linux-stable.git/security/keys, branch linux-5.10.y

keys: Pin request_key_auth payload in instantiate paths

2026-07-04T11:38:40+00:00

commit fd15b457a86939c38aa12116adabd8ff686c5e51 upstream.

A: request_key()       B: KEYCTL_INSTANTIATE_IOV
================       =========================

create auth key
store rka in auth key
wait for helper
                       get auth key
                       load rka from auth key
                       copy user payload
                       sleep on #PF

helper completed
detach and free rka
destroy auth key
                       wake up
                       use rka->target_key
                       **USE-AFTER-FREE**

Give request_key_auth payloads a refcount.  Take a payload reference while
authkey->sem stabilizes the payload and revocation state.  Hold that
reference across the instantiate and reject paths.  Drop the auth key
owning reference from revoke and destroy.

[jarkko: Replaced the first two paragraphs of text with an actual
 concurrency scenario.]
Cc: stable@vger.kernel.org # v5.10+
Fixes: b5f545c880a2 ("[PATCH] keys: Permit running process to instantiate keys")
Reported-by: Shaomin Chen 
Closes: https://lore.kernel.org/r/20260519144403.436694-1-eeesssooo020@gmail.com
Signed-off-by: Shaomin Chen 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Greg Kroah-Hartman

KEYS: fix overflow in keyctl_pkey_params_get_2()

2026-07-04T11:38:40+00:00

commit cb481e59ea6cae3b7796ac1d7a22b6b24c3f3c0b upstream.

The length for the internal output buffer is calculated incorrectly, which
can result overflow when a too small buffer is provided.

Fix the bug by allocating internal output with the size of the maximum
length of the cryptographic primitive instead of caller provided size.

Link: https://lore.kernel.org/keyrings/20260531024914.3712130-1-jarkko@kernel.org/
Cc: stable@vger.kernel.org # v4.20+
Fixes: 00d60fd3b932 ("KEYS: Provide keyctls to drive the new key type ops for asymmetric keys [ver #2]")
Reported-by: Alessandro Groppo 
Tested-by: Alessandro Groppo 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Greg Kroah-Hartman

use less confusing names for iov_iter direction initializers

2026-06-19T11:21:45+00:00

[ Upstream commit de4eda9de2d957ef2d6a8365a01e26a435e958cb ]

READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.

Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...

Signed-off-by: Al Viro 
Stable-dep-of: a4f0b001782b ("vsock/virtio: reset connection on receiving queue overflow")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

KEYS: trusted_tpm1: Compare HMAC values in constant time

2025-10-29T13:01:24+00:00

[ Upstream commit eed0e3d305530066b4fc5370107cff8ef1a0d229 ]

To prevent timing attacks, HMAC value comparison needs to be constant
time.  Replace the memcmp() with the correct function, crypto_memneq().

[For the Fixes commit I used the commit that introduced the memcmp().
It predates the introduction of crypto_memneq(), but it was still a bug
at the time even though a helper function didn't exist yet.]

Fixes: d00a1c72f7f4 ("keys: add new trusted key-type")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers 
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen 
[ replaced crypto/utils.h include with crypto/algapi.h ]
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

security/keys: fix slab-out-of-bounds in key_task_permission

2024-11-17T13:59:35+00:00

[ Upstream commit 4a74da044ec9ec8679e6beccc4306b936b62873f ]

KASAN reports an out of bounds read:
BUG: KASAN: slab-out-of-bounds in __kuid_val include/linux/uidgid.h:36
BUG: KASAN: slab-out-of-bounds in uid_eq include/linux/uidgid.h:63 [inline]
BUG: KASAN: slab-out-of-bounds in key_task_permission+0x394/0x410
security/keys/permission.c:54
Read of size 4 at addr ffff88813c3ab618 by task stress-ng/4362

CPU: 2 PID: 4362 Comm: stress-ng Not tainted 5.10.0-14930-gafbffd6c3ede #15
Call Trace:
 __dump_stack lib/dump_stack.c:82 [inline]
 dump_stack+0x107/0x167 lib/dump_stack.c:123
 print_address_description.constprop.0+0x19/0x170 mm/kasan/report.c:400
 __kasan_report.cold+0x6c/0x84 mm/kasan/report.c:560
 kasan_report+0x3a/0x50 mm/kasan/report.c:585
 __kuid_val include/linux/uidgid.h:36 [inline]
 uid_eq include/linux/uidgid.h:63 [inline]
 key_task_permission+0x394/0x410 security/keys/permission.c:54
 search_nested_keyrings+0x90e/0xe90 security/keys/keyring.c:793

This issue was also reported by syzbot.

It can be reproduced by following these steps(more details [1]):
1. Obtain more than 32 inputs that have similar hashes, which ends with the
   pattern '0xxxxxxxe6'.
2. Reboot and add the keys obtained in step 1.

The reproducer demonstrates how this issue happened:
1. In the search_nested_keyrings function, when it iterates through the
   slots in a node(below tag ascend_to_node), if the slot pointer is meta
   and node->back_pointer != NULL(it means a root), it will proceed to
   descend_to_node. However, there is an exception. If node is the root,
   and one of the slots points to a shortcut, it will be treated as a
   keyring.
2. Whether the ptr is keyring decided by keyring_ptr_is_keyring function.
   However, KEYRING_PTR_SUBTYPE is 0x2UL, the same as
   ASSOC_ARRAY_PTR_SUBTYPE_MASK.
3. When 32 keys with the similar hashes are added to the tree, the ROOT
   has keys with hashes that are not similar (e.g. slot 0) and it splits
   NODE A without using a shortcut. When NODE A is filled with keys that
   all hashes are xxe6, the keys are similar, NODE A will split with a
   shortcut. Finally, it forms the tree as shown below, where slot 6 points
   to a shortcut.

                      NODE A
              +------>+---+
      ROOT    |       | 0 | xxe6
      +---+   |       +---+
 xxxx | 0 | shortcut  :   : xxe6
      +---+   |       +---+
 xxe6 :   :   |       |   | xxe6
      +---+   |       +---+
      | 6 |---+       :   : xxe6
      +---+           +---+
 xxe6 :   :           | f | xxe6
      +---+           +---+
 xxe6 | f |
      +---+

4. As mentioned above, If a slot(slot 6) of the root points to a shortcut,
   it may be mistakenly transferred to a key*, leading to a read
   out-of-bounds read.

To fix this issue, one should jump to descend_to_node if the ptr is a
shortcut, regardless of whether the node is root or not.

[1] https://lore.kernel.org/linux-kernel/1cfa878e-8c7b-4570-8606-21daf5e13ce7@huaweicloud.com/

[jarkko: tweaked the commit message a bit to have an appropriate closes
 tag.]
Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
Reported-by: syzbot+5b415c07907a2990d1a3@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000cbb7860611f61147@google.com/T/
Signed-off-by: Chen Ridong 
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Sasha Levin

task_work: s/task_work_cancel()/task_work_cancel_func()/

2024-08-19T03:40:57+00:00

commit 68cbd415dd4b9c5b9df69f0f091879e56bf5907a upstream.

A proper task_work_cancel() API that actually cancels a callback and not
*any* callback pointing to a given function is going to be needed for
perf events event freeing. Do the appropriate rename to prepare for
that.

Signed-off-by: Frederic Weisbecker 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240621091601.18227-2-frederic@kernel.org
Signed-off-by: Greg Kroah-Hartman

keys: Fix overwrite of key expiration on instantiation

2024-05-17T09:48:11+00:00

commit 9da27fb65a14c18efd4473e2e82b76b53ba60252 upstream.

The expiry time of a key is unconditionally overwritten during
instantiation, defaulting to turn it permanent. This causes a problem
for DNS resolution as the expiration set by user-space is overwritten to
TIME64_MAX, disabling further DNS updates. Fix this by restoring the
condition that key_set_expiry is only called when the pre-parser sets a
specific expiry.

Fixes: 39299bdd2546 ("keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry")
Signed-off-by: Silvio Gissi 
cc: David Howells 
cc: Hazem Mohamed Abuelfotoh 
cc: linux-afs@lists.infradead.org
cc: linux-cifs@vger.kernel.org
cc: keyrings@vger.kernel.org
cc: netdev@vger.kernel.org
cc: stable@vger.kernel.org
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Greg Kroah-Hartman

keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry

2024-01-05T14:12:25+00:00

[ Upstream commit 39299bdd2546688d92ed9db4948f6219ca1b9542 ]

If a key has an expiration time, then when that time passes, the key is
left around for a certain amount of time before being collected (5 mins by
default) so that EKEYEXPIRED can be returned instead of ENOKEY.  This is a
problem for DNS keys because we want to redo the DNS lookup immediately at
that point.

Fix this by allowing key types to be marked such that keys of that type
don't have this extra period, but are reclaimed as soon as they expire and
turn this on for dns_resolver-type keys.  To make this easier to handle,
key->expiry is changed to be permanent if TIME64_MAX rather than 0.

Furthermore, give such new-style negative DNS results a 1s default expiry
if no other expiry time is set rather than allowing it to stick around
indefinitely.  This shouldn't be zero as ls will follow a failing stat call
immediately with a second with AT_SYMLINK_NOFOLLOW added.

Fixes: 1a4240f4764a ("DNS: Separate out CIFS DNS Resolver code")
Signed-off-by: David Howells 
Tested-by: Markus Suvanto 
cc: Wang Lei 
cc: Jeff Layton 
cc: Steve French 
cc: Marc Dionne 
cc: Jarkko Sakkinen 
cc: "David S. Miller" 
cc: Eric Dumazet 
cc: Jakub Kicinski 
cc: Paolo Abeni 
cc: linux-afs@lists.infradead.org
cc: linux-cifs@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: keyrings@vger.kernel.org
cc: netdev@vger.kernel.org
Signed-off-by: Sasha Levin

security: keys: perform capable check only on privileged operations

2023-09-19T10:20:05+00:00

[ Upstream commit 2d7f105edbb3b2be5ffa4d833abbf9b6965e9ce7 ]

If the current task fails the check for the queried capability via
`capable(CAP_SYS_ADMIN)` LSMs like SELinux generate a denial message.
Issuing such denial messages unnecessarily can lead to a policy author
granting more privileges to a subject than needed to silence them.

Reorder CAP_SYS_ADMIN checks after the check whether the operation is
actually privileged.

Signed-off-by: Christian Göttsche 
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Sasha Levin

security: keys: Modify mismatched function name

2023-07-27T06:44:39+00:00

[ Upstream commit 2a4152742025c5f21482e8cebc581702a0fa5b01 ]

No functional modification involved.

security/keys/trusted-keys/trusted_tpm2.c:203: warning: expecting prototype for tpm_buf_append_auth(). Prototype was for tpm2_buf_append_auth() instead.

Fixes: 2e19e10131a0 ("KEYS: trusted: Move TPM2 trusted keys code")
Reported-by: Abaci Robot 
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=5524
Signed-off-by: Jiapeng Chong 
Reviewed-by: Paul Moore 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Sasha Levin