mm: use mm->exe_file instead of first VM_EXECUTABLE vma->vm_file

Some security modules and oprofile still uses VM_EXECUTABLE for retrieving a task's executable file. After this patch they will use mm->exe_file directly. mm->exe_file is protected with mm->mmap_sem, so locking stays the same. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [arch/tile] Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> [tomoyo] Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Acked-by: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: use mm->exe_file instead of first VM_EXECUTABLE vma->vm_file
Some security modules and oprofile still uses VM_EXECUTABLE for retrieving a task's executable file. After this patch they will use mm->exe_file directly. mm->exe_file is protected with mm->mmap_sem, so locking stays the same. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [arch/tile] Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> [tomoyo] Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Acked-by: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Konstantin Khlebnikov · Linus Torvalds
1 parent 0b173bc4da
Showing 6 changed files with 19 additions and 57 deletions Side-by-side Diff
arch/powerpc/oprofile/cell/spu_task_sync.c
arch/tile/mm/elf.c
drivers/oprofile/buffer_sync.c
kernel/auditsc.c
kernel/fork.c
security/tomoyo/util.c
@@ -304,7 +304,7 @@
 	return cookie;
 }
  
-/* Look up the dcookie for the task's first VM_EXECUTABLE mapping,
+/* Look up the dcookie for the task's mm->exe_file,
  * which corresponds loosely to "application name". Also, determine
  * the offset for the SPU ELF object.  If computed offset is
  * non-zero, it implies an embedded SPU object; otherwise, it's a
@@ -321,7 +321,6 @@
 {
 	unsigned long app_cookie = 0;
 	unsigned int my_offset = 0;
-	struct file *app = NULL;
 	struct vm_area_struct *vma;
 	struct mm_struct *mm = spu->mm;
  
  
@@ -330,16 +329,10 @@
  
 	down_read(&mm->mmap_sem);
  
-	for (vma = mm->mmap; vma; vma = vma->vm_next) {
-		if (!vma->vm_file)
-			continue;
-		if (!(vma->vm_flags & VM_EXECUTABLE))
-			continue;
-		app_cookie = fast_get_dcookie(&vma->vm_file->f_path);
+	if (mm->exe_file) {
+		app_cookie = fast_get_dcookie(&mm->exe_file->f_path);
 		pr_debug("got dcookie for %s\n",
-			 vma->vm_file->f_dentry->d_name.name);
-		app = vma->vm_file;
-		break;
+			 mm->exe_file->f_dentry->d_name.name);
 	}
  
 	for (vma = mm->mmap; vma; vma = vma->vm_next) {
@@ -36,19 +36,14 @@
 	} while (c);
 }
  
-static int notify_exec(void)
+static int notify_exec(struct mm_struct *mm)
 {
 	int retval = 0;  /* failure */
-	struct vm_area_struct *vma = current->mm->mmap;
-	while (vma) {
-		if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file)
-			break;
-		vma = vma->vm_next;
-	}
-	if (vma) {
+
+	if (mm->exe_file) {
 		char *buf = (char *) __get_free_page(GFP_KERNEL);
 		if (buf) {
-			char *path = d_path(&vma->vm_file->f_path,
+			char *path = d_path(&mm->exe_file->f_path,
 					    buf, PAGE_SIZE);
 			if (!IS_ERR(path)) {
 				sim_notify_exec(path);
  
  
@@ -106,15 +101,15 @@
 	unsigned long vdso_base;
 	int retval = 0;
  
+	down_write(&mm->mmap_sem);
+
 	/*
 	 * Notify the simulator that an exec just occurred.
 	 * If we can't find the filename of the mapping, just use
 	 * whatever was passed as the linux_binprm filename.
 	 */
-	if (!notify_exec())
+	if (!notify_exec(mm))
 		sim_notify_exec(bprm->filename);
-
-	down_write(&mm->mmap_sem);
  
 	/*
 	 * MAYWRITE to allow gdb to COW and set breakpoints
@@ -216,7 +216,7 @@
 }
  
  
-/* Look up the dcookie for the task's first VM_EXECUTABLE mapping,
+/* Look up the dcookie for the task's mm->exe_file,
  * which corresponds loosely to "application name". This is
  * not strictly necessary but allows oprofile to associate
  * shared-library samples with particular applications
  
  
@@ -224,21 +224,10 @@
 static unsigned long get_exec_dcookie(struct mm_struct *mm)
 {
 	unsigned long cookie = NO_COOKIE;
-	struct vm_area_struct *vma;
  
-	if (!mm)
-		goto out;
+	if (mm && mm->exe_file)
+		cookie = fast_get_dcookie(&mm->exe_file->f_path);
  
-	for (vma = mm->mmap; vma; vma = vma->vm_next) {
-		if (!vma->vm_file)
-			continue;
-		if (!(vma->vm_flags & VM_EXECUTABLE))
-			continue;
-		cookie = fast_get_dcookie(&vma->vm_file->f_path);
-		break;
-	}
-
-out:
 	return cookie;
 }
  
@@ -1151,7 +1151,6 @@
 	const struct cred *cred;
 	char name[sizeof(tsk->comm)];
 	struct mm_struct *mm = tsk->mm;
-	struct vm_area_struct *vma;
 	char *tty;
  
 	if (!ab)
@@ -1191,16 +1190,8 @@
  
 	if (mm) {
 		down_read(&mm->mmap_sem);
-		vma = mm->mmap;
-		while (vma) {
-			if ((vma->vm_flags & VM_EXECUTABLE) &&
-			    vma->vm_file) {
-				audit_log_d_path(ab, " exe=",
-						 &vma->vm_file->f_path);
-				break;
-			}
-			vma = vma->vm_next;
-		}
+		if (mm->exe_file)
+			audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
 		up_read(&mm->mmap_sem);
 	}
 	audit_log_task_context(ab);
@@ -656,8 +656,7 @@
 {
 	struct file *exe_file;
  
-	/* We need mmap_sem to protect against races with removal of
-	 * VM_EXECUTABLE vmas */
+	/* We need mmap_sem to protect against races with removal of exe_file */
 	down_read(&mm->mmap_sem);
 	exe_file = mm->exe_file;
 	if (exe_file)
@@ -949,18 +949,13 @@
 const char *tomoyo_get_exe(void)
 {
 	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
 	const char *cp = NULL;
  
 	if (!mm)
 		return NULL;
 	down_read(&mm->mmap_sem);
-	for (vma = mm->mmap; vma; vma = vma->vm_next) {
-		if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file) {
-			cp = tomoyo_realpath_from_path(&vma->vm_file->f_path);
-			break;
-		}
-	}
+	if (mm->exe_file)
+		cp = tomoyo_realpath_from_path(&mm->exe_file->f_path);
 	up_read(&mm->mmap_sem);
 	return cp;
 }
...	...	@@ -304,7 +304,7 @@
304	304	return cookie;
305	305	}
306	306
307		-/* Look up the dcookie for the task's first VM_EXECUTABLE mapping,
	307	+/* Look up the dcookie for the task's mm->exe_file,
308	308	* which corresponds loosely to "application name". Also, determine
309	309	* the offset for the SPU ELF object. If computed offset is
310	310	* non-zero, it implies an embedded SPU object; otherwise, it's a
...	...	@@ -321,7 +321,6 @@
321	321	{
322	322	unsigned long app_cookie = 0;
323	323	unsigned int my_offset = 0;
324		- struct file *app = NULL;
325	324	struct vm_area_struct *vma;
326	325	struct mm_struct *mm = spu->mm;
327	326
328	327
...	...	@@ -330,16 +329,10 @@
330	329
331	330	down_read(&mm->mmap_sem);
332	331
333		- for (vma = mm->mmap; vma; vma = vma->vm_next) {
334		- if (!vma->vm_file)
335		- continue;
336		- if (!(vma->vm_flags & VM_EXECUTABLE))
337		- continue;
338		- app_cookie = fast_get_dcookie(&vma->vm_file->f_path);
	332	+ if (mm->exe_file) {
	333	+ app_cookie = fast_get_dcookie(&mm->exe_file->f_path);
339	334	pr_debug("got dcookie for %s\n",
340		- vma->vm_file->f_dentry->d_name.name);
341		- app = vma->vm_file;
342		- break;
	335	+ mm->exe_file->f_dentry->d_name.name);
343	336	}
344	337
345	338	for (vma = mm->mmap; vma; vma = vma->vm_next) {
...	...	@@ -36,19 +36,14 @@
36	36	} while (c);
37	37	}
38	38
39		-static int notify_exec(void)
	39	+static int notify_exec(struct mm_struct *mm)
40	40	{
41	41	int retval = 0; /* failure */
42		- struct vm_area_struct *vma = current->mm->mmap;
43		- while (vma) {
44		- if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file)
45		- break;
46		- vma = vma->vm_next;
47		- }
48		- if (vma) {
	42	+
	43	+ if (mm->exe_file) {
49	44	char buf = (char ) __get_free_page(GFP_KERNEL);
50	45	if (buf) {
51		- char *path = d_path(&vma->vm_file->f_path,
	46	+ char *path = d_path(&mm->exe_file->f_path,
52	47	buf, PAGE_SIZE);
53	48	if (!IS_ERR(path)) {
54	49	sim_notify_exec(path);
55	50
56	51
...	...	@@ -106,15 +101,15 @@
106	101	unsigned long vdso_base;
107	102	int retval = 0;
108	103
	104	+ down_write(&mm->mmap_sem);
	105	+
109	106	/*
110	107	* Notify the simulator that an exec just occurred.
111	108	* If we can't find the filename of the mapping, just use
112	109	* whatever was passed as the linux_binprm filename.
113	110	*/
114		- if (!notify_exec())
	111	+ if (!notify_exec(mm))
115	112	sim_notify_exec(bprm->filename);
116		-
117		- down_write(&mm->mmap_sem);
118	113
119	114	/*
120	115	* MAYWRITE to allow gdb to COW and set breakpoints
...	...	@@ -216,7 +216,7 @@
216	216	}
217	217
218	218
219		-/* Look up the dcookie for the task's first VM_EXECUTABLE mapping,
	219	+/* Look up the dcookie for the task's mm->exe_file,
220	220	* which corresponds loosely to "application name". This is
221	221	* not strictly necessary but allows oprofile to associate
222	222	* shared-library samples with particular applications
223	223
224	224
...	...	@@ -224,21 +224,10 @@
224	224	static unsigned long get_exec_dcookie(struct mm_struct *mm)
225	225	{
226	226	unsigned long cookie = NO_COOKIE;
227		- struct vm_area_struct *vma;
228	227
229		- if (!mm)
230		- goto out;
	228	+ if (mm && mm->exe_file)
	229	+ cookie = fast_get_dcookie(&mm->exe_file->f_path);
231	230
232		- for (vma = mm->mmap; vma; vma = vma->vm_next) {
233		- if (!vma->vm_file)
234		- continue;
235		- if (!(vma->vm_flags & VM_EXECUTABLE))
236		- continue;
237		- cookie = fast_get_dcookie(&vma->vm_file->f_path);
238		- break;
239		- }
240		-
241		-out:
242	231	return cookie;
243	232	}
244	233
...	...	@@ -1151,7 +1151,6 @@
1151	1151	const struct cred *cred;
1152	1152	char name[sizeof(tsk->comm)];
1153	1153	struct mm_struct *mm = tsk->mm;
1154		- struct vm_area_struct *vma;
1155	1154	char *tty;
1156	1155
1157	1156	if (!ab)
...	...	@@ -1191,16 +1190,8 @@
1191	1190
1192	1191	if (mm) {
1193	1192	down_read(&mm->mmap_sem);
1194		- vma = mm->mmap;
1195		- while (vma) {
1196		- if ((vma->vm_flags & VM_EXECUTABLE) &&
1197		- vma->vm_file) {
1198		- audit_log_d_path(ab, " exe=",
1199		- &vma->vm_file->f_path);
1200		- break;
1201		- }
1202		- vma = vma->vm_next;
1203		- }
	1193	+ if (mm->exe_file)
	1194	+ audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
1204	1195	up_read(&mm->mmap_sem);
1205	1196	}
1206	1197	audit_log_task_context(ab);
...	...	@@ -656,8 +656,7 @@
656	656	{
657	657	struct file *exe_file;
658	658
659		- /* We need mmap_sem to protect against races with removal of
660		- * VM_EXECUTABLE vmas */
	659	+ /* We need mmap_sem to protect against races with removal of exe_file */
661	660	down_read(&mm->mmap_sem);
662	661	exe_file = mm->exe_file;
663	662	if (exe_file)
...	...	@@ -949,18 +949,13 @@
949	949	const char *tomoyo_get_exe(void)
950	950	{
951	951	struct mm_struct *mm = current->mm;
952		- struct vm_area_struct *vma;
953	952	const char *cp = NULL;
954	953
955	954	if (!mm)
956	955	return NULL;
957	956	down_read(&mm->mmap_sem);
958		- for (vma = mm->mmap; vma; vma = vma->vm_next) {
959		- if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file) {
960		- cp = tomoyo_realpath_from_path(&vma->vm_file->f_path);
961		- break;
962		- }
963		- }
	957	+ if (mm->exe_file)
	958	+ cp = tomoyo_realpath_from_path(&mm->exe_file->f_path);
964	959	up_read(&mm->mmap_sem);
965	960	return cp;
966	961	}