diff options
| -rw-r--r-- | include/linux/security.h | 7 | ||||
| -rw-r--r-- | security/capability.c | 9 | ||||
| -rw-r--r-- | security/commoncap.c | 30 |
3 files changed, 34 insertions, 12 deletions
diff --git a/include/linux/security.h b/include/linux/security.h index 145909165dbf..963a48fc3005 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -66,6 +66,9 @@ extern int cap_inode_setxattr(struct dentry *dentry, const char *name, extern int cap_inode_removexattr(struct dentry *dentry, const char *name); extern int cap_inode_need_killpriv(struct dentry *dentry); extern int cap_inode_killpriv(struct dentry *dentry); +extern int cap_file_mmap(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags, + unsigned long addr, unsigned long addr_only); extern int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags); extern int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, unsigned long arg4, unsigned long arg5); @@ -2197,9 +2200,7 @@ static inline int security_file_mmap(struct file *file, unsigned long reqprot, unsigned long addr, unsigned long addr_only) { - if ((addr < mmap_min_addr) && !capable(CAP_SYS_RAWIO)) - return -EACCES; - return 0; + return cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); } static inline int security_file_mprotect(struct vm_area_struct *vma, diff --git a/security/capability.c b/security/capability.c index f218dd361647..ec0573054024 100644 --- a/security/capability.c +++ b/security/capability.c @@ -330,15 +330,6 @@ static int cap_file_ioctl(struct file *file, unsigned int command, return 0; } -static int cap_file_mmap(struct file *file, unsigned long reqprot, - unsigned long prot, unsigned long flags, - unsigned long addr, unsigned long addr_only) -{ - if ((addr < mmap_min_addr) && !capable(CAP_SYS_RAWIO)) - return -EACCES; - return 0; -} - static int cap_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, unsigned long prot) { diff --git a/security/commoncap.c b/security/commoncap.c index aa97704564d4..3852e9432801 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -984,3 +984,33 @@ int cap_vm_enough_memory(struct mm_struct *mm, long pages) cap_sys_admin = 1; return __vm_enough_memory(mm, pages, cap_sys_admin); } + +/* + * cap_file_mmap - check if able to map given addr + * @file: unused + * @reqprot: unused + * @prot: unused + * @flags: unused + * @addr: address attempting to be mapped + * @addr_only: unused + * + * If the process is attempting to map memory below mmap_min_addr they need + * CAP_SYS_RAWIO. The other parameters to this function are unused by the + * capability security module. Returns 0 if this mapping should be allowed + * -EPERM if not. + */ +int cap_file_mmap(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags, + unsigned long addr, unsigned long addr_only) +{ + int ret = 0; + + if (addr < mmap_min_addr) { + ret = cap_capable(current, current_cred(), CAP_SYS_RAWIO, + SECURITY_CAP_AUDIT); + /* set PF_SUPERPRIV if it turns out we allow the low mmap */ + if (ret == 0) + current->flags |= PF_SUPERPRIV; + } + return ret; +} |