From e5467859f7f79b69fc49004403009dfdba3bec53 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 30 May 2012 13:30:51 -0400 Subject: [PATCH] split ->file_mmap() into ->mmap_addr()/->mmap_file() ... i.e. file-dependent and address-dependent checks. Signed-off-by: Al Viro --- fs/exec.c | 4 ---- include/linux/security.h | 36 ++++++++++++++++++++---------------- mm/mmap.c | 12 ++++++++---- mm/mremap.c | 4 ++-- mm/nommu.c | 5 ++++- security/apparmor/lsm.c | 15 ++++----------- security/capability.c | 3 ++- security/commoncap.c | 21 +++------------------ security/security.c | 12 ++++++++---- security/selinux/hooks.c | 15 ++++++++------- security/smack/smack_lsm.c | 15 +++++---------- 11 files changed, 64 insertions(+), 78 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 52c9e2ff6e6b..a79786a8d2c8 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -280,10 +280,6 @@ static int __bprm_mm_init(struct linux_binprm *bprm) vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); INIT_LIST_HEAD(&vma->anon_vma_chain); - err = security_file_mmap(NULL, 0, 0, 0, vma->vm_start, 1); - if (err) - goto err; - err = insert_vm_struct(mm, vma); if (err) goto err; diff --git a/include/linux/security.h b/include/linux/security.h index 4ad59c9fa731..f1bae0963ddc 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -87,9 +87,8 @@ 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_mmap_addr(unsigned long addr); -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_mmap_file(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags); 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); @@ -587,15 +586,17 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * simple integer value. When @arg represents a user space pointer, it * should never be used by the security module. * Return 0 if permission is granted. - * @file_mmap : + * @mmap_addr : + * Check permissions for a mmap operation at @addr. + * @addr contains virtual address that will be used for the operation. + * Return 0 if permission is granted. + * @mmap_file : * Check permissions for a mmap operation. The @file may be NULL, e.g. * if mapping anonymous memory. * @file contains the file structure for file to map (may be NULL). * @reqprot contains the protection requested by the application. * @prot contains the protection that will be applied by the kernel. * @flags contains the operational flags. - * @addr contains virtual address that will be used for the operation. - * @addr_only contains a boolean: 0 if file-backed VMA, otherwise 1. * Return 0 if permission is granted. * @file_mprotect: * Check permissions before changing memory access permissions. @@ -1482,10 +1483,10 @@ struct security_operations { void (*file_free_security) (struct file *file); int (*file_ioctl) (struct file *file, unsigned int cmd, unsigned long arg); - int (*file_mmap) (struct file *file, + int (*mmap_addr) (unsigned long addr); + int (*mmap_file) (struct file *file, unsigned long reqprot, unsigned long prot, - unsigned long flags, unsigned long addr, - unsigned long addr_only); + unsigned long flags); int (*file_mprotect) (struct vm_area_struct *vma, unsigned long reqprot, unsigned long prot); @@ -1744,9 +1745,9 @@ int security_file_permission(struct file *file, int mask); int security_file_alloc(struct file *file); void security_file_free(struct file *file); int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg); -int security_file_mmap(struct file *file, unsigned long reqprot, - unsigned long prot, unsigned long flags, - unsigned long addr, unsigned long addr_only); +int security_mmap_file(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags); +int security_mmap_addr(unsigned long addr); int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, unsigned long prot); int security_file_lock(struct file *file, unsigned int cmd); @@ -2182,11 +2183,14 @@ static inline int security_file_ioctl(struct file *file, unsigned int cmd, return 0; } -static inline int security_file_mmap(struct file *file, unsigned long reqprot, +static inline int security_mmap_file(struct file *file, unsigned long reqprot, unsigned long prot, - unsigned long flags, - unsigned long addr, - unsigned long addr_only) + unsigned long flags) +{ + return 0; +} + +static inline int security_mmap_addr(unsigned long addr) { return cap_mmap_addr(addr); } diff --git a/mm/mmap.c b/mm/mmap.c index 83c56624f1f6..49283da9a2ae 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1101,7 +1101,11 @@ static unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, } } - error = security_file_mmap(file, reqprot, prot, flags, addr, 0); + error = security_mmap_addr(addr); + if (error) + return error; + + error = security_mmap_file(file, reqprot, prot, flags); if (error) return error; @@ -1817,7 +1821,7 @@ int expand_downwards(struct vm_area_struct *vma, return -ENOMEM; address &= PAGE_MASK; - error = security_file_mmap(NULL, 0, 0, 0, address, 1); + error = security_mmap_addr(address); if (error) return error; @@ -2205,7 +2209,7 @@ static unsigned long do_brk(unsigned long addr, unsigned long len) if (!len) return addr; - error = security_file_mmap(NULL, 0, 0, 0, addr, 1); + error = security_mmap_addr(addr); if (error) return error; @@ -2561,7 +2565,7 @@ int install_special_mapping(struct mm_struct *mm, vma->vm_ops = &special_mapping_vmops; vma->vm_private_data = pages; - ret = security_file_mmap(NULL, 0, 0, 0, vma->vm_start, 1); + ret = security_mmap_addr(vma->vm_start); if (ret) goto out; diff --git a/mm/mremap.c b/mm/mremap.c index 169c53b87749..ebf10892b63d 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -371,7 +371,7 @@ static unsigned long mremap_to(unsigned long addr, if ((addr <= new_addr) && (addr+old_len) > new_addr) goto out; - ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1); + ret = security_mmap_addr(new_addr); if (ret) goto out; @@ -532,7 +532,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, goto out; } - ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1); + ret = security_mmap_addr(new_addr); if (ret) goto out; ret = move_vma(vma, addr, old_len, new_len, new_addr); diff --git a/mm/nommu.c b/mm/nommu.c index de6084e3a046..acfe419785db 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1047,7 +1047,10 @@ static int validate_mmap_request(struct file *file, } /* allow the security API to have its say */ - ret = security_file_mmap(file, reqprot, prot, flags, addr, 0); + ret = security_mmap_addr(addr); + if (ret < 0) + return ret; + ret = security_mmap_file(file, reqprot, prot, flags); if (ret < 0) return ret; diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 8430d8937afb..8ea39aabe948 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -490,17 +490,9 @@ static int common_mmap(int op, struct file *file, unsigned long prot, return common_file_perm(op, file, mask); } -static int apparmor_file_mmap(struct file *file, unsigned long reqprot, - unsigned long prot, unsigned long flags, - unsigned long addr, unsigned long addr_only) +static int apparmor_mmap_file(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags) { - int rc = 0; - - /* do DAC check */ - rc = cap_mmap_addr(addr); - if (rc || addr_only) - return rc; - return common_mmap(OP_FMMAP, file, prot, flags); } @@ -646,7 +638,8 @@ static struct security_operations apparmor_ops = { .file_permission = apparmor_file_permission, .file_alloc_security = apparmor_file_alloc_security, .file_free_security = apparmor_file_free_security, - .file_mmap = apparmor_file_mmap, + .mmap_file = apparmor_mmap_file, + .mmap_addr = cap_mmap_addr, .file_mprotect = apparmor_file_mprotect, .file_lock = apparmor_file_lock, diff --git a/security/capability.c b/security/capability.c index fca889676c5e..61095df8b89a 100644 --- a/security/capability.c +++ b/security/capability.c @@ -949,7 +949,8 @@ void __init security_fixup_ops(struct security_operations *ops) set_to_cap_if_null(ops, file_alloc_security); set_to_cap_if_null(ops, file_free_security); set_to_cap_if_null(ops, file_ioctl); - set_to_cap_if_null(ops, file_mmap); + set_to_cap_if_null(ops, mmap_addr); + set_to_cap_if_null(ops, mmap_file); set_to_cap_if_null(ops, file_mprotect); set_to_cap_if_null(ops, file_lock); set_to_cap_if_null(ops, file_fcntl); diff --git a/security/commoncap.c b/security/commoncap.c index ebac3618896e..6dbae4650abe 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -980,23 +980,8 @@ int cap_mmap_addr(unsigned long addr) return ret; } -/* - * 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 dac_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 cap_mmap_file(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags) { - return cap_mmap_addr(addr); + return 0; } diff --git a/security/security.c b/security/security.c index 5497a57fba01..d91c66d3956b 100644 --- a/security/security.c +++ b/security/security.c @@ -657,18 +657,22 @@ int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return security_ops->file_ioctl(file, cmd, arg); } -int security_file_mmap(struct file *file, unsigned long reqprot, - unsigned long prot, unsigned long flags, - unsigned long addr, unsigned long addr_only) +int security_mmap_file(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags) { int ret; - ret = security_ops->file_mmap(file, reqprot, prot, flags, addr, addr_only); + ret = security_ops->mmap_file(file, reqprot, prot, flags); if (ret) return ret; return ima_file_mmap(file, prot); } +int security_mmap_addr(unsigned long addr) +{ + return security_ops->mmap_addr(addr); +} + int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, unsigned long prot) { diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 25c125eaa3d8..372ec6502aa8 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3083,9 +3083,7 @@ static int file_map_prot_check(struct file *file, unsigned long prot, int shared return rc; } -static int selinux_file_mmap(struct file *file, unsigned long reqprot, - unsigned long prot, unsigned long flags, - unsigned long addr, unsigned long addr_only) +static int selinux_mmap_addr(unsigned long addr) { int rc = 0; u32 sid = current_sid(); @@ -3104,10 +3102,12 @@ static int selinux_file_mmap(struct file *file, unsigned long reqprot, } /* do DAC check on address space usage */ - rc = cap_mmap_addr(addr); - if (rc || addr_only) - return rc; + return cap_mmap_addr(addr); +} +static int selinux_mmap_file(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags) +{ if (selinux_checkreqprot) prot = reqprot; @@ -5570,7 +5570,8 @@ static struct security_operations selinux_ops = { .file_alloc_security = selinux_file_alloc_security, .file_free_security = selinux_file_free_security, .file_ioctl = selinux_file_ioctl, - .file_mmap = selinux_file_mmap, + .mmap_file = selinux_mmap_file, + .mmap_addr = selinux_mmap_addr, .file_mprotect = selinux_file_mprotect, .file_lock = selinux_file_lock, .file_fcntl = selinux_file_fcntl, diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index a62197718768..ee0bb5735f35 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -1171,7 +1171,7 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd, } /** - * smack_file_mmap : + * smack_mmap_file : * Check permissions for a mmap operation. The @file may be NULL, e.g. * if mapping anonymous memory. * @file contains the file structure for file to map (may be NULL). @@ -1180,10 +1180,9 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd, * @flags contains the operational flags. * Return 0 if permission is granted. */ -static int smack_file_mmap(struct file *file, +static int smack_mmap_file(struct file *file, unsigned long reqprot, unsigned long prot, - unsigned long flags, unsigned long addr, - unsigned long addr_only) + unsigned long flags) { struct smack_known *skp; struct smack_rule *srp; @@ -1198,11 +1197,6 @@ static int smack_file_mmap(struct file *file, int tmay; int rc; - /* do DAC check on address space usage */ - rc = cap_mmap_addr(addr); - if (rc || addr_only) - return rc; - if (file == NULL || file->f_dentry == NULL) return 0; @@ -3482,7 +3476,8 @@ struct security_operations smack_ops = { .file_ioctl = smack_file_ioctl, .file_lock = smack_file_lock, .file_fcntl = smack_file_fcntl, - .file_mmap = smack_file_mmap, + .mmap_file = smack_mmap_file, + .mmap_addr = cap_mmap_addr, .file_set_fowner = smack_file_set_fowner, .file_send_sigiotask = smack_file_send_sigiotask, .file_receive = smack_file_receive, -- GitLab