Merge tag 'integrity-v5.11' of git://git.kernel.org/pub/scm/linux/ker…

…nel/git/zohar/linux-integrity

Pull integrity subsystem updates from Mimi Zohar:
 "Just three patches here. Other integrity changes are being upstreamed
  via EFI (defines a common EFI secure and trusted boot IMA policy) and
  BPF LSM (exporting the IMA file cache hash info based on inode).

  The three patches included here:

   - bug fix: fail calculating the file hash, when a file not opened for
     read and the attempt to re-open it for read fails.

   - defer processing the "ima_appraise" boot command line option to
     avoid enabling different modes (e.g. fix, log) to when the secure
     boot flag is available on arm.

   - defines "ima-buf" as the default IMA buffer measurement template in
     preparation for the builtin integrity "critical data" policy"

* tag 'integrity-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  ima: Don't modify file descriptor mode on the fly
  ima: select ima-buf template for buffer measurement
  ima: defer arch_ima_get_secureboot() call to IMA init time

include/linux/ima.h

@@ -32,6 +32,12 @@ extern int ima_file_hash(struct file *file, char *buf, size_t buf_size);
 extern int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size);
 extern void ima_kexec_cmdline(int kernel_fd, const void *buf, int size);
 
+#ifdef CONFIG_IMA_APPRAISE_BOOTPARAM
+extern void ima_appraise_parse_cmdline(void);
+#else
+static inline void ima_appraise_parse_cmdline(void) {}
+#endif
+
 #ifdef CONFIG_IMA_KEXEC
 extern void ima_add_kexec_buffer(struct kimage *image);
 #endif

security/integrity/ima/ima.h

@@ -156,6 +156,7 @@ int template_desc_init_fields(const char *template_fmt,
 			      const struct ima_template_field ***fields,
 			      int *num_fields);
 struct ima_template_desc *ima_template_desc_current(void);
+struct ima_template_desc *ima_template_desc_buf(void);
 struct ima_template_desc *lookup_template_desc(const char *name);
 bool ima_template_has_modsig(const struct ima_template_desc *ima_template);
 int ima_restore_measurement_entry(struct ima_template_entry *entry);

security/integrity/ima/ima_appraise.c

@@ -5,6 +5,7 @@
  * Author:
  * Mimi Zohar <zohar@us.ibm.com>
  */
+#include <linux/module.h>
 #include <linux/init.h>
 #include <linux/file.h>
 #include <linux/fs.h>
@@ -16,12 +17,19 @@
 
 #include "ima.h"
 
-static int __init default_appraise_setup(char *str)
-{
 #ifdef CONFIG_IMA_APPRAISE_BOOTPARAM
+static char *ima_appraise_cmdline_default __initdata;
+core_param(ima_appraise, ima_appraise_cmdline_default, charp, 0);
+
+void __init ima_appraise_parse_cmdline(void)
+{
+	const char *str = ima_appraise_cmdline_default;
 	bool sb_state = arch_ima_get_secureboot();
 	int appraisal_state = ima_appraise;
 
+	if (!str)
+		return;
+
 	if (strncmp(str, "off", 3) == 0)
 		appraisal_state = 0;
 	else if (strncmp(str, "log", 3) == 0)
@@ -42,11 +50,8 @@ static int __init default_appraise_setup(char *str)
 	} else {
 		ima_appraise = appraisal_state;
 	}
-#endif
-	return 1;
 }
-
-__setup("ima_appraise=", default_appraise_setup);
+#endif
 
 /*
  * is_ima_appraise_enabled - return appraise status

security/integrity/ima/ima_crypto.c

@@ -537,7 +537,7 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash)
 	loff_t i_size;
 	int rc;
 	struct file *f = file;
-	bool new_file_instance = false, modified_mode = false;
+	bool new_file_instance = false;
 
 	/*
 	 * For consistency, fail file's opened with the O_DIRECT flag on
@@ -555,18 +555,10 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash)
 				O_TRUNC | O_CREAT | O_NOCTTY | O_EXCL);
 		flags |= O_RDONLY;
 		f = dentry_open(&file->f_path, flags, file->f_cred);
-		if (IS_ERR(f)) {
-			/*
-			 * Cannot open the file again, lets modify f_mode
-			 * of original and continue
-			 */
-			pr_info_ratelimited("Unable to reopen file for reading.\n");
-			f = file;
-			f->f_mode |= FMODE_READ;
-			modified_mode = true;
-		} else {
-			new_file_instance = true;
-		}
+		if (IS_ERR(f))
+			return PTR_ERR(f);
+
+		new_file_instance = true;
 	}
 
 	i_size = i_size_read(file_inode(f));
@@ -581,8 +573,6 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash)
 out:
 	if (new_file_instance)
 		fput(f);
-	else if (modified_mode)
-		f->f_mode &= ~FMODE_READ;
 	return rc;
 }
 

security/integrity/ima/ima_main.c

@@ -413,7 +413,7 @@ int ima_file_mmap(struct file *file, unsigned long prot)
  */
 int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
 {
-	struct ima_template_desc *template;
+	struct ima_template_desc *template = NULL;
 	struct file *file = vma->vm_file;
 	char filename[NAME_MAX];
 	char *pathbuf = NULL;
@@ -832,7 +832,7 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size,
 					    .filename = eventname,
 					    .buf = buf,
 					    .buf_len = size};
-	struct ima_template_desc *template = NULL;
+	struct ima_template_desc *template;
 	struct {
 		struct ima_digest_data hdr;
 		char digest[IMA_MAX_DIGEST_SIZE];
@@ -844,6 +844,13 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size,
 	if (!ima_policy_flag)
 		return;
 
+	template = ima_template_desc_buf();
+	if (!template) {
+		ret = -EINVAL;
+		audit_cause = "ima_template_desc_buf";
+		goto out;
+	}
+
 	/*
 	 * Both LSM hooks and auxilary based buffer measurements are
 	 * based on policy.  To avoid code duplication, differentiate
@@ -862,19 +869,6 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size,
 	if (!pcr)
 		pcr = CONFIG_IMA_MEASURE_PCR_IDX;
 
-	if (!template) {
-		template = lookup_template_desc("ima-buf");
-		ret = template_desc_init_fields(template->fmt,
-						&(template->fields),
-						&(template->num_fields));
-		if (ret < 0) {
-			pr_err("template %s init failed, result: %d\n",
-			       (strlen(template->name) ?
-				template->name : template->fmt), ret);
-			return;
-		}
-	}
-
 	iint.ima_hash = &hash.hdr;
 	iint.ima_hash->algo = ima_hash_algo;
 	iint.ima_hash->length = hash_digest_size[ima_hash_algo];
@@ -934,6 +928,7 @@ static int __init init_ima(void)
 {
 	int error;
 
+	ima_appraise_parse_cmdline();
 	ima_init_template_list();
 	hash_setup(CONFIG_IMA_DEFAULT_HASH);
 	error = ima_init();

security/integrity/ima/ima_policy.c

@@ -628,7 +628,7 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
 	struct ima_rule_entry *entry;
 	int action = 0, actmask = flags | (flags << 1);
 
-	if (template_desc)
+	if (template_desc && !*template_desc)
 		*template_desc = ima_template_desc_current();
 
 	rcu_read_lock();

security/integrity/ima/ima_template.c

@@ -55,6 +55,7 @@ static const struct ima_template_field supported_fields[] = {
 #define MAX_TEMPLATE_NAME_LEN sizeof("d-ng|n-ng|sig|buf|d-modisg|modsig")
 
 static struct ima_template_desc *ima_template;
+static struct ima_template_desc *ima_buf_template;
 
 /**
  * ima_template_has_modsig - Check whether template has modsig-related fields.
@@ -252,11 +253,36 @@ struct ima_template_desc *ima_template_desc_current(void)
 	return ima_template;
 }
 
+struct ima_template_desc *ima_template_desc_buf(void)
+{
+	if (!ima_buf_template) {
+		ima_init_template_list();
+		ima_buf_template = lookup_template_desc("ima-buf");
+	}
+	return ima_buf_template;
+}
+
 int __init ima_init_template(void)
 {
 	struct ima_template_desc *template = ima_template_desc_current();
 	int result;
 
+	result = template_desc_init_fields(template->fmt,
+					   &(template->fields),
+					   &(template->num_fields));
+	if (result < 0) {
+		pr_err("template %s init failed, result: %d\n",
+		       (strlen(template->name) ?
+		       template->name : template->fmt), result);
+		return result;
+	}
+
+	template = ima_template_desc_buf();
+	if (!template) {
+		pr_err("Failed to get ima-buf template\n");
+		return -EINVAL;
+	}
+
 	result = template_desc_init_fields(template->fmt,
 					   &(template->fields),
 					   &(template->num_fields));