Commit 44be2f65 authored by Rasmus Villemoes's avatar Rasmus Villemoes Committed by Paul Moore
Browse files

selinux: introduce security_context_str_to_sid 



There seems to be a little confusion as to whether the scontext_len
parameter of security_context_to_sid() includes the nul-byte or
not. Reading security_context_to_sid_core(), it seems that the
expectation is that it does not (both the string copying and the test
for scontext_len being zero hint at that).

Introduce the helper security_context_str_to_sid() to do the strlen()
call and fix all callers.

Signed-off-by: default avatarRasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: default avatarStephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: default avatarPaul Moore <pmoore@redhat.com>
parent 44d37ad3

security/selinux/hooks.c

+4 −8
Original line number Diff line number Diff line
@@ -674,10 +674,9 @@ static int selinux_set_mnt_opts(struct super_block *sb, 


		if (flags[i] == SBLABEL_MNT)

			continue;

		rc = security_context_to_sid(mount_options[i],

					     strlen(mount_options[i]), &sid, GFP_KERNEL);

		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);

		if (rc) {

			printk(KERN_WARNING "SELinux: security_context_to_sid"

			printk(KERN_WARNING "SELinux: security_context_str_to_sid"

			       "(%s) failed for (dev %s, type %s) errno=%d\n",

			       mount_options[i], sb->s_id, name, rc);

			goto out;
@@ -2617,15 +2616,12 @@ static int selinux_sb_remount(struct super_block *sb, void *data) 


	for (i = 0; i < opts.num_mnt_opts; i++) {

		u32 sid;

		size_t len;



		if (flags[i] == SBLABEL_MNT)

			continue;

		len = strlen(mount_options[i]);

		rc = security_context_to_sid(mount_options[i], len, &sid,

					     GFP_KERNEL);

		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);

		if (rc) {

			printk(KERN_WARNING "SELinux: security_context_to_sid"

			printk(KERN_WARNING "SELinux: security_context_str_to_sid"

			       "(%s) failed for (dev %s, type %s) errno=%d\n",

			       mount_options[i], sb->s_id, sb->s_type->name, rc);

			goto out_free_opts;

security/selinux/include/security.h

+2 −0
Original line number Diff line number Diff line
@@ -166,6 +166,8 @@ int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len); 
int security_context_to_sid(const char *scontext, u32 scontext_len,

			    u32 *out_sid, gfp_t gfp);



int security_context_str_to_sid(const char *scontext, u32 *out_sid, gfp_t gfp);



int security_context_to_sid_default(const char *scontext, u32 scontext_len,

				    u32 *out_sid, u32 def_sid, gfp_t gfp_flags);

security/selinux/selinuxfs.c

+9 −17
Original line number Diff line number Diff line
@@ -731,13 +731,11 @@ static ssize_t sel_write_access(struct file *file, char *buf, size_t size) 
	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)

		goto out;



	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid,

					 GFP_KERNEL);

	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);

	if (length)

		goto out;



	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid,

					 GFP_KERNEL);

	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);

	if (length)

		goto out;
@@ -819,13 +817,11 @@ static ssize_t sel_write_create(struct file *file, char *buf, size_t size) 
		objname = namebuf;

	}



	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid,

					 GFP_KERNEL);

	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);

	if (length)

		goto out;



	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid,

					 GFP_KERNEL);

	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);

	if (length)

		goto out;
@@ -882,13 +878,11 @@ static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size) 
	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)

		goto out;



	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid,

					 GFP_KERNEL);

	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);

	if (length)

		goto out;



	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid,

					 GFP_KERNEL);

	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);

	if (length)

		goto out;
@@ -940,7 +934,7 @@ static ssize_t sel_write_user(struct file *file, char *buf, size_t size) 
	if (sscanf(buf, "%s %s", con, user) != 2)

		goto out;



	length = security_context_to_sid(con, strlen(con) + 1, &sid, GFP_KERNEL);

	length = security_context_str_to_sid(con, &sid, GFP_KERNEL);

	if (length)

		goto out;
@@ -1000,13 +994,11 @@ static ssize_t sel_write_member(struct file *file, char *buf, size_t size) 
	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)

		goto out;



	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid,

					 GFP_KERNEL);

	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);

	if (length)

		goto out;



	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid,

					 GFP_KERNEL);

	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);

	if (length)

		goto out;

security/selinux/ss/services.c

+5 −0
Original line number Diff line number Diff line
@@ -1476,6 +1476,11 @@ int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid, 
					    sid, SECSID_NULL, gfp, 0);

}



int security_context_str_to_sid(const char *scontext, u32 *sid, gfp_t gfp)

{

	return security_context_to_sid(scontext, strlen(scontext), sid, gfp);

}



/**

 * security_context_to_sid_default - Obtain a SID for a given security context,

 * falling back to specified default if needed.

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