[ Upstream commit 5112ed5258b8d5e0769ae7d2bf9c9dea14c59703 ]

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: 0b6a6b72b329 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>

commit 4d587cd8a72155089a627130bbd4716ec0856e21 upstream.

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: cf60af03ca4e ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

aa_dfa_unpack returns ERR_PTR not NULL when it fails, but aa_put_dfa
only checks NULL for its input, which would cause invalid memory access
in aa_put_dfa. Set nulldfa to NULL explicitly to fix that.

Fixes: 98b824ff8984 ("apparmor: refcount the pdb")
Signed-off-by: GONG Ruiqi <gongruiqi1@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

In apparmor_path_rename(), when handling RENAME_EXCHANGE, the
cond_exchange structure is supposed to carry the attributes of the
*new* dentry (since it is used to authorize moving new_dentry to the
old location). However, line 412 reads:

    vfsuid = i_uid_into_vfsuid(idmap, d_backing_inode(old_dentry));

This fetches the uid of old_dentry instead of new_dentry. As a result,
the RENAME_EXCHANGE permission check uses the wrong file owner, which
can allow a rename that should be denied (if old_dentry's owner has
more privileges) or deny one that should be allowed.

Note that cond_exchange.mode on the line above correctly uses
new_dentry. Only the uid lookup is wrong.

Fix by changing old_dentry to new_dentry in the i_uid_into_vfsuid call.

Fixes: 5e26a01e56fd ("apparmor: use type safe idmapping helpers")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: Dudu Lu <phx0fer@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

Replace sprintf() with sysfs_emit() in param_get_audit() and
param_get_mode(). sysfs_emit() is preferred for formatting sysfs output
because it provides safer bounds checking.  Add terminating newlines as
suggested by checkpatch.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: John Johansen <john.johansen@canonical.com>

Remove the redundant if check in sk_peer_get_label() and return
ERR_PTR(-ENOPROTOOPT) directly.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: John Johansen <john.johansen@canonical.com>

Use kmemdup_nul() to copy 'value' instead of using memcpy() followed by
a manual NUL termination.  No functional changes.

Reviewed-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor_getprocattr() incorrectly calls task_ctx(current) instead of
task_ctx(task) when retrieving prev and exec attributes, returning the
caller's labels rather than the target's.

Fix by passing task to task_ctx().

The issue can be reproduced when a process with an onexec transition
(e.g., configured by a container runtime) is inspected via
/proc/<pid>/attr/apparmor/exec. The reader's own value is returned
instead of the target's.

Reported-by: Qualys Security Advisory <qsa@qualys.com>
Fixes: 3b529a7600d8 ("apparmor: move task domain change info to task security")
Cc: stable@vger.kernel.org
Co-developed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: Cengiz Can <cengiz.can@canonical.com>
Co-developed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>