#
a652aa59 |
| 23-Feb-2024 |
Stefan Berger <stefanb@linux.ibm.com> |
evm: Store and detect metadata inode attributes changes
On stacked filesystem the metadata inode may be different than the one file data inode and therefore changes to it need to be detected indepen
evm: Store and detect metadata inode attributes changes
On stacked filesystem the metadata inode may be different than the one file data inode and therefore changes to it need to be detected independently. Therefore, store the i_version, device number, and inode number associated with the file metadata inode.
Implement a function to detect changes to the inode and if a change is detected reset the evm_status. This function will be called by IMA when IMA detects that the metadata inode is different from the file's inode.
Co-developed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
faf99481 |
| 23-Feb-2024 |
Stefan Berger <stefanb@linux.ibm.com> |
evm: Use the metadata inode to calculate metadata hash
Changes to file attributes (mode bits, uid, gid) on the lower layer are not taken into account when d_backing_inode() is used when a file is ac
evm: Use the metadata inode to calculate metadata hash
Changes to file attributes (mode bits, uid, gid) on the lower layer are not taken into account when d_backing_inode() is used when a file is accessed on the overlay layer and this file has not yet been copied up. This is because d_backing_inode() does not return the real inode of the lower layer but instead returns the backing inode which in this case holds wrong file attributes. Further, when CONFIG_OVERLAY_FS_METACOPY is enabled and a copy-up is triggered due to file metadata changes, then the metadata are held by the backing inode while the data are still held by the real inode. Therefore, use d_inode(d_real(dentry, D_REAL_METADATA)) to get to the file's metadata inode and use it to calculate the metadata hash with.
Co-developed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Acked-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
75a323e6 |
| 15-Feb-2024 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Make it independent from 'integrity' LSM
Define a new structure for EVM-specific metadata, called evm_iint_cache, and embed it in the inode security blob. Introduce evm_iint_inode() to retrieve
evm: Make it independent from 'integrity' LSM
Define a new structure for EVM-specific metadata, called evm_iint_cache, and embed it in the inode security blob. Introduce evm_iint_inode() to retrieve metadata, and register evm_inode_alloc_security() for the inode_alloc_security LSM hook, to initialize the structure (before splitting metadata, this task was done by iint_init_always()).
Keep the non-NULL checks after calling evm_iint_inode() except in evm_inode_alloc_security(), to take into account inodes for which security_inode_alloc() was not called. When using shared metadata, obtaining a NULL pointer from integrity_iint_find() meant that the file wasn't in the IMA policy. Now, because IMA and EVM use disjoint metadata, the EVM status has to be stored for every inode regardless of the IMA policy.
Given that from now on EVM relies on its own metadata, remove the iint parameter from evm_verifyxattr(). Also, directly retrieve the iint in evm_verify_hmac(), called by both evm_verifyxattr() and evm_verify_current_integrity(), since now there is no performance penalty in retrieving EVM metadata (constant time).
Replicate the management of the IMA_NEW_FILE flag, by introducing evm_post_path_mknod() and evm_file_release() to respectively set and clear the newly introduced flag EVM_NEW_FILE, at the same time IMA does. Like for IMA, select CONFIG_SECURITY_PATH when EVM is enabled, to ensure that files are marked as new.
Unlike ima_post_path_mknod(), evm_post_path_mknod() cannot check if a file must be appraised. Thus, it marks all affected files. Also, it does not clear EVM_NEW_FILE depending on i_version, but that is not a problem because IMA_NEW_FILE is always cleared when set in ima_check_last_writer().
Move the EVM-specific flag EVM_IMMUTABLE_DIGSIG to security/integrity/evm/evm.h, since that definition is now unnecessary in the common integrity layer.
Finally, switch to the LSM reservation mechanism for the EVM xattr, and consequently decrement by one the number of xattrs to allocate in security_inode_init_security().
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
c31288e5 |
| 10-Jun-2023 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Support multiple LSMs providing an xattr
Currently, evm_inode_init_security() processes a single LSM xattr from the array passed by security_inode_init_security(), and calculates the HMAC on it
evm: Support multiple LSMs providing an xattr
Currently, evm_inode_init_security() processes a single LSM xattr from the array passed by security_inode_init_security(), and calculates the HMAC on it and other inode metadata.
As the LSM infrastructure now can pass to EVM an array with multiple xattrs, scan them until the terminator (xattr name NULL), and calculate the HMAC on all of them.
Also, double check that the xattrs array terminator is the first non-filled slot (obtained with lsm_get_xattr_slot()). Consumers of the xattrs array, such as the initxattrs() callbacks, rely on the terminator.
Finally, change the name of the lsm_xattr parameter of evm_init_hmac() to xattrs, to reflect the new type of information passed.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
996e0a97 |
| 06-Jun-2023 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Fix build warnings
Fix build warnings (function parameters description) for evm_read_protected_xattrs(), evm_set_key() and evm_verifyxattr().
Fixes: 7626676320f3 ("evm: provide a function to s
evm: Fix build warnings
Fix build warnings (function parameters description) for evm_read_protected_xattrs(), evm_set_key() and evm_verifyxattr().
Fixes: 7626676320f3 ("evm: provide a function to set the EVM key from the kernel") # v4.5+ Fixes: 8314b6732ae4 ("ima: Define new template fields xattrnames, xattrlengths and xattrvalues") # v5.14+ Fixes: 2960e6cb5f7c ("evm: additional parameter to pass integrity cache entry 'iint'") # v3.2+ Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
8250865c |
| 31-Jan-2023 |
Xiu Jianfeng <xiujianfeng@huawei.com> |
evm: call dump_security_xattr() in all cases to remove code duplication
Currently dump_security_xattr() is used to dump security xattr value which is larger than 64 bytes, otherwise, pr_debug() is u
evm: call dump_security_xattr() in all cases to remove code duplication
Currently dump_security_xattr() is used to dump security xattr value which is larger than 64 bytes, otherwise, pr_debug() is used. In order to remove code duplication, refactor dump_security_xattr() and call it in all cases.
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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|
#
39f60c1c |
| 13-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port xattr to mnt_idmap
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conver
fs: port xattr to mnt_idmap
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
4609e1f1 |
| 13-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port ->permission() to pass mnt_idmap
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is j
fs: port ->permission() to pass mnt_idmap
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
f6fbd8cb |
| 09-Nov-2022 |
Paul Moore <paul@paul-moore.com> |
lsm,fs: fix vfs_getxattr_alloc() return type and caller error paths
The vfs_getxattr_alloc() function currently returns a ssize_t value despite the fact that it only uses int values internally for r
lsm,fs: fix vfs_getxattr_alloc() return type and caller error paths
The vfs_getxattr_alloc() function currently returns a ssize_t value despite the fact that it only uses int values internally for return values. Fix this by converting vfs_getxattr_alloc() to return an int type and adjust the callers as necessary. As part of these caller modifications, some of the callers are fixed to properly free the xattr value buffer on both success and failure to ensure that memory is not leaked in the failure case.
Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
51dd64bb |
| 27-May-2022 |
Xiu Jianfeng <xiujianfeng@huawei.com> |
Revert "evm: Fix memleak in init_desc"
This reverts commit ccf11dbaa07b328fa469415c362d33459c140a37.
Commit ccf11dbaa07b ("evm: Fix memleak in init_desc") said there is memleak in init_desc. That m
Revert "evm: Fix memleak in init_desc"
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) <guozihua@huawei.com> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
4c41186f |
| 13-May-2022 |
Stefan Berger <stefanb@linux.ibm.com> |
evm: Clean up some variables
Make hmac_tfm static since it's not used anywhere else besides the file it is in.
Remove declaration of hash_tfm since it doesn't exist.
Signed-off-by: Stefan Berger <
evm: Clean up some variables
Make hmac_tfm static since it's not used anywhere else besides the file it is in.
Remove declaration of hash_tfm since it doesn't exist.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
907a399d |
| 21-Jun-2021 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Check xattr size discrepancy between kernel and user
The kernel and the user obtain an xattr value in two different ways:
kernel (EVM): uses vfs_getxattr_alloc() which obtains the xattr value
evm: Check xattr size discrepancy between kernel and user
The kernel and the user obtain an xattr value in two different ways:
kernel (EVM): uses vfs_getxattr_alloc() which obtains the xattr value from the filesystem handler (raw value);
user (ima-evm-utils): uses vfs_getxattr() which obtains the xattr value from the LSMs (normalized value).
Normally, this does not have an impact unless security.selinux is set with setfattr, with a value not terminated by '\0' (this is not the recommended way, security.selinux should be set with the appropriate tools such as chcon and restorecon).
In this case, the kernel and the user see two different xattr values: the former sees the xattr value without '\0' (raw value), the latter sees the value with '\0' (value normalized by SELinux).
This could result in two different verification outcomes from EVM and ima-evm-utils, if a signature was calculated with a security.selinux value terminated by '\0' and the value set in the filesystem is not terminated by '\0'. The former would report verification failure due to the missing '\0', while the latter would report verification success (because it gets the normalized value with '\0').
This patch mitigates this issue by comparing in evm_calc_hmac_or_hash() the size of the xattr returned by the two xattr functions and by warning the user if there is a discrepancy.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
87ac3d00 |
| 13-May-2021 |
Mimi Zohar <zohar@linux.ibm.com> |
evm: output EVM digest calculation info
Output the data used in calculating the EVM digest and the resulting digest as ascii hexadecimal strings.
Suggested-by: Lakshmi Ramasubramanian <nramas@linux
evm: output EVM digest calculation info
Output the data used in calculating the EVM digest and the resulting digest as ascii hexadecimal strings.
Suggested-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> (CONFIG_DYNAMIC_DEBUG) Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Reported-by: kernel test robot <lkp@intel.com> (Use %zu for size_t) Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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|
#
8c7a703e |
| 28-May-2021 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Verify portable signatures against all protected xattrs
Currently, the evm_config_default_xattrnames array contains xattr names only related to LSMs which are enabled in the kernel configuratio
evm: Verify portable signatures against all protected xattrs
Currently, the evm_config_default_xattrnames array contains xattr names only related to LSMs which are enabled in the kernel configuration. However, EVM portable signatures do not depend on local information and a vendor might include in the signature calculation xattrs that are not enabled in the target platform.
Just including all xattrs names in evm_config_default_xattrnames is not a safe approach, because a target system might have already calculated signatures or HMACs based only on the enabled xattrs. After applying this patch, EVM would verify those signatures and HMACs with all xattrs instead. The non-enabled ones, which could possibly exist, would cause a verification error.
Thus, this patch adds a new field named enabled to the xattr_list structure, which is set to true if the LSM associated to a given xattr name is enabled in the kernel configuration. The non-enabled xattrs are taken into account only in evm_calc_hmac_or_hash(), if the passed security.evm type is EVM_XATTR_PORTABLE_DIGSIG.
The new function evm_protected_xattr_if_enabled() has been defined so that IMA can include all protected xattrs and not only the enabled ones in the measurement list, if the new template fields xattrnames, xattrlengths or xattrvalues have been included in the template format.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
c7c7a1a1 |
| 21-Jan-2021 |
Tycho Andersen <tycho@tycho.pizza> |
xattr: handle idmapped mounts
When interacting with extended attributes the vfs verifies that the caller is privileged over the inode with which the extended attribute is associated. For posix acces
xattr: handle idmapped mounts
When interacting with extended attributes the vfs verifies that the caller is privileged over the inode with which the extended attribute is associated. For posix access and posix default extended attributes a uid or gid can be stored on-disk. Let the functions handle posix extended attributes on idmapped mounts. If the inode is accessed through an idmapped mount we need to map it according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. This has no effect for e.g. security xattrs since they don't store uids or gids and don't perform permission checks on them like posix acls do.
Link: https://lore.kernel.org/r/20210121131959.646623-10-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Tycho Andersen <tycho@tycho.pizza> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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|
#
ccf11dba |
| 10-Jan-2021 |
Dinghao Liu <dinghao.liu@zju.edu.cn> |
evm: Fix memleak in init_desc
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 sha
evm: Fix memleak in init_desc
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 <dinghao.liu@zju.edu.cn> [zohar@linux.ibm.com: formatted/reworded patch description] Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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|
#
84338569 |
| 12-May-2020 |
Dan Carpenter <dan.carpenter@oracle.com> |
evm: Fix a small race in init_desc()
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 NUL
evm: Fix a small race in init_desc()
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 <roberto.sassu@huawei.com> Fixes: 53de3b080d5e ("evm: Check also if *tfm is an error pointer in init_desc()") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Roberto Sassu <roberto.sassu@huawei.com> Acked-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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|
#
0c4395fb |
| 14-Apr-2020 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Fix possible memory leak in evm_calc_hmac_or_hash()
Don't immediately return if the signature is portable and security.ima is not present. Just set error so that memory allocated is freed befor
evm: Fix possible memory leak in evm_calc_hmac_or_hash()
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 <roberto.sassu@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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|
#
770f6058 |
| 30-Apr-2020 |
Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> |
evm: Fix RCU list related warnings
This patch fixes the following warning and few other instances of traversal of evm_config_xattrnames list:
[ 32.848432] ============================= [ 32.848
evm: Fix RCU list related warnings
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 <lkp@intel.com> Suggested-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> (RCU viewpoint) Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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|
#
53de3b08 |
| 27-Apr-2020 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Check also if *tfm is an error pointer in init_desc()
This patch avoids a kernel panic due to accessing an error pointer set by crypto_alloc_shash(). It occurs especially when there are many fi
evm: Check also if *tfm is an error pointer in init_desc()
This patch avoids a kernel panic due to accessing an error pointer set by crypto_alloc_shash(). It occurs especially when there are many files that require an unsupported algorithm, as it would increase the likelihood of the following race condition:
Task A: *tfm = crypto_alloc_shash() <= error pointer Task B: if (*tfm == NULL) <= *tfm is not NULL, use it Task B: rc = crypto_shash_init(desc) <= panic Task A: *tfm = NULL
This patch uses the IS_ERR_OR_NULL macro to determine whether or not a new crypto context must be created.
Cc: stable@vger.kernel.org Fixes: d46eb3699502b ("evm: crypto hash replaced by shash") Co-developed-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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|
#
555d6d71 |
| 19-Feb-2020 |
Tushar Sugandhi <tusharsu@linux.microsoft.com> |
integrity: Remove duplicate pr_fmt definitions
The #define for formatting log messages, pr_fmt, is duplicated in the files under security/integrity.
This change moves the definition to security/int
integrity: Remove duplicate pr_fmt definitions
The #define for formatting log messages, pr_fmt, is duplicated in the files under security/integrity.
This change moves the definition to security/integrity/integrity.h and removes the duplicate definitions in the other files under security/integrity.
With this change, the messages in the following files will be prefixed with 'integrity'.
security/integrity/platform_certs/platform_keyring.c security/integrity/platform_certs/load_powerpc.c security/integrity/platform_certs/load_uefi.c security/integrity/iint.c
e.g. "integrity: Error adding keys to platform keyring %s\n"
And the messages in the following file will be prefixed with 'ima'.
security/integrity/ima/ima_mok.c
e.g. "ima: Allocating IMA blacklist keyring.\n"
For the rest of the files under security/integrity, there will be no change in the message format.
Suggested-by: Shuah Khan <skhan@linuxfoundation.org> Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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|
#
028db3e2 |
| 11-Jul-2019 |
Linus Torvalds <torvalds@linux-foundation.org> |
Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"
This reverts merge 0f75ef6a9cff49ff612f7ce0578bced9d0b38325 (and thus effectively commits
Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"
This reverts merge 0f75ef6a9cff49ff612f7ce0578bced9d0b38325 (and thus effectively commits
7a1ade847596 ("keys: Provide KEYCTL_GRANT_PERMISSION") 2e12256b9a76 ("keys: Replace uid/gid/perm permissions checking with an ACL")
that the merge brought in).
It turns out that it breaks booting with an encrypted volume, and Eric biggers reports that it also breaks the fscrypt tests [1] and loading of in-kernel X.509 certificates [2].
The root cause of all the breakage is likely the same, but David Howells is off email so rather than try to work it out it's getting reverted in order to not impact the rest of the merge window.
[1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/ [2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/
Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/ Reported-by: Eric Biggers <ebiggers@kernel.org> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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2e12256b |
| 27-Jun-2019 |
David Howells <dhowells@redhat.com> |
keys: Replace uid/gid/perm permissions checking with an ACL
Replace the uid/gid/perm permissions checking on a key with an ACL to allow the SETATTR and SEARCH permissions to be split. This will als
keys: Replace uid/gid/perm permissions checking with an ACL
Replace the uid/gid/perm permissions checking on a key with an ACL to allow the SETATTR and SEARCH permissions to be split. This will also allow a greater range of subjects to represented.
============ WHY DO THIS? ============
The problem is that SETATTR and SEARCH cover a slew of actions, not all of which should be grouped together.
For SETATTR, this includes actions that are about controlling access to a key:
(1) Changing a key's ownership.
(2) Changing a key's security information.
(3) Setting a keyring's restriction.
And actions that are about managing a key's lifetime:
(4) Setting an expiry time.
(5) Revoking a key.
and (proposed) managing a key as part of a cache:
(6) Invalidating a key.
Managing a key's lifetime doesn't really have anything to do with controlling access to that key.
Expiry time is awkward since it's more about the lifetime of the content and so, in some ways goes better with WRITE permission. It can, however, be set unconditionally by a process with an appropriate authorisation token for instantiating a key, and can also be set by the key type driver when a key is instantiated, so lumping it with the access-controlling actions is probably okay.
As for SEARCH permission, that currently covers:
(1) Finding keys in a keyring tree during a search.
(2) Permitting keyrings to be joined.
(3) Invalidation.
But these don't really belong together either, since these actions really need to be controlled separately.
Finally, there are number of special cases to do with granting the administrator special rights to invalidate or clear keys that I would like to handle with the ACL rather than key flags and special checks.
=============== WHAT IS CHANGED ===============
The SETATTR permission is split to create two new permissions:
(1) SET_SECURITY - which allows the key's owner, group and ACL to be changed and a restriction to be placed on a keyring.
(2) REVOKE - which allows a key to be revoked.
The SEARCH permission is split to create:
(1) SEARCH - which allows a keyring to be search and a key to be found.
(2) JOIN - which allows a keyring to be joined as a session keyring.
(3) INVAL - which allows a key to be invalidated.
The WRITE permission is also split to create:
(1) WRITE - which allows a key's content to be altered and links to be added, removed and replaced in a keyring.
(2) CLEAR - which allows a keyring to be cleared completely. This is split out to make it possible to give just this to an administrator.
(3) REVOKE - see above.
Keys acquire ACLs which consist of a series of ACEs, and all that apply are unioned together. An ACE specifies a subject, such as:
(*) Possessor - permitted to anyone who 'possesses' a key (*) Owner - permitted to the key owner (*) Group - permitted to the key group (*) Everyone - permitted to everyone
Note that 'Other' has been replaced with 'Everyone' on the assumption that you wouldn't grant a permit to 'Other' that you wouldn't also grant to everyone else.
Further subjects may be made available by later patches.
The ACE also specifies a permissions mask. The set of permissions is now:
VIEW Can view the key metadata READ Can read the key content WRITE Can update/modify the key content SEARCH Can find the key by searching/requesting LINK Can make a link to the key SET_SECURITY Can change owner, ACL, expiry INVAL Can invalidate REVOKE Can revoke JOIN Can join this keyring CLEAR Can clear this keyring
The KEYCTL_SETPERM function is then deprecated.
The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set, or if the caller has a valid instantiation auth token.
The KEYCTL_INVALIDATE function then requires INVAL.
The KEYCTL_REVOKE function then requires REVOKE.
The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an existing keyring.
The JOIN permission is enabled by default for session keyrings and manually created keyrings only.
====================== BACKWARD COMPATIBILITY ======================
To maintain backward compatibility, KEYCTL_SETPERM will translate the permissions mask it is given into a new ACL for a key - unless KEYCTL_SET_ACL has been called on that key, in which case an error will be returned.
It will convert possessor, owner, group and other permissions into separate ACEs, if each portion of the mask is non-zero.
SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned on if a keyring is being altered.
The KEYCTL_DESCRIBE function translates the ACL back into a permissions mask to return depending on possessor, owner, group and everyone ACEs.
It will make the following mappings:
(1) INVAL, JOIN -> SEARCH
(2) SET_SECURITY -> SETATTR
(3) REVOKE -> WRITE if SETATTR isn't already set
(4) CLEAR -> WRITE
Note that the value subsequently returned by KEYCTL_DESCRIBE may not match the value set with KEYCTL_SETATTR.
======= TESTING =======
This passes the keyutils testsuite for all but a couple of tests:
(1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed if the type doesn't have ->read(). You still can't actually read the key.
(2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't work as Other has been replaced with Everyone in the ACL.
Signed-off-by: David Howells <dhowells@redhat.com>
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b886d83c |
| 01-Jun-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify it under the terms of th
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation version 2 of the license
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 315 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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221be106 |
| 29-May-2019 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: check hash algorithm passed to init_desc()
This patch prevents memory access beyond the evm_tfm array by checking the validity of the index (hash algorithm) passed to init_desc(). The hash algo
evm: check hash algorithm passed to init_desc()
This patch prevents memory access beyond the evm_tfm array by checking the validity of the index (hash algorithm) passed to init_desc(). The hash algorithm can be arbitrarily set if the security.ima xattr type is not EVM_XATTR_HMAC.
Fixes: 5feeb61183dde ("evm: Allow non-SHA1 digital signatures") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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