kernel/linux.git/include/linux/key.h, branch v6.19.11

KEYS: Invert FINAL_PUT bit

2025-06-11T18:57:14+00:00

Invert the FINAL_PUT bit so that test_bit_acquire and clear_bit_unlock can be used instead of smp_mb. Signed-off-by: Herbert Xu Signed-off-by: David Howells Reviewed-by: Jarkko Sakkinen Signed-off-by: Linus Torvalds

keys: Fix UAF in key_put()

2025-03-22T13:36:49+00:00

Once a key's reference count has been reduced to 0, the garbage collector thread may destroy it at any time and so key_put() is not allowed to touch the key after that point. The most key_put() is normally allowed to do is to touch key_gc_work as that's a static global variable. However, in an effort to speed up the reclamation of quota, this is now done in key_put() once the key's usage is reduced to 0 - but now the code is looking at the key after the deadline, which is forbidden. Fix this by using a flag to indicate that a key can be gc'd now rather than looking at the key's refcount in the garbage collector. Fixes: 9578e327b2b4 ("keys: update key quotas in key_put()") Reported-by: syzbot+6105ffc1ded71d194d6d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/673b6aec.050a0220.87769.004a.GAE@google.com/ Signed-off-by: David Howells Tested-by: syzbot+6105ffc1ded71d194d6d@syzkaller.appspotmail.com Reviewed-by: Oleg Nesterov Signed-off-by: Jarkko Sakkinen

KEYS: Remove unused declarations

2024-09-20T15:28:26+00:00

These declarations are never implemented, remove it. Signed-off-by: Yue Haibing Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen

security/keys: export key_lookup()

2023-10-11T17:11:54+00:00

For in-kernel consumers one cannot readily assign a user (eg when running from a workqueue), so the normal key search permissions cannot be applied. This patch exports the 'key_lookup()' function for a simple lookup of keys without checking for permissions. Signed-off-by: Hannes Reinecke Reviewed-by: Sagi Grimberg Acked-by: David Howells Signed-off-by: Keith Busch

sysctl: move security keys sysctl registration to its own file

2023-06-08T22:42:02+00:00

The security keys sysctls are already declared on its own file, just move the sysctl registration to its own file to help avoid merge conflicts on sysctls.c, and help with clearing up sysctl.c further. This creates a small penalty of 23 bytes: ./scripts/bloat-o-meter vmlinux.1 vmlinux.2 add/remove: 2/0 grow/shrink: 0/1 up/down: 49/-26 (23) Function old new delta init_security_keys_sysctls - 33 +33 __pfx_init_security_keys_sysctls - 16 +16 sysctl_init_bases 85 59 -26 Total: Before=21256937, After=21256960, chg +0.00% But soon we'll be saving tons of bytes anyway, as we modify the sysctl registrations to use ARRAY_SIZE and so we get rid of all the empty array elements so let's just clean this up now. Reviewed-by: Paul Moore Acked-by: Jarkko Sakkinen Acked-by: David Howells Signed-off-by: Luis Chamberlain

KEYS: Add new function key_create()

2023-02-13T08:11:20+00:00

key_create() works like key_create_or_update() but does not allow updating an existing key, instead returning ERR_PTR(-EEXIST). key_create() will be used by the blacklist keyring which should not create duplicate entries or update existing entries. Instead a dedicated message with appropriate severity will be logged. Signed-off-by: Thomas Weißschuh Signed-off-by: Jarkko Sakkinen

KEYS: Move KEY_LOOKUP_ to include/linux/key.h and define KEY_LOOKUP_ALL

2022-09-22T00:32:48+00:00

In preparation for the patch that introduces the bpf_lookup_user_key() eBPF kfunc, move KEY_LOOKUP_ definitions to include/linux/key.h, to be able to validate the kfunc parameters. Add them to enum key_lookup_flag, so that all the current ones and the ones defined in the future are automatically exported through BTF and available to eBPF programs. Also, add KEY_LOOKUP_ALL to the enum, with the logical OR of currently defined flags as value, to facilitate checking whether a variable contains only those flags. Signed-off-by: Roberto Sassu Acked-by: Jarkko Sakkinen Link: https://lore.kernel.org/r/20220920075951.929132-7-roberto.sassu@huaweicloud.com Signed-off-by: Alexei Starovoitov

certs: Fix blacklist flag type confusion

2021-01-21T16:16:10+00:00

KEY_FLAG_KEEP is not meant to be passed to keyring_alloc() or key_alloc(), as these only take KEY_ALLOC_* flags. KEY_FLAG_KEEP has the same value as KEY_ALLOC_BYPASS_RESTRICTION, but fortunately only key_create_or_update() uses it. LSMs using the key_alloc hook don't check that flag. KEY_FLAG_KEEP is then ignored but fortunately (again) the root user cannot write to the blacklist keyring, so it is not possible to remove a key/hash from it. Fix this by adding a KEY_ALLOC_SET_KEEP flag that tells key_alloc() to set KEY_FLAG_KEEP on the new key. blacklist_init() can then, correctly, pass this to keyring_alloc(). We can also use this in ima_mok_init() rather than setting the flag manually. Note that this doesn't fix an observable bug with the current implementation but it is required to allow addition of new hashes to the blacklist in the future without making it possible for them to be removed. Fixes: 734114f8782f ("KEYS: Add a system blacklist keyring") Reported-by: Mickaël Salaün Signed-off-by: David Howells cc: Mickaël Salaün cc: Mimi Zohar Cc: David Woodhouse

keys: remove trailing semicolon in macro definition

2021-01-21T16:16:10+00:00

The macro use will already have a semicolon. Signed-off-by: Tom Rix Signed-off-by: David Howells Acked-by: Jarkko Sakkinen Reviewed-by: Ben Boeckel

keys: Make the KEY_NEED_* perms an enum rather than a mask

2020-05-19T14:42:22+00:00

Since the meaning of combining the KEY_NEED_* constants is undefined, make it so that you can't do that by turning them into an enum. The enum is also given some extra values to represent special circumstances, such as: (1) The '0' value is reserved and causes a warning to trap the parameter being unset. (2) The key is to be unlinked and we require no permissions on it, only the keyring, (this replaces the KEY_LOOKUP_FOR_UNLINK flag). (3) An override due to CAP_SYS_ADMIN. (4) An override due to an instantiation token being present. (5) The permissions check is being deferred to later key_permission() calls. The extra values give the opportunity for LSMs to audit these situations. [Note: This really needs overhauling so that lookup_user_key() tells key_task_permission() and the LSM what operation is being done and leaves it to those functions to decide how to map that onto the available permits. However, I don't really want to make these change in the middle of the notifications patchset.] Signed-off-by: David Howells cc: Jarkko Sakkinen cc: Paul Moore cc: Stephen Smalley cc: Casey Schaufler cc: keyrings@vger.kernel.org cc: selinux@vger.kernel.org