diff options
| author | Mimi Zohar <zohar@linux.ibm.com> | 2023-12-12 06:12:43 -0500 |
|---|---|---|
| committer | Mimi Zohar <zohar@linux.ibm.com> | 2023-12-20 07:39:52 -0500 |
| commit | 40ca4ee3136d2d09977d1cab8c0c0e1582c3359d (patch) | |
| tree | 552c49da9983f04c064d62e019fff50ddcd37d6f /security | |
| parent | 4e8daa792742635ea57c625098165eef64661901 (diff) | |
| download | lwn-40ca4ee3136d2d09977d1cab8c0c0e1582c3359d.tar.gz lwn-40ca4ee3136d2d09977d1cab8c0c0e1582c3359d.zip | |
evm: don't copy up 'security.evm' xattr
The security.evm HMAC and the original file signatures contain
filesystem specific data. As a result, the HMAC and signature
are not the same on the stacked and backing filesystems.
Don't copy up 'security.evm'.
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Diffstat (limited to 'security')
| -rw-r--r-- | security/integrity/evm/evm_main.c | 7 | ||||
| -rw-r--r-- | security/security.c | 2 |
2 files changed, 8 insertions, 1 deletions
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 894570fe39bc..02adba635b02 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -863,6 +863,13 @@ void evm_inode_post_setattr(struct dentry *dentry, int ia_valid) evm_update_evmxattr(dentry, NULL, NULL, 0); } +int evm_inode_copy_up_xattr(const char *name) +{ + if (strcmp(name, XATTR_NAME_EVM) == 0) + return 1; /* Discard */ + return -EOPNOTSUPP; +} + /* * evm_inode_init_security - initializes security.evm HMAC value */ diff --git a/security/security.c b/security/security.c index dcb3e7014f9b..f00ec4d988b8 100644 --- a/security/security.c +++ b/security/security.c @@ -2539,7 +2539,7 @@ int security_inode_copy_up_xattr(const char *name) return rc; } - return LSM_RET_DEFAULT(inode_copy_up_xattr); + return evm_inode_copy_up_xattr(name); } EXPORT_SYMBOL(security_inode_copy_up_xattr); |