ondrej Mosnacek <omosnace@redhat.com> > Cc: selinux@vger.kernel.org > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > security/selinux/ss/sidtab.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Merged into selinux/next, thanks. -- paul-moore.com
diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c index d8ead463b8df..732fd8e22a12 100644 --- a/security/selinux/ss/sidtab.c +++ b/security/selinux/ss/sidtab.c @@ -25,7 +25,7 @@ struct sidtab_str_cache { struct list_head lru_member; struct sidtab_entry *parent; u32 len; - char str[]; + char str[] __counted_by(len); }; #define index_to_sid(index) ((index) + SECINITSID_NUM + 1)
Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct sidtab_str_cache. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Paul Moore <paul@paul-moore.com> Cc: Stephen Smalley <stephen.smalley.work@gmail.com> Cc: Eric Paris <eparis@parisplace.org> Cc: Ondrej Mosnacek <omosnace@redhat.com> Cc: selinux@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> --- security/selinux/ss/sidtab.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)