linux.git/crypto/algif_hash.c, branch v6.8

crypto: algif_hash - Remove bogus SGL free on zero-length error path

2024-02-02T10:08:12+00:00

When a zero-length message is hashed by algif_hash, and an error
is triggered, it tries to free an SG list that was never allocated
in the first place.  Fix this by not freeing the SG list on the
zero-length error path.

Reported-by: Shigeru Yoshida 
Reported-by: xingwei lee 
Fixes: b6d972f68983 ("crypto: af_alg/hash: Fix recvmsg() after sendmsg(MSG_MORE)")
Cc: 
Signed-off-by: Herbert Xu 
Reported-by: syzbot+3266db0c26d1fbbe3abb@syzkaller.appspotmail.com
Signed-off-by: Herbert Xu

crypto: algif_hash - Fix race between MORE and non-MORE sends

2023-07-08T12:48:42+00:00

The 'MSG_MORE' state of the previous sendmsg() is fetched without the
socket lock held, so two sendmsg calls can race.  This can be seen with a
large sendfile() as that now does a series of sendmsg() calls, and if a
write() comes in on the same socket at an inopportune time, it can flip the
state.

Fix this by moving the fetch of ctx->more inside the socket lock.

Fixes: c662b043cdca ("crypto: af_alg/hash: Support MSG_SPLICE_PAGES")
Reported-by: syzbot+689ec3afb1ef07b766b2@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/000000000000554b8205ffdea64e@google.com/
Signed-off-by: David Howells 
Tested-by: syzbot+689ec3afb1ef07b766b2@syzkaller.appspotmail.com
cc: Herbert Xu 
cc: Paolo Abeni 
cc: "David S. Miller" 
cc: Eric Dumazet 
cc: Jakub Kicinski 
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
Signed-off-by: Herbert Xu

crypto: af_alg/hash: Fix recvmsg() after sendmsg(MSG_MORE)

2023-06-20T19:10:36+00:00

If an AF_ALG socket bound to a hashing algorithm is sent a zero-length
message with MSG_MORE set and then recvmsg() is called without first
sending another message without MSG_MORE set to end the operation, an oops
will occur because the crypto context and result doesn't now get set up in
advance because hash_sendmsg() now defers that as long as possible in the
hope that it can use crypto_ahash_digest() - and then because the message
is zero-length, it the data wrangling loop is skipped.

Fix this by handling zero-length sends at the top of the hash_sendmsg()
function.  If we're not continuing the previous sendmsg(), then just ignore
the send (hash_recvmsg() will invent something when called); if we are
continuing, then we finalise the request at this point if MSG_MORE is not
set to get any error here, otherwise the send is of no effect and can be
ignored.

Whilst we're at it, remove the code to create a kvmalloc'd scatterlist if
we get more than ALG_MAX_PAGES - this shouldn't happen.

Fixes: c662b043cdca ("crypto: af_alg/hash: Support MSG_SPLICE_PAGES")
Reported-by: syzbot+13a08c0bf4d212766c3c@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/000000000000b928f705fdeb873a@google.com/
Reported-by: syzbot+14234ccf6d0ef629ec1a@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/000000000000c047db05fdeb8790@google.com/
Reported-by: syzbot+4e2e47f32607d0f72d43@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/000000000000bcca3205fdeb87fb@google.com/
Reported-by: syzbot+472626bb5e7c59fb768f@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/000000000000b55d8805fdeb8385@google.com/
Signed-off-by: David Howells 
Reported-and-tested-by: syzbot+6efc50cc1f8d718d6cb7@syzkaller.appspotmail.com
cc: Jens Axboe 
cc: Matthew Wilcox 
Acked-by: Herbert Xu 
Link: https://lore.kernel.org/r/427646.1686913832@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski

algif: Remove hash_sendpage*()

2023-06-13T04:13:23+00:00

Remove hash_sendpage*() as nothing should now call it since the rewrite of
splice_to_socket()[1].

Signed-off-by: David Howells 
cc: Herbert Xu 
cc: Jens Axboe 
cc: Matthew Wilcox 
Link: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=2dc334f1a63a8839b88483a3e73c0f27c9c1791c [1]
Signed-off-by: Jakub Kicinski

crypto: af_alg/hash: Support MSG_SPLICE_PAGES

2023-06-08T11:42:34+00:00

Make AF_ALG sendmsg() support MSG_SPLICE_PAGES in the hashing code.  This
causes pages to be spliced from the source iterator if possible.

This allows ->sendpage() to be replaced by something that can handle
multiple multipage folios in a single transaction.

Signed-off-by: David Howells 
cc: Herbert Xu 
cc: "David S. Miller" 
cc: Eric Dumazet 
cc: Jakub Kicinski 
cc: Paolo Abeni 
cc: Jens Axboe 
cc: Matthew Wilcox 
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
Acked-by: Herbert Xu 
Signed-off-by: Paolo Abeni

crypto: af_alg: Use extract_iter_to_sg() to create scatterlists

2023-06-08T11:42:34+00:00

Use extract_iter_to_sg() to decant the destination iterator into a
scatterlist in af_alg_get_rsgl().  af_alg_make_sg() can then be removed.

Signed-off-by: David Howells 
cc: Herbert Xu 
cc: "David S. Miller" 
cc: Eric Dumazet 
cc: Jakub Kicinski 
cc: Paolo Abeni 
cc: Jens Axboe 
cc: Matthew Wilcox 
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
Acked-by: Herbert Xu 
Signed-off-by: Paolo Abeni

crypto: algif_hash - Allocate hash state with kmalloc

2023-04-06T08:18:53+00:00

Allocating the hash state on the stack limits its size.  Change
this to use kmalloc so the limit can be removed for new drivers.

Signed-off-by: Herbert Xu

af_alg_make_sg(): switch to advancing variant of iov_iter_get_pages()

2022-08-09T02:37:23+00:00

... and adjust the callers

Reviewed-by: Jeff Layton 
Signed-off-by: Al Viro

net: make ->{get,set}sockopt in proto_ops optional

2020-07-20T01:16:41+00:00

Just check for a NULL method instead of wiring up
sock_no_{get,set}sockopt.

Signed-off-by: Christoph Hellwig 
Acked-by: Marc Kleine-Budde 
Signed-off-by: David S. Miller

crypto: af_alg - fix use-after-free in af_alg_accept() due to bh_lock_sock()

2020-06-18T07:09:54+00:00

The locking in af_alg_release_parent is broken as the BH socket
lock can only be taken if there is a code-path to handle the case
where the lock is owned by process-context.  Instead of adding
such handling, we can fix this by changing the ref counts to
atomic_t.

This patch also modifies the main refcnt to include both normal
and nokey sockets.  This way we don't have to fudge the nokey
ref count when a socket changes from nokey to normal.

Credits go to Mauricio Faria de Oliveira who diagnosed this bug
and sent a patch for it:

https://lore.kernel.org/linux-crypto/20200605161657.535043-1-mfo@canonical.com/

Reported-by: Brian Moyles 
Reported-by: Mauricio Faria de Oliveira 
Fixes: 37f96694cf73 ("crypto: af_alg - Use bh_lock_sock in...")
Cc: 
Signed-off-by: Herbert Xu