From 44be2f65d979291ffb2a47112449507ffe1f9726 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 21 Oct 2015 17:44:25 -0400 Subject: 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: Rasmus Villemoes Acked-by: Stephen Smalley Signed-off-by: Paul Moore --- security/selinux/hooks.c | 12 ++++-------- security/selinux/include/security.h | 2 ++ security/selinux/selinuxfs.c | 26 +++++++++----------------- security/selinux/ss/services.c | 5 +++++ 4 files changed, 20 insertions(+), 25 deletions(-) (limited to 'security') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 7cd71cea0503..9ed1b5dbcb39 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -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; diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index 6a681d26bf20..223e9fd15d66 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -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); diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 5bed7716f8ab..c02da25d7b63 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -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; diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index b7df12ba61d8..c550df0e0ff1 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -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. -- cgit v1.2.3-59-g8ed1b