Commit Graph

11 Commits

Author SHA1 Message Date
Dinghao Liu 5501892826 ubifs: Fix memleak in ubifs_init_authentication
[ Upstream commit 11b8ab3836454a2600e396f34731e491b661f9d5 ]

When crypto_shash_digestsize() fails, c->hmac_tfm
has not been freed before returning, which leads
to memleak.

Fixes: 49525e5eec ("ubifs: Add helper functions for authentication support")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04 10:26:25 +01:00
Wang ShaoBo a37d283825 ubifs: Fix error return code in ubifs_init_authentication()
[ Upstream commit 3cded66330591cfd2554a3fd5edca8859ea365a2 ]

Fix to return PTR_ERR() error code from the error handling case where
ubifs_hash_get_desc() failed instead of 0 in ubifs_init_authentication(),
as done elsewhere in this function.

Fixes: 49525e5eec ("ubifs: Add helper functions for authentication support")
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:25 +01:00
Eric Biggers 3be8ece114 ubifs: fix wrong use of crypto_shash_descsize()
[ Upstream commit 3c3c32f85b6cc05e5db78693457deff03ac0f434 ]

crypto_shash_descsize() returns the size of the shash_desc context
needed to compute the hash, not the size of the hash itself.

crypto_shash_digestsize() would be correct, or alternatively using
c->hash_len and c->hmac_desc_len which already store the correct values.
But actually it's simpler to just use stack arrays, so do that instead.

Fixes: 49525e5eec ("ubifs: Add helper functions for authentication support")
Fixes: da8ef65f95 ("ubifs: Authenticate replayed journal")
Cc: <stable@vger.kernel.org> # v4.20+
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 17:46:09 +02:00
Wenwen Wang 7992e00469 ubifs: Fix memory leak in __ubifs_node_verify_hmac error path
In __ubifs_node_verify_hmac(), 'hmac' is allocated through kmalloc().
However, it is not deallocated in the following execution if
ubifs_node_calc_hmac() fails, leading to a memory leak bug. To fix this
issue, free 'hmac' before returning the error.

Fixes: 49525e5eec ("ubifs: Add helper functions for authentication support")
Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: Richard Weinberger <richard@nod.at>
2019-09-15 22:11:58 +02:00
Sascha Hauer 817aa09484 ubifs: support offline signed images
HMACs can only be generated on the system the UBIFS image is running on.
To support offline signed images we add a PKCS#7 signature to the UBIFS
image which can be created by mkfs.ubifs.

Both the master node and the superblock need to be authenticated, during
normal runtime both are protected with HMACs. For offline signature
support however only a single signature is desired. We add a signature
covering the superblock node directly behind it. To protect the master
node a hash of the master node is added to the superblock which is used
when the master node doesn't contain a HMAC.

Transition to a read/write filesystem is also supported. During
transition first the master node is rewritten with a HMAC (implicitly,
it is written anyway as the FS is marked dirty). Afterwards the
superblock is rewritten with a HMAC. Once after the image has been
mounted read/write it is HMAC only, the signature is no longer required
or even present on the filesystem.

In an offline signed image the master node is authenticated by the
superblock. In a transition to r/w we have to make sure that the master
node is rewritten before the superblock node. In this case the master
node gets a HMAC and its authenticity no longer depends on the
superblock node. There are some cases in which the current code first
writes the superblock node though, so with this patch writing of the
superblock node is delayed until the master node is written.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2019-07-08 19:43:52 +02:00
Linus Torvalds d7a02fa0a8 This pull request contains the following changes for UBI/UBIFS
- fscrypt framework usage updates
 - One huge fix for xattr unlink
 - Cleanup of fscrypt ifdefs
 - Fix for our new UBIFS auth feature
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Merge tag 'upstream-5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/rw/ubifs

Pull UBI/UBIFS updates from Richard Weinberger:

 - fscrypt framework usage updates

 - One huge fix for xattr unlink

 - Cleanup of fscrypt ifdefs

 - Fix for our new UBIFS auth feature

* tag 'upstream-5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubi: wl: Fix uninitialized variable
  ubifs: Drop unnecessary setting of zbr->znode
  ubifs: Remove ifdefs around CONFIG_UBIFS_ATIME_SUPPORT
  ubifs: Remove #ifdef around CONFIG_FS_ENCRYPTION
  ubifs: Limit number of xattrs per inode
  ubifs: orphan: Handle xattrs like files
  ubifs: journal: Handle xattrs like files
  ubifs: find.c: replace swap function with built-in one
  ubifs: Do not skip hash checking in data nodes
  ubifs: work around high stack usage with clang
  ubifs: remove unused function __ubifs_shash_final
  ubifs: remove unnecessary #ifdef around fscrypt_ioctl_get_policy()
  ubifs: remove unnecessary calls to set up directory key
2019-05-12 18:16:31 -04:00
Arnd Bergmann f4844b35d6 ubifs: work around high stack usage with clang
Building this file with clang can result in large stack usage as seen from
this warning:

fs/ubifs/auth.c:78:5: error: stack frame size of 1152 bytes in function 'ubifs_prepare_auth_node'

The problem is that inlining ubifs_hash_calc_hmac() leads to
two SHASH_DESC_ON_STACK() blocks in the same function, and clang
for some reason does not reuse the stack space as it should.

Putting the first declaration into a separate basic block avoids
this problem and reduces the stack allocation to 640 bytes.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2019-05-07 21:36:39 +02:00
YueHaibing fb9a5a3edb ubifs: remove unused function __ubifs_shash_final
There is no callers in tree, and can be removed.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
2019-05-07 21:36:39 +02:00
Eric Biggers 877b5691f2 crypto: shash - remove shash_desc::flags
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.

With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP.  These would all need to be fixed if any shash algorithm
actually started sleeping.  For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API.  However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.

Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk.  It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.

Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-25 15:38:12 +08:00
Eric Biggers 3d234b3313 crypto: drop mask=CRYPTO_ALG_ASYNC from 'shash' tfm allocations
'shash' algorithms are always synchronous, so passing CRYPTO_ALG_ASYNC
in the mask to crypto_alloc_shash() has no effect.  Many users therefore
already don't pass it, but some still do.  This inconsistency can cause
confusion, especially since the way the 'mask' argument works is
somewhat counterintuitive.

Thus, just remove the unneeded CRYPTO_ALG_ASYNC flags.

This patch shouldn't change any actual behavior.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:55 +08:00
Sascha Hauer 49525e5eec ubifs: Add helper functions for authentication support
This patch adds the various helper functions needed for authentication
support. We need functions to hash nodes, to embed HMACs into a node and
to compare hashes and HMACs. Most functions first check if this
filesystem is authenticated and bail out early if not, which makes the
functions safe to be called with disabled authentication.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23 13:48:33 +02:00