kernel/linux.git/security/integrity/evm, branch v5.4.209

Revert "evm: Fix memleak in init_desc"

2022-07-21T18:59:18+00:00

commit 51dd64bb99e4478fc5280171acd8e1b529eadaf7 upstream. This reverts commit ccf11dbaa07b328fa469415c362d33459c140a37. Commit ccf11dbaa07b ("evm: Fix memleak in init_desc") said there is memleak in init_desc. That may be incorrect, as we can see, tmp_tfm is saved in one of the two global variables hmac_tfm or evm_tfm[hash_algo], then if init_desc is called next time, there is no need to alloc tfm again, so in the error path of kmalloc desc or crypto_shash_init(desc), It is not a problem without freeing tmp_tfm. And also that commit did not reset the global variable to NULL after freeing tmp_tfm and this makes *tfm a dangling pointer which may cause a UAF issue. Reported-by: Guozihua (Scott) Signed-off-by: Xiu Jianfeng Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

evm: mark evm_fixmode as __ro_after_init

2021-11-17T08:48:23+00:00

commit 32ba540f3c2a7ef61ed5a577ce25069a3d714fc9 upstream. The evm_fixmode is only configurable by command-line option and it is never modified outside initcalls, so declaring it with __ro_after_init is better. Signed-off-by: Austin Kim Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

evm: fix writing /evm overflow

2021-07-14T14:53:21+00:00

[ Upstream commit 49219d9b8785ba712575c40e48ce0f7461254626 ] EVM_SETUP_COMPLETE is defined as 0x80000000, which is larger than INT_MAX. The "-fno-strict-overflow" compiler option properly prevents signaling EVM that the EVM policy setup is complete. Define and read an unsigned int. Fixes: f00d79750712 ("EVM: Allow userspace to signal an RSA key has been loaded") Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

evm: Refuse EVM_ALLOW_METADATA_WRITES only if an HMAC key is loaded

2021-07-14T14:53:08+00:00

commit 9acc89d31f0c94c8e573ed61f3e4340bbd526d0c upstream. EVM_ALLOW_METADATA_WRITES is an EVM initialization flag that can be set to temporarily disable metadata verification until all xattrs/attrs necessary to verify an EVM portable signature are copied to the file. This flag is cleared when EVM is initialized with an HMAC key, to avoid that the HMAC is calculated on unverified xattrs/attrs. Currently EVM unnecessarily denies setting this flag if EVM is initialized with a public key, which is not a concern as it cannot be used to trust xattrs/attrs updates. This patch removes this limitation. Fixes: ae1ba1676b88e ("EVM: Allow userland to permit modification of EVM-protected metadata") Signed-off-by: Roberto Sassu Cc: stable@vger.kernel.org # 4.16.x Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

evm: Execute evm_inode_init_security() only when an HMAC key is loaded

2021-07-14T14:53:08+00:00

commit 9eea2904292c2d8fa98df141d3bf7c41ec9dc1b5 upstream. evm_inode_init_security() requires an HMAC key to calculate the HMAC on initial xattrs provided by LSMs. However, it checks generically whether a key has been loaded, including also public keys, which is not correct as public keys are not suitable to calculate the HMAC. Originally, support for signature verification was introduced to verify a possibly immutable initial ram disk, when no new files are created, and to switch to HMAC for the root filesystem. By that time, an HMAC key should have been loaded and usable to calculate HMACs for new files. More recently support for requiring an HMAC key was removed from the kernel, so that signature verification can be used alone. Since this is a legitimate use case, evm_inode_init_security() should not return an error when no HMAC key has been loaded. This patch fixes this problem by replacing the evm_key_loaded() check with a check of the EVM_INIT_HMAC flag in evm_initialized. Fixes: 26ddabfe96b ("evm: enable EVM when X509 certificate is loaded") Signed-off-by: Roberto Sassu Cc: stable@vger.kernel.org # 4.5.x Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

evm: Fix memleak in init_desc

2021-03-04T09:26:21+00:00

[ Upstream commit ccf11dbaa07b328fa469415c362d33459c140a37 ] tmp_tfm is allocated, but not freed on subsequent kmalloc failure, which leads to a memory leak. Free tmp_tfm. Fixes: d46eb3699502b ("evm: crypto hash replaced by shash") Signed-off-by: Dinghao Liu [zohar@linux.ibm.com: formatted/reworded patch description] Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

evm: Check size of security.evm before using it

2020-11-01T11:01:05+00:00

commit 455b6c9112eff8d249e32ba165742085678a80a4 upstream. This patch checks the size for the EVM_IMA_XATTR_DIGSIG and EVM_XATTR_PORTABLE_DIGSIG types to ensure that the algorithm is read from the buffer returned by vfs_getxattr_alloc(). Cc: stable@vger.kernel.org # 4.19.x Fixes: 5feeb61183dde ("evm: Allow non-SHA1 digital signatures") Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

evm: Fix possible memory leak in evm_calc_hmac_or_hash()

2020-06-22T07:31:15+00:00

commit 0c4395fb2aa77341269ea619c5419ea48171883f upstream. Don't immediately return if the signature is portable and security.ima is not present. Just set error so that memory allocated is freed before returning from evm_calc_hmac_or_hash(). Fixes: 50b977481fce9 ("EVM: Add support for portable signature format") Signed-off-by: Roberto Sassu Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

evm: Fix RCU list related warnings

2020-06-07T11:18:50+00:00

[ Upstream commit 770f60586d2af0590be263f55fd079226313922c ] This patch fixes the following warning and few other instances of traversal of evm_config_xattrnames list: [ 32.848432] ============================= [ 32.848707] WARNING: suspicious RCU usage [ 32.848966] 5.7.0-rc1-00006-ga8d5875ce5f0b #1 Not tainted [ 32.849308] ----------------------------- [ 32.849567] security/integrity/evm/evm_main.c:231 RCU-list traversed in non-reader section!! Since entries are only added to the list and never deleted, use list_for_each_entry_lockless() instead of list_for_each_entry_rcu for traversing the list. Also, add a relevant comment in evm_secfs.c to indicate this fact. Reported-by: kernel test robot Suggested-by: Paul E. McKenney Signed-off-by: Madhuparna Bhowmik Acked-by: Paul E. McKenney (RCU viewpoint) Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

evm: Fix a small race in init_desc()

2020-05-27T15:46:17+00:00

[ Upstream commit 8433856947217ebb5697a8ff9c4c9cad4639a2cf ] The IS_ERR_OR_NULL() function has two conditions and if we got really unlucky we could hit a race where "ptr" started as an error pointer and then was set to NULL. Both conditions would be false even though the pointer at the end was NULL. This patch fixes the problem by ensuring that "*tfm" can only be NULL or valid. I have introduced a "tmp_tfm" variable to make that work. I also reversed a condition and pulled the code in one tab. Reported-by: Roberto Sassu Fixes: 53de3b080d5e ("evm: Check also if *tfm is an error pointer in init_desc()") Signed-off-by: Dan Carpenter Acked-by: Roberto Sassu Acked-by: Krzysztof Struczynski Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin