Convert the selinux sysctl pathname computation code into a standalone function. Signed-off-by: Andreas Gruenbacher Signed-off-by: John Johansen Reviewed-by: James Morris --- include/linux/sysctl.h | 2 ++ kernel/sysctl.c | 27 +++++++++++++++++++++++++++ security/selinux/hooks.c | 35 +++++------------------------------ 3 files changed, 34 insertions(+), 30 deletions(-) --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -977,6 +977,8 @@ extern int proc_doulongvec_minmax(struct extern int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int, struct file *, void __user *, size_t *, loff_t *); +extern char *sysctl_pathname(ctl_table *, char *, int); + extern int do_sysctl (int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen); --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1443,6 +1443,33 @@ void register_sysctl_root(struct ctl_tab spin_unlock(&sysctl_lock); } +char *sysctl_pathname(ctl_table *table, char *buffer, int buflen) +{ + if (buflen < 1) + return NULL; + buffer += --buflen; + *buffer = '\0'; + + while (table) { + int namelen = strlen(table->procname); + + if (buflen < namelen + 1) + return NULL; + buflen -= namelen + 1; + buffer -= namelen; + memcpy(buffer, table->procname, namelen); + *--buffer = '/'; + table = table->parent; + } + if (buflen < 4) + return NULL; + buffer -= 4; + memcpy(buffer, "/sys", 4); + + return buffer; +} +EXPORT_SYMBOL(sysctl_pathname); + #ifdef CONFIG_SYSCTL_SYSCALL int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen) --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1659,40 +1659,15 @@ static int selinux_capable(struct task_s static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) { - int buflen, rc; - char *buffer, *path, *end; + char *buffer, *path; + int rc = -ENOMEM; - rc = -ENOMEM; buffer = (char*)__get_free_page(GFP_KERNEL); if (!buffer) goto out; - - buflen = PAGE_SIZE; - end = buffer+buflen; - *--end = '\0'; - buflen--; - path = end-1; - *path = '/'; - while (table) { - const char *name = table->procname; - size_t namelen = strlen(name); - buflen -= namelen + 1; - if (buflen < 0) - goto out_free; - end -= namelen; - memcpy(end, name, namelen); - *--end = '/'; - path = end; - table = table->parent; - } - buflen -= 4; - if (buflen < 0) - goto out_free; - end -= 4; - memcpy(end, "/sys", 4); - path = end; - rc = security_genfs_sid("proc", path, tclass, sid); -out_free: + path = sysctl_pathname(table, buffer, PAGE_SIZE); + if (path) + rc = security_genfs_sid("proc", path, tclass, sid); free_page((unsigned long)buffer); out: return rc; -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/