linux-stable.git/crypto, branch v6.5.7 Linux kernel stable tree crypto: sm2 - Fix crash caused by uninitialized context 2023-10-06T11:16:21+00:00 Tianjia Zhang tianjia.zhang@linux.alibaba.com 2023-09-18T08:38:50+00:00 3eb82c2bd446b0e0b9e8822a68b2f1d528849a86 commit 21155620fbf2edbb071144894ff9d67ba9a1faa0 upstream. In sm2_compute_z_digest() function, the newly allocated structure mpi_ec_ctx is used, but forget to initialize it, which will cause a crash when performing subsequent operations. Fixes: e5221fa6a355 ("KEYS: asymmetric: Move sm2 code into x509_public_key") Cc: stable@vger.kernel.org # v6.5 Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 21155620fbf2edbb071144894ff9d67ba9a1faa0 upstream.

In sm2_compute_z_digest() function, the newly allocated structure
mpi_ec_ctx is used, but forget to initialize it, which will cause
a crash when performing subsequent operations.

Fixes: e5221fa6a355 ("KEYS: asymmetric: Move sm2 code into x509_public_key")
Cc: stable@vger.kernel.org # v6.5
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
crypto: lrw,xts - Replace strlcpy with strscpy 2023-09-23T09:14:19+00:00 Azeem Shaikh azeemshaikh38@gmail.com 2023-06-20T20:08:32+00:00 72d4b63fbf2285684933b16f1c6bf1995680ad8c [ Upstream commit babb80b3ecc6f40c962e13c654ebcd27f25ee327 ] strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated [1]. In an effort to remove strlcpy() completely [2], replace strlcpy() here with strscpy(). Direct replacement is safe here since return value of -errno is used to check for truncation instead of sizeof(dest). [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [2] https://github.com/KSPP/linux/issues/89 Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit babb80b3ecc6f40c962e13c654ebcd27f25ee327 ]

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().

Direct replacement is safe here since return value of -errno
is used to check for truncation instead of sizeof(dest).

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
crypto: af_alg - Decrement struct key.usage in alg_set_by_key_serial() 2023-09-13T07:53:55+00:00 Frederick Lawler fred@cloudflare.com 2023-08-01T13:57:09+00:00 a424ccd65316502717ab18e9a5bd483bcc45716d commit 6b4b53ca0b7300ba2af98a49dbce22054bf034fe upstream. Calls to lookup_user_key() require a corresponding key_put() to decrement the usage counter. Once it reaches zero, we schedule key GC. Therefore decrement struct key.usage in alg_set_by_key_serial(). Fixes: 7984ceb134bf ("crypto: af_alg - Support symmetric encryption via keyring keys") Cc: <stable@vger.kernel.org> Signed-off-by: Frederick Lawler <fred@cloudflare.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6b4b53ca0b7300ba2af98a49dbce22054bf034fe upstream.

Calls to lookup_user_key() require a corresponding key_put() to
decrement the usage counter. Once it reaches zero, we schedule key GC.
Therefore decrement struct key.usage in alg_set_by_key_serial().

Fixes: 7984ceb134bf ("crypto: af_alg - Support symmetric encryption via keyring keys")
Cc: <stable@vger.kernel.org>
Signed-off-by: Frederick Lawler <fred@cloudflare.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
X.509: if signature is unsupported skip validation 2023-09-13T07:53:54+00:00 Thore Sommer public@thson.de 2023-08-15T11:29:42+00:00 e73a3c788735fcaba7f812af9b91409137a27d1a commit ef5b52a631f8c18353e80ccab8408b963305510c upstream. When the hash algorithm for the signature is not available the digest size is 0 and the signature in the certificate is marked as unsupported. When validating a self-signed certificate, this needs to be checked, because otherwise trying to validate the signature will fail with an warning: Loading compiled-in X.509 certificates WARNING: CPU: 0 PID: 1 at crypto/rsa-pkcs1pad.c:537 \ pkcs1pad_verify+0x46/0x12c ... Problem loading in-kernel X.509 certificate (-22) Signed-off-by: Thore Sommer <public@thson.de> Cc: stable@vger.kernel.org # v4.7+ Fixes: 6c2dc5ae4ab7 ("X.509: Extract signature digest and make self-signed cert checks earlier") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ef5b52a631f8c18353e80ccab8408b963305510c upstream.

When the hash algorithm for the signature is not available the digest size
is 0 and the signature in the certificate is marked as unsupported.

When validating a self-signed certificate, this needs to be checked,
because otherwise trying to validate the signature will fail with an
warning:

Loading compiled-in X.509 certificates
WARNING: CPU: 0 PID: 1 at crypto/rsa-pkcs1pad.c:537 \
pkcs1pad_verify+0x46/0x12c
...
Problem loading in-kernel X.509 certificate (-22)

Signed-off-by: Thore Sommer <public@thson.de>
Cc: stable@vger.kernel.org # v4.7+
Fixes: 6c2dc5ae4ab7 ("X.509: Extract signature digest and make self-signed cert checks earlier")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
crypto: api - Use work queue in crypto_destroy_instance 2023-09-13T07:53:05+00:00 Herbert Xu herbert@gondor.apana.org.au 2023-08-03T09:59:28+00:00 c0dbcebc7f390ec7dbe010dcc22c60f0c6bfc26d [ Upstream commit 9ae4577bc077a7e32c3c7d442c95bc76865c0f17 ] The function crypto_drop_spawn expects to be called in process context. However, when an instance is unregistered while it still has active users, the last user may cause the instance to be freed in atomic context. Fix this by delaying the freeing to a work queue. Fixes: 6bfd48096ff8 ("[CRYPTO] api: Added spawns") Reported-by: Florent Revest <revest@chromium.org> Reported-by: syzbot+d769eed29cc42d75e2a3@syzkaller.appspotmail.com Reported-by: syzbot+610ec0671f51e838436e@syzkaller.appspotmail.com Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Florent Revest <revest@chromium.org> Acked-by: Florent Revest <revest@chromium.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 9ae4577bc077a7e32c3c7d442c95bc76865c0f17 ]

The function crypto_drop_spawn expects to be called in process
context.  However, when an instance is unregistered while it still
has active users, the last user may cause the instance to be freed
in atomic context.

Fix this by delaying the freeing to a work queue.

Fixes: 6bfd48096ff8 ("[CRYPTO] api: Added spawns")
Reported-by: Florent Revest <revest@chromium.org>
Reported-by: syzbot+d769eed29cc42d75e2a3@syzkaller.appspotmail.com
Reported-by: syzbot+610ec0671f51e838436e@syzkaller.appspotmail.com
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Florent Revest <revest@chromium.org>
Acked-by: Florent Revest <revest@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
crypto: af_alg - Fix missing initialisation affecting gcm-aes-s390 2023-09-13T07:53:05+00:00 David Howells dhowells@redhat.com 2023-07-26T21:53:19+00:00 2c9d205040d7c0eaccc473917f9b0bb0a923e440 [ Upstream commit 6a4b8aa0a916b39a39175584c07222434fa6c6ef ] Fix af_alg_alloc_areq() to initialise areq->first_rsgl.sgl.sgt.sgl to point to the scatterlist array in areq->first_rsgl.sgl.sgl. Without this, the gcm-aes-s390 driver will oops when it tries to do gcm_walk_start() on req->dst because req->dst is set to the value of areq->first_rsgl.sgl.sgl by _aead_recvmsg() calling aead_request_set_crypt(). The problem comes if an empty ciphertext is passed: the loop in af_alg_get_rsgl() just passes straight out and doesn't set areq->first_rsgl up. This isn't a problem on x86_64 using gcmaes_crypt_by_sg() because, as far as I can tell, that ignores req->dst and only uses req->src[*]. [*] Is this a bug in aesni-intel_glue.c? The s390x oops looks something like: Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000a00000000 TEID: 0000000a00000803 Fault in home space mode while using kernel ASCE. AS:00000000a43a0007 R3:0000000000000024 Oops: 003b ilc:2 [#1] SMP ... Call Trace: [<000003ff7fc3d47e>] gcm_walk_start+0x16/0x28 [aes_s390] [<00000000a2a342f2>] crypto_aead_decrypt+0x9a/0xb8 [<00000000a2a60888>] aead_recvmsg+0x478/0x698 [<00000000a2e519a0>] sock_recvmsg+0x70/0xb0 [<00000000a2e51a56>] sock_read_iter+0x76/0xa0 [<00000000a273e066>] vfs_read+0x26e/0x2a8 [<00000000a273e8c4>] ksys_read+0xbc/0x100 [<00000000a311d808>] __do_syscall+0x1d0/0x1f8 [<00000000a312ff30>] system_call+0x70/0x98 Last Breaking-Event-Address: [<000003ff7fc3e6b4>] gcm_aes_crypt+0x104/0xa68 [aes_s390] Fixes: c1abe6f570af ("crypto: af_alg: Use extract_iter_to_sg() to create scatterlists") Reported-by: Ondrej Mosnáček <omosnacek@gmail.com> Link: https://lore.kernel.org/r/CAAUqJDuRkHE8fPgZJGaKjUjd3QfGwzfumuJBmStPqBhubxyk_A@mail.gmail.com/ Signed-off-by: David Howells <dhowells@redhat.com> cc: Herbert Xu <herbert@gondor.apana.org.au> cc: Sven Schnelle <svens@linux.ibm.com> cc: Harald Freudenberger <freude@linux.vnet.ibm.com> cc: "David S. Miller" <davem@davemloft.net> cc: Paolo Abeni <pabeni@redhat.com> cc: linux-crypto@vger.kernel.org cc: linux-s390@vger.kernel.org cc: regressions@lists.linux.dev Tested-by: Sven Schnelle <svens@linux.ibm.com> Tested-by: Ondrej Mosnáček <omosnacek@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 6a4b8aa0a916b39a39175584c07222434fa6c6ef ]

Fix af_alg_alloc_areq() to initialise areq->first_rsgl.sgl.sgt.sgl to point
to the scatterlist array in areq->first_rsgl.sgl.sgl.

Without this, the gcm-aes-s390 driver will oops when it tries to do
gcm_walk_start() on req->dst because req->dst is set to the value of
areq->first_rsgl.sgl.sgl by _aead_recvmsg() calling
aead_request_set_crypt().

The problem comes if an empty ciphertext is passed: the loop in
af_alg_get_rsgl() just passes straight out and doesn't set areq->first_rsgl
up.

This isn't a problem on x86_64 using gcmaes_crypt_by_sg() because, as far
as I can tell, that ignores req->dst and only uses req->src[*].

[*] Is this a bug in aesni-intel_glue.c?

The s390x oops looks something like:

 Unable to handle kernel pointer dereference in virtual kernel address space
 Failing address: 0000000a00000000 TEID: 0000000a00000803
 Fault in home space mode while using kernel ASCE.
 AS:00000000a43a0007 R3:0000000000000024
 Oops: 003b ilc:2 [#1] SMP
 ...
 Call Trace:
  [<000003ff7fc3d47e>] gcm_walk_start+0x16/0x28 [aes_s390]
  [<00000000a2a342f2>] crypto_aead_decrypt+0x9a/0xb8
  [<00000000a2a60888>] aead_recvmsg+0x478/0x698
  [<00000000a2e519a0>] sock_recvmsg+0x70/0xb0
  [<00000000a2e51a56>] sock_read_iter+0x76/0xa0
  [<00000000a273e066>] vfs_read+0x26e/0x2a8
  [<00000000a273e8c4>] ksys_read+0xbc/0x100
  [<00000000a311d808>] __do_syscall+0x1d0/0x1f8
  [<00000000a312ff30>] system_call+0x70/0x98
 Last Breaking-Event-Address:
  [<000003ff7fc3e6b4>] gcm_aes_crypt+0x104/0xa68 [aes_s390]

Fixes: c1abe6f570af ("crypto: af_alg: Use extract_iter_to_sg() to create scatterlists")
Reported-by: Ondrej Mosnáček <omosnacek@gmail.com>
Link: https://lore.kernel.org/r/CAAUqJDuRkHE8fPgZJGaKjUjd3QfGwzfumuJBmStPqBhubxyk_A@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: Sven Schnelle <svens@linux.ibm.com>
cc: Harald Freudenberger <freude@linux.vnet.ibm.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-crypto@vger.kernel.org
cc: linux-s390@vger.kernel.org
cc: regressions@lists.linux.dev
Tested-by: Sven Schnelle <svens@linux.ibm.com>
Tested-by: Ondrej Mosnáček <omosnacek@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
crypto: fix uninit-value in af_alg_free_resources 2023-08-18T10:30:09+00:00 Pavel Skripkin paskripkin@gmail.com 2023-08-14T18:03:41+00:00 080aa61e370b9c5cafe71cacadbfe0e72db4d6df Syzbot was able to trigger use of uninitialized memory in af_alg_free_resources. Bug is caused by missing initialization of rsgl->sgl.need_unpin before adding to rsgl_list. Then in case of extract_iter_to_sg() failure, rsgl is left with uninitialized need_unpin which is read during clean up BUG: KMSAN: uninit-value in af_alg_free_sg crypto/af_alg.c:545 [inline] BUG: KMSAN: uninit-value in af_alg_free_areq_sgls crypto/af_alg.c:778 [inline] BUG: KMSAN: uninit-value in af_alg_free_resources+0x3d1/0xf60 crypto/af_alg.c:1117 af_alg_free_sg crypto/af_alg.c:545 [inline] af_alg_free_areq_sgls crypto/af_alg.c:778 [inline] af_alg_free_resources+0x3d1/0xf60 crypto/af_alg.c:1117 _skcipher_recvmsg crypto/algif_skcipher.c:144 [inline] ... Uninit was created at: slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767 slab_alloc_node mm/slub.c:3470 [inline] __kmem_cache_alloc_node+0x536/0x8d0 mm/slub.c:3509 __do_kmalloc_node mm/slab_common.c:984 [inline] __kmalloc+0x121/0x3c0 mm/slab_common.c:998 kmalloc include/linux/slab.h:586 [inline] sock_kmalloc+0x128/0x1c0 net/core/sock.c:2683 af_alg_alloc_areq+0x41/0x2a0 crypto/af_alg.c:1188 _skcipher_recvmsg crypto/algif_skcipher.c:71 [inline] Fixes: c1abe6f570af ("crypto: af_alg: Use extract_iter_to_sg() to create scatterlists") Reported-and-tested-by: syzbot+cba21d50095623218389@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=cba21d50095623218389 Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> 
Syzbot was able to trigger use of uninitialized memory in
af_alg_free_resources.

Bug is caused by missing initialization of rsgl->sgl.need_unpin before
adding to rsgl_list. Then in case of extract_iter_to_sg() failure, rsgl
is left with uninitialized need_unpin which is read during clean up

BUG: KMSAN: uninit-value in af_alg_free_sg crypto/af_alg.c:545 [inline]
BUG: KMSAN: uninit-value in af_alg_free_areq_sgls crypto/af_alg.c:778 [inline]
BUG: KMSAN: uninit-value in af_alg_free_resources+0x3d1/0xf60 crypto/af_alg.c:1117
 af_alg_free_sg crypto/af_alg.c:545 [inline]
 af_alg_free_areq_sgls crypto/af_alg.c:778 [inline]
 af_alg_free_resources+0x3d1/0xf60 crypto/af_alg.c:1117
 _skcipher_recvmsg crypto/algif_skcipher.c:144 [inline]
...

Uninit was created at:
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3470 [inline]
 __kmem_cache_alloc_node+0x536/0x8d0 mm/slub.c:3509
 __do_kmalloc_node mm/slab_common.c:984 [inline]
 __kmalloc+0x121/0x3c0 mm/slab_common.c:998
 kmalloc include/linux/slab.h:586 [inline]
 sock_kmalloc+0x128/0x1c0 net/core/sock.c:2683
 af_alg_alloc_areq+0x41/0x2a0 crypto/af_alg.c:1188
 _skcipher_recvmsg crypto/algif_skcipher.c:71 [inline]

Fixes: c1abe6f570af ("crypto: af_alg: Use extract_iter_to_sg() to create scatterlists")
Reported-and-tested-by: syzbot+cba21d50095623218389@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=cba21d50095623218389
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto: algif_hash - Fix race between MORE and non-MORE sends 2023-07-08T12:48:42+00:00 David Howells dhowells@redhat.com 2023-07-07T09:12:38+00:00 0b7ec177b589842c0abf9e91459c83ba28d32452 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 <dhowells@redhat.com> Tested-by: syzbot+689ec3afb1ef07b766b2@syzkaller.appspotmail.com cc: Herbert Xu <herbert@gondor.apana.org.au> cc: Paolo Abeni <pabeni@redhat.com> cc: "David S. Miller" <davem@davemloft.net> cc: Eric Dumazet <edumazet@google.com> cc: Jakub Kicinski <kuba@kernel.org> cc: linux-crypto@vger.kernel.org cc: netdev@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> 
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 <dhowells@redhat.com>
Tested-by: syzbot+689ec3afb1ef07b766b2@syzkaller.appspotmail.com
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: Paolo Abeni <pabeni@redhat.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
KEYS: asymmetric: Fix error codes 2023-07-07T04:16:47+00:00 Dan Carpenter dan.carpenter@linaro.org 2023-07-03T14:18:08+00:00 9e9311e04e63ede92be98425efd843f9836336bd These error paths should return the appropriate error codes instead of returning success. Fixes: 63ba4d67594a ("KEYS: asymmetric: Use new crypto interface without scatterlists") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> 
These error paths should return the appropriate error codes instead of
returning success.

Fixes: 63ba4d67594a ("KEYS: asymmetric: Use new crypto interface without scatterlists")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto: af_alg - Fix merging of written data into spliced pages 2023-07-05T08:14:24+00:00 David Howells dhowells@redhat.com 2023-07-04T15:56:24+00:00 d3dccb0a487d065ce097e565d9ca8ae85d892a55 af_alg_sendmsg() takes data-to-be-copied that's provided by write(), send(), sendmsg() and similar into pages that it allocates and will merge new data into the last page in the list, based on the value of ctx->merge. Now that af_alg_sendmsg() accepts MSG_SPLICE_PAGES, it adds spliced pages directly into the list and then incorrectly appends data to them if there's space left because ctx->merge says that it can. This was cleared by af_alg_sendpage(), but that got lost. Fix this by skipping the merge if MSG_SPLICE_PAGES is specified and clearing ctx->merge after MSG_SPLICE_PAGES has added stuff to the list. Fixes: bf63e250c4b1 ("crypto: af_alg: Support MSG_SPLICE_PAGES") Reported-by: Ondrej Mosnáček <omosnacek@gmail.com> Link: https://lore.kernel.org/r/CAAUqJDvFuvms55Td1c=XKv6epfRnnP78438nZQ-JKyuCptGBiQ@mail.gmail.com/ Signed-off-by: David Howells <dhowells@redhat.com> cc: Herbert Xu <herbert@gondor.apana.org.au> cc: Paolo Abeni <pabeni@redhat.com> cc: "David S. Miller" <davem@davemloft.net> cc: Eric Dumazet <edumazet@google.com> cc: Jakub Kicinski <kuba@kernel.org> cc: linux-crypto@vger.kernel.org cc: netdev@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> 
af_alg_sendmsg() takes data-to-be-copied that's provided by write(),
send(), sendmsg() and similar into pages that it allocates and will merge
new data into the last page in the list, based on the value of ctx->merge.

Now that af_alg_sendmsg() accepts MSG_SPLICE_PAGES, it adds spliced pages
directly into the list and then incorrectly appends data to them if there's
space left because ctx->merge says that it can.  This was cleared by
af_alg_sendpage(), but that got lost.

Fix this by skipping the merge if MSG_SPLICE_PAGES is specified and
clearing ctx->merge after MSG_SPLICE_PAGES has added stuff to the list.

Fixes: bf63e250c4b1 ("crypto: af_alg: Support MSG_SPLICE_PAGES")
Reported-by: Ondrej Mosnáček <omosnacek@gmail.com>
Link: https://lore.kernel.org/r/CAAUqJDvFuvms55Td1c=XKv6epfRnnP78438nZQ-JKyuCptGBiQ@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: Paolo Abeni <pabeni@redhat.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>