In the quest to remove all stack VLA usage from the kernel[1], this
replaces struct crypto_skcipher and SKCIPHER_REQUEST_ON_STACK() usage
with struct crypto_sync_skcipher and SYNC_SKCIPHER_REQUEST_ON_STACK(),
which uses a fixed stack size.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Cc: "Leonidas S. Barbosa" <leosilva@linux.vnet.ibm.com>
Cc: Paulo Flabiano Smorigo <pfsmorigo@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes sleep-in-atomic bugs in AES-CBC and AES-XTS VMX
implementations. The problem is that the blkcipher_* functions should
not be called in atomic context.
The bugs can be reproduced via the AF_ALG interface by trying to
encrypt/decrypt sufficiently large buffers (at least 64 KiB) using the
VMX implementations of 'cbc(aes)' or 'xts(aes)'. Such operations then
trigger BUG in crypto_yield():
[ 891.863680] BUG: sleeping function called from invalid context at include/crypto/algapi.h:424
[ 891.864622] in_atomic(): 1, irqs_disabled(): 0, pid: 12347, name: kcapi-enc
[ 891.864739] 1 lock held by kcapi-enc/12347:
[ 891.864811] #0: 00000000f5d42c46 (sk_lock-AF_ALG){+.+.}, at: skcipher_recvmsg+0x50/0x530
[ 891.865076] CPU: 5 PID: 12347 Comm: kcapi-enc Not tainted 4.19.0-0.rc0.git3.1.fc30.ppc64le #1
[ 891.865251] Call Trace:
[ 891.865340] [c0000003387578c0] [c000000000d67ea4] dump_stack+0xe8/0x164 (unreliable)
[ 891.865511] [c000000338757910] [c000000000172a58] ___might_sleep+0x2f8/0x310
[ 891.865679] [c000000338757990] [c0000000006bff74] blkcipher_walk_done+0x374/0x4a0
[ 891.865825] [c0000003387579e0] [d000000007e73e70] p8_aes_cbc_encrypt+0x1c8/0x260 [vmx_crypto]
[ 891.865993] [c000000338757ad0] [c0000000006c0ee0] skcipher_encrypt_blkcipher+0x60/0x80
[ 891.866128] [c000000338757b10] [c0000000006ec504] skcipher_recvmsg+0x424/0x530
[ 891.866283] [c000000338757bd0] [c000000000b00654] sock_recvmsg+0x74/0xa0
[ 891.866403] [c000000338757c10] [c000000000b00f64] ___sys_recvmsg+0xf4/0x2f0
[ 891.866515] [c000000338757d90] [c000000000b02bb8] __sys_recvmsg+0x68/0xe0
[ 891.866631] [c000000338757e30] [c00000000000bbe4] system_call+0x5c/0x70
Fixes: 8c755ace35 ("crypto: vmx - Adding CBC routines for VMX module")
Fixes: c07f5d3da6 ("crypto: vmx - Adding support for XTS")
Cc: stable@vger.kernel.org
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In p8_aes_xts_init() we do a printk(KERN_INFO ...) to report the
fallback implementation we're using. However with a slow console this
can significantly affect the speed of crypto operations. So remove it.
Fixes: c07f5d3da6 ("crypto: vmx - Adding support for XTS")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
You can't reach init() if parent alg_name is invalid. Moreover,
cypto_alloc_base() will return ENOENT if alg_name is NULL.
Found while grasping the fallback mechanism.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
walk.iv is not assigned a value in blkcipher_walk_init. It makes iv uninitialized.
It is possibly a null value(as shown below), which is then used by aes_p8_encrypt.
This patch moves iv = walk.iv after blkcipher_walk_virt, in which walk.iv is set.
[17856.268050] Unable to handle kernel paging request for data at address 0x00000000
[17856.268212] Faulting instruction address: 0xd000000002ff04bc
7:mon> t
[link register ] d000000002ff47b8 p8_aes_xts_crypt+0x168/0x2a0 [vmx_crypto] (938)
[c000000013b77960] d000000002ff4794 p8_aes_xts_crypt+0x144/0x2a0 [vmx_crypto] (unreliable)
[c000000013b77a70] c000000000544d64 skcipher_decrypt_blkcipher+0x64/0x80
[c000000013b77ac0] d000000003c0175c crypt_convert+0x53c/0x620 [dm_crypt]
[c000000013b77ba0] d000000003c043fc kcryptd_crypt+0x3cc/0x440 [dm_crypt]
[c000000013b77c50] c0000000000f3070 process_one_work+0x1e0/0x590
[c000000013b77ce0] c0000000000f34c8 worker_thread+0xa8/0x660
[c000000013b77d80] c0000000000fc0b0 kthread+0x110/0x130
[c000000013b77e30] c0000000000098f0 ret_from_kernel_thread+0x5c/0x6c
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch add XTS support using VMX-crypto driver.
Signed-off-by: Leonidas S. Barbosa <leosilva@linux.vnet.ibm.com>
Signed-off-by: Paulo Flabiano Smorigo <pfsmorigo@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Kees Cook