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| author | Yang Xu <xuyang2018.jy@cn.fujitsu.com> | 2020-02-28 12:41:51 +0800 |
|---|---|---|
| committer | Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> | 2020-03-15 20:59:50 +0200 |
| commit | 2e356101e72ab1361821b3af024d64877d9a798d (patch) | |
| tree | acb6e134ca1b89783de19a23a6786bc262a7686a /security/keys | |
| parent | 18b3670d79ae9948a5839f0956a47e4eb4130a63 (diff) | |
| download | linux-2e356101e72ab1361821b3af024d64877d9a798d.tar.gz linux-2e356101e72ab1361821b3af024d64877d9a798d.tar.bz2 linux-2e356101e72ab1361821b3af024d64877d9a798d.zip | |
KEYS: reaching the keys quotas correctly
Currently, when we add a new user key, the calltrace as below:
add_key()
key_create_or_update()
key_alloc()
__key_instantiate_and_link
generic_key_instantiate
key_payload_reserve
......
Since commit a08bf91ce28e ("KEYS: allow reaching the keys quotas exactly"),
we can reach max bytes/keys in key_alloc, but we forget to remove this
limit when we reserver space for payload in key_payload_reserve. So we
can only reach max keys but not max bytes when having delta between plen
and type->def_datalen. Remove this limit when instantiating the key, so we
can keep consistent with key_alloc.
Also, fix the similar problem in keyctl_chown_key().
Fixes: 0b77f5bfb45c ("keys: make the keyring quotas controllable through /proc/sys")
Fixes: a08bf91ce28e ("KEYS: allow reaching the keys quotas exactly")
Cc: stable@vger.kernel.org # 5.0.x
Cc: Eric Biggers <ebiggers@google.com>
Signed-off-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Diffstat (limited to 'security/keys')
| -rw-r--r-- | security/keys/key.c | 2 | ||||
| -rw-r--r-- | security/keys/keyctl.c | 4 |
2 files changed, 3 insertions, 3 deletions
diff --git a/security/keys/key.c b/security/keys/key.c index 718bf7217420..e959b3c96b48 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -382,7 +382,7 @@ int key_payload_reserve(struct key *key, size_t datalen) spin_lock(&key->user->lock); if (delta > 0 && - (key->user->qnbytes + delta >= maxbytes || + (key->user->qnbytes + delta > maxbytes || key->user->qnbytes + delta < key->user->qnbytes)) { ret = -EDQUOT; } diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 9b898c969558..d1a3dea58dee 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -937,8 +937,8 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group) key_quota_root_maxbytes : key_quota_maxbytes; spin_lock(&newowner->lock); - if (newowner->qnkeys + 1 >= maxkeys || - newowner->qnbytes + key->quotalen >= maxbytes || + if (newowner->qnkeys + 1 > maxkeys || + newowner->qnbytes + key->quotalen > maxbytes || newowner->qnbytes + key->quotalen < newowner->qnbytes) goto quota_overrun; |