We need to error out when trying to add an entry above SIDTAB_MAX in sidtab_reverse_lookup() to avoid overflow on the odd chance that this happens. Fixes: ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve performance") Signed-off-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx> --- security/selinux/ss/sidtab.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c index e63a90ff2728..1f0a6eaa2d6a 100644 --- a/security/selinux/ss/sidtab.c +++ b/security/selinux/ss/sidtab.c @@ -286,6 +286,11 @@ static int sidtab_reverse_lookup(struct sidtab *s, struct context *context, ++count; } + /* bail out if we already reached max entries */ + rc = -EOVERFLOW; + if (count >= SIDTAB_MAX) + goto out_unlock; + /* insert context into new entry */ rc = -ENOMEM; dst = sidtab_do_lookup(s, count, 1); -- 2.21.0