diff options
| author | Herbert Xu <herbert@gondor.apana.org.au> | 2019-12-06 13:55:17 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-14 16:32:12 -0500 |
| commit | 4fa9dd9ce20ffd2f327cddcacd19c3e44603df54 (patch) | |
| tree | 3075b1ecd3ede9a2ec60484c40680e52dcf5c388 /crypto | |
| parent | 0fb0ea3cb8cc45298ed0be3f3732b7ea6143aecc (diff) | |
crypto: api - Check spawn->alg under lock in crypto_drop_spawn
commit 7db3b61b6bba4310f454588c2ca6faf2958ad79f upstream.
We need to check whether spawn->alg is NULL under lock as otherwise
the algorithm could be removed from under us after we have checked
it and found it to be non-NULL. This could cause us to remove the
spawn from a non-existent list.
Fixes: 7ede5a5ba55a ("crypto: api - Fix crypto_drop_spawn crash...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/algapi.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/crypto/algapi.c b/crypto/algapi.c index 50eb828db767..0e86cab3bb67 100644 --- a/crypto/algapi.c +++ b/crypto/algapi.c @@ -652,11 +652,9 @@ EXPORT_SYMBOL_GPL(crypto_grab_spawn); void crypto_drop_spawn(struct crypto_spawn *spawn) { - if (!spawn->alg) - return; - down_write(&crypto_alg_sem); - list_del(&spawn->list); + if (spawn->alg) + list_del(&spawn->list); up_write(&crypto_alg_sem); } EXPORT_SYMBOL_GPL(crypto_drop_spawn); |