From cc1dad7183e4cb7f5d313b6942f2059fc0eabab6 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Mon, 2 Apr 2012 19:40:47 -0400
Subject: selinuxfs snprintf() misuses

a) %d does _not_ produce a page worth of output
b) snprintf() doesn't return negatives - it used to in old glibc, but
that's the kernel...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 security/selinux/selinuxfs.c | 36 +++++++-----------------------------
 1 file changed, 7 insertions(+), 29 deletions(-)

(limited to 'security')

diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index 4e93f9ef970b..3ad290251288 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -1259,12 +1259,8 @@ static int sel_make_bools(void)
 		if (!inode)
 			goto out;
 
-		ret = -EINVAL;
-		len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
-		if (len < 0)
-			goto out;
-
 		ret = -ENAMETOOLONG;
+		len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
 		if (len >= PAGE_SIZE)
 			goto out;
 
@@ -1557,19 +1553,10 @@ static inline u32 sel_ino_to_perm(unsigned long ino)
 static ssize_t sel_read_class(struct file *file, char __user *buf,
 				size_t count, loff_t *ppos)
 {
-	ssize_t rc, len;
-	char *page;
 	unsigned long ino = file->f_path.dentry->d_inode->i_ino;
-
-	page = (char *)__get_free_page(GFP_KERNEL);
-	if (!page)
-		return -ENOMEM;
-
-	len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
-	rc = simple_read_from_buffer(buf, count, ppos, page, len);
-	free_page((unsigned long)page);
-
-	return rc;
+	char res[TMPBUFLEN];
+	ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
+	return simple_read_from_buffer(buf, count, ppos, res, len);
 }
 
 static const struct file_operations sel_class_ops = {
@@ -1580,19 +1567,10 @@ static const struct file_operations sel_class_ops = {
 static ssize_t sel_read_perm(struct file *file, char __user *buf,
 				size_t count, loff_t *ppos)
 {
-	ssize_t rc, len;
-	char *page;
 	unsigned long ino = file->f_path.dentry->d_inode->i_ino;
-
-	page = (char *)__get_free_page(GFP_KERNEL);
-	if (!page)
-		return -ENOMEM;
-
-	len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
-	rc = simple_read_from_buffer(buf, count, ppos, page, len);
-	free_page((unsigned long)page);
-
-	return rc;
+	char res[TMPBUFLEN];
+	ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
+	return simple_read_from_buffer(buf, count, ppos, res, len);
 }
 
 static const struct file_operations sel_perm_ops = {
-- 
cgit v1.2.3


From d007794a182bc072a7b7479909dbd0d67ba341be Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 30 May 2012 13:11:37 -0400
Subject: split cap_mmap_addr() out of cap_file_mmap()

... switch callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/linux/security.h   |  3 ++-
 security/apparmor/lsm.c    |  2 +-
 security/commoncap.c       | 32 +++++++++++++++++++++++---------
 security/selinux/hooks.c   |  2 +-
 security/smack/smack_lsm.c |  2 +-
 5 files changed, 28 insertions(+), 13 deletions(-)

(limited to 'security')

diff --git a/include/linux/security.h b/include/linux/security.h
index ab0e091ce5fa..4ad59c9fa731 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -86,6 +86,7 @@ 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_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);
@@ -2187,7 +2188,7 @@ static inline int security_file_mmap(struct file *file, unsigned long reqprot,
 				     unsigned long addr,
 				     unsigned long addr_only)
 {
-	return cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
+	return cap_mmap_addr(addr);
 }
 
 static inline int security_file_mprotect(struct vm_area_struct *vma,
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 032daab449b0..8430d8937afb 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -497,7 +497,7 @@ static int apparmor_file_mmap(struct file *file, unsigned long reqprot,
 	int rc = 0;
 
 	/* do DAC check */
-	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
+	rc = cap_mmap_addr(addr);
 	if (rc || addr_only)
 		return rc;
 
diff --git a/security/commoncap.c b/security/commoncap.c
index e771cb1b2d79..ebac3618896e 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -958,22 +958,15 @@ int cap_vm_enough_memory(struct mm_struct *mm, long pages)
 }
 
 /*
- * cap_file_mmap - check if able to map given addr
- * @file: unused
- * @reqprot: unused
- * @prot: unused
- * @flags: unused
+ * cap_mmap_addr - check if able to map given addr
  * @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_addr(unsigned long addr)
 {
 	int ret = 0;
 
@@ -986,3 +979,24 @@ int cap_file_mmap(struct file *file, unsigned long reqprot,
 	}
 	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)
+{
+	return cap_mmap_addr(addr);
+}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index fa2341b68331..25c125eaa3d8 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3104,7 +3104,7 @@ static int selinux_file_mmap(struct file *file, unsigned long reqprot,
 	}
 
 	/* do DAC check on address space usage */
-	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
+	rc = cap_mmap_addr(addr);
 	if (rc || addr_only)
 		return rc;
 
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index d583c0545808..a62197718768 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1199,7 +1199,7 @@ static int smack_file_mmap(struct file *file,
 	int rc;
 
 	/* do DAC check on address space usage */
-	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
+	rc = cap_mmap_addr(addr);
 	if (rc || addr_only)
 		return rc;
 
-- 
cgit v1.2.3


From e5467859f7f79b69fc49004403009dfdba3bec53 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 30 May 2012 13:30:51 -0400
Subject: split ->file_mmap() into ->mmap_addr()/->mmap_file()

... i.e. file-dependent and address-dependent checks.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 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(-)

(limited to 'security')

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 @@ error:
 	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,
-- 
cgit v1.2.3


From 8b3ec6814c83d76b85bd13badc48552836c24839 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 30 May 2012 17:11:23 -0400
Subject: take security_mmap_file() outside of ->mmap_sem

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/linux/security.h |  7 +++----
 ipc/shm.c                |  5 +++++
 mm/mmap.c                | 23 ++++++++++++-----------
 mm/nommu.c               | 22 ++++++++++++----------
 security/security.c      | 33 ++++++++++++++++++++++++++++++---
 5 files changed, 62 insertions(+), 28 deletions(-)

(limited to 'security')

diff --git a/include/linux/security.h b/include/linux/security.h
index f1bae0963ddc..4e5a73cdbbef 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -1745,8 +1745,8 @@ 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_mmap_file(struct file *file, unsigned long reqprot,
-			unsigned long prot, unsigned long flags);
+int security_mmap_file(struct file *file, 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);
@@ -2183,8 +2183,7 @@ static inline int security_file_ioctl(struct file *file, unsigned int cmd,
 	return 0;
 }
 
-static inline int security_mmap_file(struct file *file, unsigned long reqprot,
-				     unsigned long prot,
+static inline int security_mmap_file(struct file *file, unsigned long prot,
 				     unsigned long flags)
 {
 	return 0;
diff --git a/ipc/shm.c b/ipc/shm.c
index 406c5b208193..e3a8063b1768 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1036,6 +1036,10 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 	sfd->file = shp->shm_file;
 	sfd->vm_ops = NULL;
 
+	err = security_mmap_file(file, prot, flags);
+	if (err)
+		goto out_fput;
+
 	down_write(&current->mm->mmap_sem);
 	if (addr && !(shmflg & SHM_REMAP)) {
 		err = -EINVAL;
@@ -1058,6 +1062,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 invalid:
 	up_write(&current->mm->mmap_sem);
 
+out_fput:
 	fput(file);
 
 out_nattch:
diff --git a/mm/mmap.c b/mm/mmap.c
index 49283da9a2ae..34b280f4238d 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -979,7 +979,6 @@ static unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 	struct inode *inode;
 	vm_flags_t vm_flags;
 	int error;
-	unsigned long reqprot = prot;
 
 	/*
 	 * Does the application expect PROT_READ to imply PROT_EXEC?
@@ -1105,10 +1104,6 @@ static unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 	if (error)
 		return error;
 
-	error = security_mmap_file(file, reqprot, prot, flags);
-	if (error)
-		return error;
-
 	return mmap_region(file, addr, len, flags, vm_flags, pgoff);
 }
 
@@ -1130,9 +1125,12 @@ unsigned long vm_mmap(struct file *file, unsigned long addr,
 	unsigned long ret;
 	struct mm_struct *mm = current->mm;
 
-	down_write(&mm->mmap_sem);
-	ret = do_mmap(file, addr, len, prot, flag, offset);
-	up_write(&mm->mmap_sem);
+	ret = security_mmap_file(file, prot, flag);
+	if (!ret) {
+		down_write(&mm->mmap_sem);
+		ret = do_mmap(file, addr, len, prot, flag, offset);
+		up_write(&mm->mmap_sem);
+	}
 	return ret;
 }
 EXPORT_SYMBOL(vm_mmap);
@@ -1168,9 +1166,12 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
 
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 
-	down_write(&current->mm->mmap_sem);
-	retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
+	retval = security_mmap_file(file, prot, flags);
+	if (!retval) {
+		down_write(&current->mm->mmap_sem);
+		retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+		up_write(&current->mm->mmap_sem);
+	}
 
 	if (file)
 		fput(file);
diff --git a/mm/nommu.c b/mm/nommu.c
index acfe419785db..8cbfd623b04a 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -889,7 +889,6 @@ static int validate_mmap_request(struct file *file,
 				 unsigned long *_capabilities)
 {
 	unsigned long capabilities, rlen;
-	unsigned long reqprot = prot;
 	int ret;
 
 	/* do the simple checks first */
@@ -1048,9 +1047,6 @@ static int validate_mmap_request(struct file *file,
 
 	/* allow the security API to have its say */
 	ret = security_mmap_addr(addr);
-	if (ret < 0)
-		return ret;
-	ret = security_mmap_file(file, reqprot, prot, flags);
 	if (ret < 0)
 		return ret;
 
@@ -1492,9 +1488,12 @@ unsigned long vm_mmap(struct file *file, unsigned long addr,
 	unsigned long ret;
 	struct mm_struct *mm = current->mm;
 
-	down_write(&mm->mmap_sem);
-	ret = do_mmap(file, addr, len, prot, flag, offset);
-	up_write(&mm->mmap_sem);
+	ret = security_mmap_file(file, prot, flag);
+	if (!ret) {
+		down_write(&mm->mmap_sem);
+		ret = do_mmap(file, addr, len, prot, flag, offset);
+		up_write(&mm->mmap_sem);
+	}
 	return ret;
 }
 EXPORT_SYMBOL(vm_mmap);
@@ -1515,9 +1514,12 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
 
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 
-	down_write(&current->mm->mmap_sem);
-	retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
+	ret = security_mmap_file(file, prot, flags);
+	if (!ret) {
+		down_write(&current->mm->mmap_sem);
+		retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+		up_write(&current->mm->mmap_sem);
+	}
 
 	if (file)
 		fput(file);
diff --git a/security/security.c b/security/security.c
index d91c66d3956b..3b11b3b72fe2 100644
--- a/security/security.c
+++ b/security/security.c
@@ -20,6 +20,9 @@
 #include <linux/ima.h>
 #include <linux/evm.h>
 #include <linux/fsnotify.h>
+#include <linux/mman.h>
+#include <linux/mount.h>
+#include <linux/personality.h>
 #include <net/flow.h>
 
 #define MAX_LSM_EVM_XATTR	2
@@ -657,11 +660,35 @@ int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	return security_ops->file_ioctl(file, cmd, arg);
 }
 
-int security_mmap_file(struct file *file, unsigned long reqprot,
-			unsigned long prot, unsigned long flags)
+int security_mmap_file(struct file *file, unsigned long prot,
+			unsigned long flags)
 {
+	unsigned long reqprot = prot;
 	int ret;
-
+	/*
+	 * Does the application expect PROT_READ to imply PROT_EXEC?
+	 *
+	 * (the exception is when the underlying filesystem is noexec
+	 *  mounted, in which case we dont add PROT_EXEC.)
+	 */
+	if (!(reqprot & PROT_READ))
+		goto out;
+	if (!(current->personality & READ_IMPLIES_EXEC))
+		goto out;
+	if (!file) {
+		prot |= PROT_EXEC;
+	} else if (!(file->f_path.mnt->mnt_flags & MNT_NOEXEC)) {
+#ifndef CONFIG_MMU
+		unsigned long caps = 0;
+		struct address_space *mapping = file->f_mapping;
+		if (mapping && mapping->backing_dev_info)
+			caps = mapping->backing_dev_info->capabilities;
+		if (!(caps & BDI_CAP_EXEC_MAP))
+			goto out;
+#endif
+		prot |= PROT_EXEC;
+	}
+out:
 	ret = security_ops->mmap_file(file, reqprot, prot, flags);
 	if (ret)
 		return ret;
-- 
cgit v1.2.3


From 98de59bfe4b2ff6344d9ad8e5296f80de5dcc5b6 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 30 May 2012 19:58:30 -0400
Subject: take calculation of final prot in security_mmap_file() into a helper

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 security/security.c | 46 ++++++++++++++++++++++++++++------------------
 1 file changed, 28 insertions(+), 18 deletions(-)

(limited to 'security')

diff --git a/security/security.c b/security/security.c
index 3b11b3b72fe2..3efc9b12aef4 100644
--- a/security/security.c
+++ b/security/security.c
@@ -660,36 +660,46 @@ int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	return security_ops->file_ioctl(file, cmd, arg);
 }
 
-int security_mmap_file(struct file *file, unsigned long prot,
-			unsigned long flags)
+static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
 {
-	unsigned long reqprot = prot;
-	int ret;
 	/*
-	 * Does the application expect PROT_READ to imply PROT_EXEC?
-	 *
-	 * (the exception is when the underlying filesystem is noexec
-	 *  mounted, in which case we dont add PROT_EXEC.)
+	 * Does we have PROT_READ and does the application expect
+	 * it to imply PROT_EXEC?  If not, nothing to talk about...
 	 */
-	if (!(reqprot & PROT_READ))
-		goto out;
+	if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
+		return prot;
 	if (!(current->personality & READ_IMPLIES_EXEC))
-		goto out;
-	if (!file) {
-		prot |= PROT_EXEC;
-	} else if (!(file->f_path.mnt->mnt_flags & MNT_NOEXEC)) {
+		return prot;
+	/*
+	 * if that's an anonymous mapping, let it.
+	 */
+	if (!file)
+		return prot | PROT_EXEC;
+	/*
+	 * ditto if it's not on noexec mount, except that on !MMU we need
+	 * BDI_CAP_EXEC_MMAP (== VM_MAYEXEC) in this case
+	 */
+	if (!(file->f_path.mnt->mnt_flags & MNT_NOEXEC)) {
 #ifndef CONFIG_MMU
 		unsigned long caps = 0;
 		struct address_space *mapping = file->f_mapping;
 		if (mapping && mapping->backing_dev_info)
 			caps = mapping->backing_dev_info->capabilities;
 		if (!(caps & BDI_CAP_EXEC_MAP))
-			goto out;
+			return prot;
 #endif
-		prot |= PROT_EXEC;
+		return prot | PROT_EXEC;
 	}
-out:
-	ret = security_ops->mmap_file(file, reqprot, prot, flags);
+	/* anything on noexec mount won't get PROT_EXEC */
+	return prot;
+}
+
+int security_mmap_file(struct file *file, unsigned long prot,
+			unsigned long flags)
+{
+	int ret;
+	ret = security_ops->mmap_file(file, prot,
+					mmap_prot(file, prot), flags);
 	if (ret)
 		return ret;
 	return ima_file_mmap(file, prot);
-- 
cgit v1.2.3