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author | Sabrina Dubroca <sd@queasysnail.net> | 2024-02-28 23:44:00 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-03-06 14:48:37 +0000 |
commit | 81be85353b0f5a7b660635634b655329b429eefe (patch) | |
tree | f9f2542afdbd26816174be09ce2e1fd0995d8d89 /net/tls | |
parent | dec5b6e7b211e405d3bcb504562ab21aa7e5a64d (diff) | |
download | linux-stable-81be85353b0f5a7b660635634b655329b429eefe.tar.gz linux-stable-81be85353b0f5a7b660635634b655329b429eefe.tar.bz2 linux-stable-81be85353b0f5a7b660635634b655329b429eefe.zip |
tls: fix use-after-free on failed backlog decryption
[ Upstream commit 13114dc5543069f7b97991e3b79937b6da05f5b0 ]
When the decrypt request goes to the backlog and crypto_aead_decrypt
returns -EBUSY, tls_do_decryption will wait until all async
decryptions have completed. If one of them fails, tls_do_decryption
will return -EBADMSG and tls_decrypt_sg jumps to the error path,
releasing all the pages. But the pages have been passed to the async
callback, and have already been released by tls_decrypt_done.
The only true async case is when crypto_aead_decrypt returns
-EINPROGRESS. With -EBUSY, we already waited so we can tell
tls_sw_recvmsg that the data is available for immediate copy, but we
need to notify tls_decrypt_sg (via the new ->async_done flag) that the
memory has already been released.
Fixes: 859054147318 ("net: tls: handle backlogging of crypto requests")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/r/4755dd8d9bebdefaa19ce1439b833d6199d4364c.1709132643.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/tls')
-rw-r--r-- | net/tls/tls_sw.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 733dbae9b057..acf5bb74fd38 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -52,6 +52,7 @@ struct tls_decrypt_arg { struct_group(inargs, bool zc; bool async; + bool async_done; u8 tail; ); @@ -286,15 +287,18 @@ static int tls_do_decryption(struct sock *sk, } ret = crypto_aead_decrypt(aead_req); + if (ret == -EINPROGRESS) + return 0; + if (ret == -EBUSY) { ret = tls_decrypt_async_wait(ctx); - ret = ret ?: -EINPROGRESS; - } - if (ret == -EINPROGRESS) { - return 0; - } else if (darg->async) { - atomic_dec(&ctx->decrypt_pending); + darg->async_done = true; + /* all completions have run, we're not doing async anymore */ + darg->async = false; + return ret; } + + atomic_dec(&ctx->decrypt_pending); darg->async = false; return ret; @@ -1593,8 +1597,11 @@ static int tls_decrypt_sg(struct sock *sk, struct iov_iter *out_iov, /* Prepare and submit AEAD request */ err = tls_do_decryption(sk, sgin, sgout, dctx->iv, data_len + prot->tail_size, aead_req, darg); - if (err) + if (err) { + if (darg->async_done) + goto exit_free_skb; goto exit_free_pages; + } darg->skb = clear_skb ?: tls_strp_msg(ctx); clear_skb = NULL; @@ -1606,6 +1613,9 @@ static int tls_decrypt_sg(struct sock *sk, struct iov_iter *out_iov, return err; } + if (unlikely(darg->async_done)) + return 0; + if (prot->tail_size) darg->tail = dctx->tail; |