diff options
| author | Jann Horn <jannh@google.com> | 2019-05-28 17:32:26 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-25 11:36:51 +0800 |
| commit | 4758984fa3ba0b1ac39687750e74ca0350ada753 (patch) | |
| tree | aa508999ef986b14bc06de846ca5a0018932fddd /security | |
| parent | fadee027bf8fa90f3057a98a89871cbe8dd4adf5 (diff) | |
apparmor: enforce nullbyte at end of tag string
commit 8404d7a674c49278607d19726e0acc0cae299357 upstream.
A packed AppArmor policy contains null-terminated tag strings that are read
by unpack_nameX(). However, unpack_nameX() uses string functions on them
without ensuring that they are actually null-terminated, potentially
leading to out-of-bounds accesses.
Make sure that the tag string is null-terminated before passing it to
strcmp().
Cc: stable@vger.kernel.org
Fixes: 736ec752d95e ("AppArmor: policy routines for loading and unpacking policy")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'security')
| -rw-r--r-- | security/apparmor/policy_unpack.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index 4ede87c30f8b..2cef8d4404cc 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -259,7 +259,7 @@ static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name) char *tag = NULL; size_t size = unpack_u16_chunk(e, &tag); /* if a name is specified it must match. otherwise skip tag */ - if (name && (!size || strcmp(name, tag))) + if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag))) goto fail; } else if (name) { /* if a name is specified and there is no name tag fail */ |