The fix for tcp-fast-open ensures that the connect permission is being
mediated correctly but it didn't add an artifact to the feature set to
advertise the fix is available. Add an artifact so that the test suite
can identify if the fix has not been properly applied or a new
unexpected regression has occurred.
Fixes: 4d587cd8a7 ("apparmor: mediate the implicit connect of TCP fast open sendmsg")
Signed-off-by: John Johansen <john.johansen@canonical.com>
sendmsg()/sendto() with MSG_FASTOPEN is a combination of connect(2) and
write(2): it opens the connection in the SYN. apparmor_socket_sendmsg()
only checks AA_MAY_SEND, so a profile that grants send but denies connect
lets a confined task open an outbound TCP/MPTCP connection that connect(2)
would have refused, bypassing connect mediation.
Mediate the implicit connect when MSG_FASTOPEN is set and a destination
is supplied. Add it to apparmor_socket_sendmsg() (not the shared
aa_sock_msg_perm() helper, which recvmsg also uses) and call aa_sk_perm()
directly, mirroring the selinux and tomoyo fixes. sk_is_tcp() does not
cover MPTCP fast open, so the SOCK_STREAM/IPPROTO_MPTCP arm is explicit.
Fixes: cf60af03ca ("net-tcp: Fast Open client - sendmsg(MSG_FASTOPEN)")
Cc: stable@vger.kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Fix error reported by kernel test robot
security/apparmor/policy.c:1381:2: error: a label can only be part of
a statement and a declaration is not a statement
All errors (new ones prefixed by >>):
security/apparmor/policy.c: In function 'aa_replace_profiles':
>> security/apparmor/policy.c:1381:2: error: a label can only be part
of a statement and a declaration is not a statement
ssize_t udata_sz = udata->size;
^~~~~
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202606150525.npax8WiH-lkp@intel.com/
Fixes: 7b42f95813 ("apparmor: fix potential UAF in aa_replace_profiles")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Fix two kernel-doc warnings:
- non-kernel-doc comment marked with '/**' in af_unix.c
- documented symbol name mismatch for aa_get_i_loaddata() in
policy_unpack.h
No functional changes.
Signed-off-by: Rodrigo Zaiden <rodrigoffzz@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
multi_transaction_new() allocates memory with get_zeroed_page() and uses
it as struct multi_transaction.
The usage of that structure does not require struct page access and it is
better to allocate multi_transaction objects with kzalloc() that provides
better scalability and more debugging possibilities.
Replace use of get_zeroed_page() with kzalloc().
Link: https://lore.kernel.org/all/635405e4-9423-4a25-a6e7-e03c8ea0bcbe@redhat.com
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
aa_replace_profiles() walks ns->rawdata_list to dedup the incoming
policy blob against entries already attached to existing profiles.
Per the kernel-doc on struct aa_loaddata, list membership does not
hold a reference: profiles hold pcount, and when the last pcount
drops, do_ploaddata_rmfs() is queued on a workqueue that takes
ns->lock and removes the entry. Between dropping the last pcount
and the workqueue running, an entry remains on the list with
pcount == 0.
aa_get_profile_loaddata() is an unconditional kref_get() on
pcount, so when the dedup loop hits such an entry, refcount
hardening reports
refcount_t: addition on 0; use-after-free.
inside aa_replace_profiles(), and the poisoned counter then
trips "saturated" and "underflow" warnings on the subsequent
uses of the same loaddata.
Before commit a0b7091c4d ("apparmor: fix race on rawdata
dereference") the dedup path used a get_unless_zero-style helper
on a single counter, so the existing "if (tmp)" guard was
meaningful. The split-refcount refactor introduced
aa_get_profile_loaddata(), which has plain kref_get() semantics,
and the guard quietly became a no-op.
Introduce aa_get_profile_loaddata_not0(), matching the existing
_not0 convention used by aa_get_profile_not0(), and use it for
the rawdata_list dedup lookup so dying entries are skipped.
Reproduced on x86_64 with v7.1-rc5 in QEMU+KVM running Ubuntu
24.04 + stress-ng 0.17.06:
stress-ng --apparmor 1 --klog-check --timeout 60s
Without this patch the three refcount_t warnings fire within a
few seconds. With it the same 60 s run is clean. Coverage is a
smoke-test only; a longer soak with CONFIG_KASAN, CONFIG_KCSAN
and CONFIG_PROVE_LOCKING would be welcome from anyone with the
cycles.
Fixes: a0b7091c4d ("apparmor: fix race on rawdata dereference")
Reported-by: Colin Ian King <colin.i.king@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221513
Cc: stable@vger.kernel.org
Signed-off-by: Ruslan Valiyev <linuxoid@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
cache_hold_inc() prevents the per-CPU cache hold counter from
rising above MAX_HOLD_COUNT, but the comparison is inverted
(> MAX_HOLD_COUNT instead of <), so the counter never rises
above 0.
This breaks the cache mechanism because since the hold counter
is always 0, the global pool is always attempted first before
falling back to the local cache. The decrement also never occurs,
thus the hold counter is effectively dead.
Fix by changing > to < in cache_hold_inc().
Fixes: 0b6a6b72b3 ("apparmor: document the buffer hold, add an overflow guard")
Signed-off-by: Eduardo Vasconcelos <eduardo@eduardovasconcelos.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
In
commit 4a134723f9 ("apparmor: move check for aa_null file to cover all cases")
there was a change to not audit files pointing to
aa_null.dentry because they provide no value, but setting the error
variable instead of returning -EACCES was still causing them to be
audited.
Fixes: 4a134723f9 ("apparmor: move check for aa_null file to cover all cases")
Acked-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
apparmor_secmark_init() parses a configured secmark label to obtain its
secid. aa_label_strn_parse() returns a refcounted label, but the success
path kept that reference after copying the secid.
Fixes: ab9f211508 ("apparmor: Allow filtering based on secmark policy")
Signed-off-by: Zygmunt Krynicki <me@zygoon.pl>
Signed-off-by: John Johansen <john.johansen@canonical.com>
aa_getprocattr() allocates the output string before rendering the label
into it. If the second aa_label_snxprint() call fails, the function
returned without freeing that allocation.
Free and clear the output pointer on the uncommon formatting failure path
before dropping the namespace reference.
Fixes: 76a1d263ab ("apparmor: switch getprocattr to using label_print fns()")
Reviewed-by: Tyler Hicks <code@thicks.com>
Reviewed-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: Zygmunt Krynicki <me@zygoon.pl>
Signed-off-by: John Johansen <john.johansen@canonical.com>
There is no need for a goto a label immediately following the
conditional block when the jump is the last statement in the block.
Fixes: 7306c41672 ("apparmor: release exe file resources on path failure")
Signed-off-by: John Johansen <john.johansen@canonical.com>
get_current_exe_path() takes both an exe_file reference and a path
reference before resolving the path name. If aa_path_name() failed, it
returned immediately and leaked both references.
Route the failure through the common cleanup path so fput() and path_put()
always run after the references are acquired.
Fixes: 8d34e16f7f ("apparmor: userns: Add support for execpath in userns")
Reviewed-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: Zygmunt Krynicki <me@zygoon.pl>
Signed-off-by: John Johansen <john.johansen@canonical.com>
unpack_pdb() may need to allocate a missing ACCEPT2 table for older policy
data. If that allocation failed, it set an error message but jumped to the
success path, returning a policydb with the required table missing.
Return -ENOMEM through the normal failure path when the ACCEPT2 allocation
fails. Remove the now-unused out label.
Fixes: 2e12c5f060 ("apparmor: add additional flags to extended permission.")
Reviewed-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: Zygmunt Krynicki <me@zygoon.pl>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Return NULL instead of passing to ERR_PTR while error is zero.
Fixes smatch warning:
- security/apparmor/apparmorfs.c:1846 ns_mkdir_op() warn:
passing zero to 'ERR_PTR'
Fixes: 88d5baf690 ("Change inode_operations.mkdir to return struct dentry *")
Reviewed-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: Hongling Zeng <zenghongling@kylinos.cn>
Signed-off-by: John Johansen <john.johansen@canonical.com>
When the export_binary parameter is set, then rawdata is available and
there should be a symbolic link for the rawdata in the profile
directory in apparmorfs. If the parameter is unset, then the symlinks
should not exist.
The issue arises when changing the value of export_binary on runtime
and replacing profiles. If export_binary was set when the profile was
originally loaded, then changed to 0 and the profile was reloaded,
then the symbolic links would still exist but would return ENOENT
because the rawdata no longer exists.
On the opposite side, if export_binary was unset when the profile was
originally loaded, then changed to 1 and the profile was reloaded,
then the symbolic links would not exist, even though the rawdata does.
Fixes: d61c57fde8 ("apparmor: make export of raw binary profile to userspace optional")
Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Currently fn_label_build() callback fns must provide a transition or
failure. Change this so that a callback can indicate it should be
skipped/not be involved in the label being built.
This will be useful when building object labels based on mediation
flags, as to whether the label should be set.
Existing callers can keep treating NULL return as an error because
none of those callback fns support skipping, but instead of the old
error handling replace with AA_BUG.
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Previously fn_label_build() was accepting a NULL which represented
ENOMEM return and ERR_PTR for errors.
Clean this up by requiring the cb fn to return an ERR_PTR or valid
value.
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The function aa_replace_profiles was accessing udata->size after calling
aa_put_loaddata(udata), causing a potential UAF.
Fixed this by saving the size to a local variable before dropping the
reference.
Fixes: 5ac8c355ae ("apparmor: allow introspecting the loaded policy pre internal transform")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: Maxime Bélair <maxime.belair@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
profiles can be pinned by file and other references, and can live long
after they have been replaced/removed. The rawdata however is no longer
needed, and can be freed earlier than the rest of the profile.
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
There was a race condition involving change_hat and profile replacement in
which replacement of the parent profile during a changehat operation could
result in the list of children becoming empty and the changehat operation
failing. To prevent this:
- grab the namespace lock until we've built the hat transition, and
- use aa_get_newest_profile to avoid using stale profile objects.
Link: https://bugs.launchpad.net/bugs/2139664
Fixes: 89dbf1962a ("apparmor: move change_hat mediation to using labels")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
rawdata_f_data has a blob of data that is allocated at its end but
not explicitly declared. Makes sure it is correctly declared as a
flex_rray.
Fixes: 63c16c3a76 ("apparmor: Initial implementation of raw policy blob compression")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>