diff options
author | Otavio Salvador <otavio@ossystems.com.br> | 2018-12-12 11:20:31 -0200 |
---|---|---|
committer | GitHub <noreply@github.com> | 2018-12-12 11:20:31 -0200 |
commit | 1e71d8c630cbc0d1f5d762fd019690b5cdb880ae (patch) | |
tree | 58b4b37bed385b27fc5956435b2451c760f26f5f /security | |
parent | 5f3fecbc0715a70437501e1d85e74726c4f561be (diff) | |
parent | cfbbc7703fff59c67761c93a8b1de29a79f9841c (diff) |
Merge pull request #40 from toradex/4.9-2.3.x-imx
4.9 2.3.x imx
Diffstat (limited to 'security')
-rw-r--r-- | security/integrity/evm/evm.h | 2 | ||||
-rw-r--r-- | security/integrity/evm/evm_crypto.c | 87 | ||||
-rw-r--r-- | security/integrity/evm/evm_main.c | 29 | ||||
-rw-r--r-- | security/integrity/iint.c | 3 | ||||
-rw-r--r-- | security/integrity/ima/ima_api.c | 67 | ||||
-rw-r--r-- | security/integrity/ima/ima_appraise.c | 31 | ||||
-rw-r--r-- | security/integrity/ima/ima_crypto.c | 10 | ||||
-rw-r--r-- | security/integrity/ima/ima_fs.c | 6 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 77 | ||||
-rw-r--r-- | security/integrity/integrity.h | 18 | ||||
-rw-r--r-- | security/selinux/ss/policydb.c | 2 |
11 files changed, 237 insertions, 95 deletions
diff --git a/security/integrity/evm/evm.h b/security/integrity/evm/evm.h index f5f12727771a..2ff02459fcfd 100644 --- a/security/integrity/evm/evm.h +++ b/security/integrity/evm/evm.h @@ -48,7 +48,7 @@ int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name, size_t req_xattr_value_len, char *digest); int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name, const char *req_xattr_value, - size_t req_xattr_value_len, char *digest); + size_t req_xattr_value_len, char type, char *digest); int evm_init_hmac(struct inode *inode, const struct xattr *xattr, char *hmac_val); int evm_init_secfs(void); diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c index 6fcbd8e99baf..c783fefa558a 100644 --- a/security/integrity/evm/evm_crypto.c +++ b/security/integrity/evm/evm_crypto.c @@ -139,7 +139,7 @@ out: * protection.) */ static void hmac_add_misc(struct shash_desc *desc, struct inode *inode, - char *digest) + char type, char *digest) { struct h_misc { unsigned long ino; @@ -150,13 +150,27 @@ static void hmac_add_misc(struct shash_desc *desc, struct inode *inode, } hmac_misc; memset(&hmac_misc, 0, sizeof(hmac_misc)); - hmac_misc.ino = inode->i_ino; - hmac_misc.generation = inode->i_generation; - hmac_misc.uid = from_kuid(inode->i_sb->s_user_ns, inode->i_uid); - hmac_misc.gid = from_kgid(inode->i_sb->s_user_ns, inode->i_gid); + /* Don't include the inode or generation number in portable + * signatures + */ + if (type != EVM_XATTR_PORTABLE_DIGSIG) { + hmac_misc.ino = inode->i_ino; + hmac_misc.generation = inode->i_generation; + } + /* The hmac uid and gid must be encoded in the initial user + * namespace (not the filesystems user namespace) as encoding + * them in the filesystems user namespace allows an attack + * where first they are written in an unprivileged fuse mount + * of a filesystem and then the system is tricked to mount the + * filesystem for real on next boot and trust it because + * everything is signed. + */ + hmac_misc.uid = from_kuid(&init_user_ns, inode->i_uid); + hmac_misc.gid = from_kgid(&init_user_ns, inode->i_gid); hmac_misc.mode = inode->i_mode; crypto_shash_update(desc, (const u8 *)&hmac_misc, sizeof(hmac_misc)); - if (evm_hmac_attrs & EVM_ATTR_FSUUID) + if ((evm_hmac_attrs & EVM_ATTR_FSUUID) && + type != EVM_XATTR_PORTABLE_DIGSIG) crypto_shash_update(desc, inode->i_sb->s_uuid, sizeof(inode->i_sb->s_uuid)); crypto_shash_final(desc, digest); @@ -182,6 +196,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry, char *xattr_value = NULL; int error; int size; + bool ima_present = false; if (!(inode->i_opflags & IOP_XATTR)) return -EOPNOTSUPP; @@ -192,11 +207,18 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry, error = -ENODATA; for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) { + bool is_ima = false; + + if (strcmp(*xattrname, XATTR_NAME_IMA) == 0) + is_ima = true; + if ((req_xattr_name && req_xattr_value) && !strcmp(*xattrname, req_xattr_name)) { error = 0; crypto_shash_update(desc, (const u8 *)req_xattr_value, req_xattr_value_len); + if (is_ima) + ima_present = true; continue; } size = vfs_getxattr_alloc(dentry, *xattrname, @@ -211,9 +233,14 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry, error = 0; xattr_size = size; crypto_shash_update(desc, (const u8 *)xattr_value, xattr_size); + if (is_ima) + ima_present = true; } - hmac_add_misc(desc, inode, digest); + hmac_add_misc(desc, inode, type, digest); + /* Portable EVM signatures must include an IMA hash */ + if (type == EVM_XATTR_PORTABLE_DIGSIG && !ima_present) + return -EPERM; out: kfree(xattr_value); kfree(desc); @@ -225,17 +252,45 @@ int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name, char *digest) { return evm_calc_hmac_or_hash(dentry, req_xattr_name, req_xattr_value, - req_xattr_value_len, EVM_XATTR_HMAC, digest); + req_xattr_value_len, EVM_XATTR_HMAC, digest); } int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name, const char *req_xattr_value, size_t req_xattr_value_len, - char *digest) + char type, char *digest) { return evm_calc_hmac_or_hash(dentry, req_xattr_name, req_xattr_value, - req_xattr_value_len, IMA_XATTR_DIGEST, digest); + req_xattr_value_len, type, digest); +} + +static int evm_is_immutable(struct dentry *dentry, struct inode *inode) +{ + const struct evm_ima_xattr_data *xattr_data = NULL; + struct integrity_iint_cache *iint; + int rc = 0; + + iint = integrity_iint_find(inode); + if (iint && (iint->flags & EVM_IMMUTABLE_DIGSIG)) + return 1; + + /* Do this the hard way */ + rc = vfs_getxattr_alloc(dentry, XATTR_NAME_EVM, (char **)&xattr_data, 0, + GFP_NOFS); + if (rc <= 0) { + if (rc == -ENODATA) + return 0; + return rc; + } + if (xattr_data->type == EVM_XATTR_PORTABLE_DIGSIG) + rc = 1; + else + rc = 0; + + kfree(xattr_data); + return rc; } + /* * Calculate the hmac and update security.evm xattr * @@ -248,6 +303,16 @@ int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name, struct evm_ima_xattr_data xattr_data; int rc = 0; + /* + * Don't permit any transformation of the EVM xattr if the signature + * is of an immutable type + */ + rc = evm_is_immutable(dentry, inode); + if (rc < 0) + return rc; + if (rc) + return -EPERM; + rc = evm_calc_hmac(dentry, xattr_name, xattr_value, xattr_value_len, xattr_data.digest); if (rc == 0) { @@ -273,7 +338,7 @@ int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr, } crypto_shash_update(desc, lsm_xattr->value, lsm_xattr->value_len); - hmac_add_misc(desc, inode, hmac_val); + hmac_add_misc(desc, inode, EVM_XATTR_HMAC, hmac_val); kfree(desc); return 0; } diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index ba8615576d4d..976b8dce6496 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -29,7 +29,7 @@ int evm_initialized; static char *integrity_status_msg[] = { - "pass", "fail", "no_label", "no_xattrs", "unknown" + "pass", "pass_immutable", "fail", "no_label", "no_xattrs", "unknown" }; char *evm_hmac = "hmac(sha1)"; char *evm_hash = "sha1"; @@ -118,7 +118,8 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, enum integrity_status evm_status = INTEGRITY_PASS; int rc, xattr_len; - if (iint && iint->evm_status == INTEGRITY_PASS) + if (iint && (iint->evm_status == INTEGRITY_PASS || + iint->evm_status == INTEGRITY_PASS_IMMUTABLE)) return iint->evm_status; /* if status is not PASS, try to check again - against -ENOMEM */ @@ -155,22 +156,26 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, rc = -EINVAL; break; case EVM_IMA_XATTR_DIGSIG: + case EVM_XATTR_PORTABLE_DIGSIG: rc = evm_calc_hash(dentry, xattr_name, xattr_value, - xattr_value_len, calc.digest); + xattr_value_len, xattr_data->type, + calc.digest); if (rc) break; rc = integrity_digsig_verify(INTEGRITY_KEYRING_EVM, (const char *)xattr_data, xattr_len, calc.digest, sizeof(calc.digest)); if (!rc) { - /* Replace RSA with HMAC if not mounted readonly and - * not immutable - */ - if (!IS_RDONLY(d_backing_inode(dentry)) && - !IS_IMMUTABLE(d_backing_inode(dentry))) + if (xattr_data->type == EVM_XATTR_PORTABLE_DIGSIG) { + if (iint) + iint->flags |= EVM_IMMUTABLE_DIGSIG; + evm_status = INTEGRITY_PASS_IMMUTABLE; + } else if (!IS_RDONLY(d_backing_inode(dentry)) && + !IS_IMMUTABLE(d_backing_inode(dentry))) { evm_update_evmxattr(dentry, xattr_name, xattr_value, xattr_value_len); + } } break; default: @@ -271,7 +276,7 @@ static enum integrity_status evm_verify_current_integrity(struct dentry *dentry) * affect security.evm. An interesting side affect of writing posix xattr * acls is their modifying of the i_mode, which is included in security.evm. * For posix xattr acls only, permit security.evm, even if it currently - * doesn't exist, to be updated. + * doesn't exist, to be updated unless the EVM signature is immutable. */ static int evm_protect_xattr(struct dentry *dentry, const char *xattr_name, const void *xattr_value, size_t xattr_value_len) @@ -339,7 +344,8 @@ int evm_inode_setxattr(struct dentry *dentry, const char *xattr_name, if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) { if (!xattr_value_len) return -EINVAL; - if (xattr_data->type != EVM_IMA_XATTR_DIGSIG) + if (xattr_data->type != EVM_IMA_XATTR_DIGSIG && + xattr_data->type != EVM_XATTR_PORTABLE_DIGSIG) return -EPERM; } return evm_protect_xattr(dentry, xattr_name, xattr_value, @@ -416,6 +422,9 @@ void evm_inode_post_removexattr(struct dentry *dentry, const char *xattr_name) /** * evm_inode_setattr - prevent updating an invalid EVM extended attribute * @dentry: pointer to the affected dentry + * + * Permit update of file attributes when files have a valid EVM signature, + * except in the case of them having an immutable portable signature. */ int evm_inode_setattr(struct dentry *dentry, struct iattr *attr) { diff --git a/security/integrity/iint.c b/security/integrity/iint.c index c710d22042f9..7ea39b19e8ad 100644 --- a/security/integrity/iint.c +++ b/security/integrity/iint.c @@ -74,6 +74,7 @@ static void iint_free(struct integrity_iint_cache *iint) iint->ima_hash = NULL; iint->version = 0; iint->flags = 0UL; + iint->atomic_flags = 0UL; iint->ima_file_status = INTEGRITY_UNKNOWN; iint->ima_mmap_status = INTEGRITY_UNKNOWN; iint->ima_bprm_status = INTEGRITY_UNKNOWN; @@ -155,12 +156,14 @@ static void init_once(void *foo) memset(iint, 0, sizeof(*iint)); iint->version = 0; iint->flags = 0UL; + iint->atomic_flags = 0; iint->ima_file_status = INTEGRITY_UNKNOWN; iint->ima_mmap_status = INTEGRITY_UNKNOWN; iint->ima_bprm_status = INTEGRITY_UNKNOWN; iint->ima_read_status = INTEGRITY_UNKNOWN; iint->evm_status = INTEGRITY_UNKNOWN; iint->measured_pcrs = 0; + mutex_init(&iint->mutex); } static int __init integrity_iintcache_init(void) diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index d01a52f8f708..3b43057bf949 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -198,42 +198,59 @@ int ima_collect_measurement(struct integrity_iint_cache *iint, struct inode *inode = file_inode(file); const char *filename = file->f_path.dentry->d_name.name; int result = 0; + int length; + void *tmpbuf; + u64 i_version; struct { struct ima_digest_data hdr; char digest[IMA_MAX_DIGEST_SIZE]; } hash; - if (!(iint->flags & IMA_COLLECTED)) { - u64 i_version = file_inode(file)->i_version; + if (iint->flags & IMA_COLLECTED) + goto out; - if (file->f_flags & O_DIRECT) { - audit_cause = "failed(directio)"; - result = -EACCES; - goto out; - } + /* + * Dectecting file change is based on i_version. On filesystems + * which do not support i_version, support is limited to an initial + * measurement/appraisal/audit. + */ + i_version = file_inode(file)->i_version; + hash.hdr.algo = algo; - hash.hdr.algo = algo; - - result = (!buf) ? ima_calc_file_hash(file, &hash.hdr) : - ima_calc_buffer_hash(buf, size, &hash.hdr); - if (!result) { - int length = sizeof(hash.hdr) + hash.hdr.length; - void *tmpbuf = krealloc(iint->ima_hash, length, - GFP_NOFS); - if (tmpbuf) { - iint->ima_hash = tmpbuf; - memcpy(iint->ima_hash, &hash, length); - iint->version = i_version; - iint->flags |= IMA_COLLECTED; - } else - result = -ENOMEM; - } + /* Initialize hash digest to 0's in case of failure */ + memset(&hash.digest, 0, sizeof(hash.digest)); + + if (buf) + result = ima_calc_buffer_hash(buf, size, &hash.hdr); + else + result = ima_calc_file_hash(file, &hash.hdr); + + if (result && result != -EBADF && result != -EINVAL) + goto out; + + length = sizeof(hash.hdr) + hash.hdr.length; + tmpbuf = krealloc(iint->ima_hash, length, GFP_NOFS); + if (!tmpbuf) { + result = -ENOMEM; + goto out; } + + iint->ima_hash = tmpbuf; + memcpy(iint->ima_hash, &hash, length); + iint->version = i_version; + + /* Possibly temporary failure due to type of read (eg. O_DIRECT) */ + if (!result) + iint->flags |= IMA_COLLECTED; out: - if (result) + if (result) { + if (file->f_flags & O_DIRECT) + audit_cause = "failed(directio)"; + integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, filename, "collect_data", audit_cause, result, 0); + } return result; } @@ -277,7 +294,7 @@ void ima_store_measurement(struct integrity_iint_cache *iint, } result = ima_store_template(entry, violation, inode, filename, pcr); - if (!result || result == -EEXIST) { + if ((!result || result == -EEXIST) && !(file->f_flags & O_DIRECT)) { iint->flags |= IMA_MEASURED; iint->measured_pcrs |= (0x1 << pcr); } diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 1e6f23f77f15..af55c31754a4 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -214,7 +214,9 @@ int ima_appraise_measurement(enum ima_hooks func, } status = evm_verifyxattr(dentry, XATTR_NAME_IMA, xattr_value, rc, iint); - if ((status != INTEGRITY_PASS) && (status != INTEGRITY_UNKNOWN)) { + if ((status != INTEGRITY_PASS) && + (status != INTEGRITY_PASS_IMMUTABLE) && + (status != INTEGRITY_UNKNOWN)) { if ((status == INTEGRITY_NOLABEL) || (status == INTEGRITY_NOXATTRS)) cause = "missing-HMAC"; @@ -232,6 +234,7 @@ int ima_appraise_measurement(enum ima_hooks func, status = INTEGRITY_FAIL; break; } + clear_bit(IMA_DIGSIG, &iint->atomic_flags); if (xattr_len - sizeof(xattr_value->type) - hash_start >= iint->ima_hash->length) /* xattr length may be longer. md5 hash in previous @@ -250,7 +253,7 @@ int ima_appraise_measurement(enum ima_hooks func, status = INTEGRITY_PASS; break; case EVM_IMA_XATTR_DIGSIG: - iint->flags |= IMA_DIGSIG; + set_bit(IMA_DIGSIG, &iint->atomic_flags); rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA, (const char *)xattr_value, rc, iint->ima_hash->digest, @@ -301,7 +304,7 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file) int rc = 0; /* do not collect and update hash for digital signatures */ - if (iint->flags & IMA_DIGSIG) + if (test_bit(IMA_DIGSIG, &iint->atomic_flags)) return; if (iint->ima_file_status != INTEGRITY_PASS) @@ -311,7 +314,9 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file) if (rc < 0) return; + inode_lock(file_inode(file)); ima_fix_xattr(dentry, iint); + inode_unlock(file_inode(file)); } /** @@ -334,16 +339,14 @@ void ima_inode_post_setattr(struct dentry *dentry) return; must_appraise = ima_must_appraise(inode, MAY_ACCESS, POST_SETATTR); + if (!must_appraise) + __vfs_removexattr(dentry, XATTR_NAME_IMA); iint = integrity_iint_find(inode); if (iint) { - iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED | - IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK | - IMA_ACTION_RULE_FLAGS); - if (must_appraise) - iint->flags |= IMA_APPRAISE; + set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags); + if (!must_appraise) + clear_bit(IMA_UPDATE_XATTR, &iint->atomic_flags); } - if (!must_appraise) - __vfs_removexattr(dentry, XATTR_NAME_IMA); } /* @@ -372,12 +375,12 @@ static void ima_reset_appraise_flags(struct inode *inode, int digsig) iint = integrity_iint_find(inode); if (!iint) return; - - iint->flags &= ~IMA_DONE_MASK; iint->measured_pcrs = 0; + set_bit(IMA_CHANGE_XATTR, &iint->atomic_flags); if (digsig) - iint->flags |= IMA_DIGSIG; - return; + set_bit(IMA_DIGSIG, &iint->atomic_flags); + else + clear_bit(IMA_DIGSIG, &iint->atomic_flags); } int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name, diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 93f09173cc49..20e66291ca99 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -443,6 +443,16 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) loff_t i_size; int rc; + /* + * For consistency, fail file's opened with the O_DIRECT flag on + * filesystems mounted with/without DAX option. + */ + if (file->f_flags & O_DIRECT) { + hash->length = hash_digest_size[ima_hash_algo]; + hash->algo = ima_hash_algo; + return -EINVAL; + } + i_size = i_size_read(file_inode(file)); if (ima_ahash_minsize && i_size >= ima_ahash_minsize) { diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 3df46906492d..44b44d7e0dbc 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -29,14 +29,14 @@ static DEFINE_MUTEX(ima_write_mutex); static int valid_policy = 1; -#define TMPBUFLEN 12 + static ssize_t ima_show_htable_value(char __user *buf, size_t count, loff_t *ppos, atomic_long_t *val) { - char tmpbuf[TMPBUFLEN]; + char tmpbuf[32]; /* greater than largest 'long' string value */ ssize_t len; - len = scnprintf(tmpbuf, TMPBUFLEN, "%li\n", atomic_long_read(val)); + len = scnprintf(tmpbuf, sizeof(tmpbuf), "%li\n", atomic_long_read(val)); return simple_read_from_buffer(buf, count, ppos, tmpbuf, len); } diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 9652541c4d43..ea1e629a5d4c 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -99,10 +99,13 @@ static void ima_rdwr_violation_check(struct file *file, if (!iint) iint = integrity_iint_find(inode); /* IMA_MEASURE is set from reader side */ - if (iint && (iint->flags & IMA_MEASURE)) + if (iint && test_bit(IMA_MUST_MEASURE, + &iint->atomic_flags)) send_tomtou = true; } } else { + if (must_measure) + set_bit(IMA_MUST_MEASURE, &iint->atomic_flags); if ((atomic_read(&inode->i_writecount) > 0) && must_measure) send_writers = true; } @@ -124,21 +127,24 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint, struct inode *inode, struct file *file) { fmode_t mode = file->f_mode; + bool update; if (!(mode & FMODE_WRITE)) return; - inode_lock(inode); + mutex_lock(&iint->mutex); if (atomic_read(&inode->i_writecount) == 1) { + update = test_and_clear_bit(IMA_UPDATE_XATTR, + &iint->atomic_flags); if ((iint->version != inode->i_version) || (iint->flags & IMA_NEW_FILE)) { iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE); iint->measured_pcrs = 0; - if (iint->flags & IMA_APPRAISE) + if (update) ima_update_xattr(iint, file); } } - inode_unlock(inode); + mutex_unlock(&iint->mutex); } /** @@ -171,7 +177,7 @@ static int process_measurement(struct file *file, char *buf, loff_t size, char *pathbuf = NULL; char filename[NAME_MAX]; const char *pathname = NULL; - int rc = -ENOMEM, action, must_appraise; + int rc = 0, action, must_appraise = 0; int pcr = CONFIG_IMA_MEASURE_PCR_IDX; struct evm_ima_xattr_data *xattr_value = NULL; int xattr_len = 0; @@ -202,17 +208,31 @@ static int process_measurement(struct file *file, char *buf, loff_t size, if (action) { iint = integrity_inode_get(inode); if (!iint) - goto out; + rc = -ENOMEM; } - if (violation_check) { + if (!rc && violation_check) ima_rdwr_violation_check(file, iint, action & IMA_MEASURE, &pathbuf, &pathname); - if (!action) { - rc = 0; - goto out_free; - } - } + + inode_unlock(inode); + + if (rc) + goto out; + if (!action) + goto out; + + mutex_lock(&iint->mutex); + + if (test_and_clear_bit(IMA_CHANGE_ATTR, &iint->atomic_flags)) + /* reset appraisal flags if ima_inode_post_setattr was called */ + iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED | + IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK | + IMA_ACTION_FLAGS); + + if (test_and_clear_bit(IMA_CHANGE_XATTR, &iint->atomic_flags)) + /* reset all flags if ima_inode_setxattr was called */ + iint->flags &= ~IMA_DONE_MASK; /* Determine if already appraised/measured based on bitmask * (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED, @@ -230,7 +250,7 @@ static int process_measurement(struct file *file, char *buf, loff_t size, if (!action) { if (must_appraise) rc = ima_get_cache_status(iint, func); - goto out_digsig; + goto out_locked; } template_desc = ima_template_desc_current(); @@ -242,11 +262,8 @@ static int process_measurement(struct file *file, char *buf, loff_t size, hash_algo = ima_get_hash_algo(xattr_value, xattr_len); rc = ima_collect_measurement(iint, file, buf, size, hash_algo); - if (rc != 0) { - if (file->f_flags & O_DIRECT) - rc = (iint->flags & IMA_PERMIT_DIRECTIO) ? 0 : -EACCES; - goto out_digsig; - } + if (rc != 0 && rc != -EBADF && rc != -EINVAL) + goto out_locked; if (!pathbuf) /* ima_rdwr_violation possibly pre-fetched */ pathname = ima_d_path(&file->f_path, &pathbuf, filename); @@ -254,24 +271,32 @@ static int process_measurement(struct file *file, char *buf, loff_t size, if (action & IMA_MEASURE) ima_store_measurement(iint, file, pathname, xattr_value, xattr_len, pcr); - if (action & IMA_APPRAISE_SUBMASK) + if (rc == 0 && (action & IMA_APPRAISE_SUBMASK)) { + inode_lock(inode); rc = ima_appraise_measurement(func, iint, file, pathname, xattr_value, xattr_len, opened); + inode_unlock(inode); + } if (action & IMA_AUDIT) ima_audit_measurement(iint, pathname); -out_digsig: - if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG) && + if ((file->f_flags & O_DIRECT) && (iint->flags & IMA_PERMIT_DIRECTIO)) + rc = 0; +out_locked: + if ((mask & MAY_WRITE) && test_bit(IMA_DIGSIG, &iint->atomic_flags) && !(iint->flags & IMA_NEW_FILE)) rc = -EACCES; + mutex_unlock(&iint->mutex); kfree(xattr_value); -out_free: +out: if (pathbuf) __putname(pathbuf); -out: - inode_unlock(inode); - if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE)) - return -EACCES; + if (must_appraise) { + if (rc && (ima_appraise & IMA_APPRAISE_ENFORCE)) + return -EACCES; + if (file->f_mode & FMODE_WRITE) + set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags); + } return 0; } diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 24520b4ef3b0..2f7e236b931c 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -29,10 +29,10 @@ /* iint cache flags */ #define IMA_ACTION_FLAGS 0xff000000 #define IMA_ACTION_RULE_FLAGS 0x06000000 -#define IMA_DIGSIG 0x01000000 -#define IMA_DIGSIG_REQUIRED 0x02000000 -#define IMA_PERMIT_DIRECTIO 0x04000000 -#define IMA_NEW_FILE 0x08000000 +#define IMA_DIGSIG_REQUIRED 0x01000000 +#define IMA_PERMIT_DIRECTIO 0x02000000 +#define IMA_NEW_FILE 0x04000000 +#define EVM_IMMUTABLE_DIGSIG 0x08000000 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \ IMA_APPRAISE_SUBMASK) @@ -53,11 +53,19 @@ #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \ IMA_BPRM_APPRAISED | IMA_READ_APPRAISED) +/* iint cache atomic_flags */ +#define IMA_CHANGE_XATTR 0 +#define IMA_UPDATE_XATTR 1 +#define IMA_CHANGE_ATTR 2 +#define IMA_DIGSIG 3 +#define IMA_MUST_MEASURE 4 + enum evm_ima_xattr_type { IMA_XATTR_DIGEST = 0x01, EVM_XATTR_HMAC, EVM_IMA_XATTR_DIGSIG, IMA_XATTR_DIGEST_NG, + EVM_XATTR_PORTABLE_DIGSIG, IMA_XATTR_LAST }; @@ -100,10 +108,12 @@ struct signature_v2_hdr { /* integrity data associated with an inode */ struct integrity_iint_cache { struct rb_node rb_node; /* rooted in integrity_iint_tree */ + struct mutex mutex; /* protects: version, flags, digest */ struct inode *inode; /* back pointer to inode in question */ u64 version; /* track inode changes */ unsigned long flags; unsigned long measured_pcrs; + unsigned long atomic_flags; enum integrity_status ima_file_status:4; enum integrity_status ima_mmap_status:4; enum integrity_status ima_bprm_status:4; diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c index d719db4219cd..175e4dce58df 100644 --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -1097,7 +1097,7 @@ static int str_read(char **strp, gfp_t flags, void *fp, u32 len) if ((len == 0) || (len == (u32)-1)) return -EINVAL; - str = kmalloc(len + 1, flags); + str = kmalloc(len + 1, flags | __GFP_NOWARN); if (!str) return -ENOMEM; |