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>

diff --git a/arch/powerpc/oprofile/cell/spu_task_sync.c b/arch/powerpc/oprofile/cell/spu_task_sync.c
index 642fca137ccb1489c593699b21115ed37c542883..28f1af2db1f564525dc374f3b7cf9eee0b5a1175 100644 (file)
--- a/arch/powerpc/oprofile/cell/spu_task_sync.c
+++ b/arch/powerpc/oprofile/cell/spu_task_sync.c
@@ -304,7 +304,7 @@ static inline unsigned long fast_get_dcookie(struct path *path)
        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 @@ get_exec_dcookie_and_offset(struct spu *spu, unsigned int *offsetp,
 {
        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 @@ get_exec_dcookie_and_offset(struct spu *spu, unsigned int *offsetp,
 
        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) {

diff --git a/arch/tile/mm/elf.c b/arch/tile/mm/elf.c
index 758b6038c2b78eabe41627ba5b018e289a0d677e..3cfa98bf9125215ae2fc7ea8fdc287fd84245285 100644 (file)
--- a/arch/tile/mm/elf.c
+++ b/arch/tile/mm/elf.c
@@ -36,19 +36,14 @@ static void sim_notify_exec(const char *binary_name)
        } 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);
@@ -106,16 +101,16 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
        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
         */

diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index f34b5b29fb955cb3129dd38f15296583ce64ff5e..d93b2b6b1f7a2b3598bb8fcc3bb9ba4d2231e626 100644 (file)
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -216,7 +216,7 @@ static inline unsigned long fast_get_dcookie(struct path *path)
 }
 
 
-/* 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 inline unsigned long fast_get_dcookie(struct path *path)
 static unsigned long get_exec_dcookie(struct mm_struct *mm)
 {
        unsigned long cookie = NO_COOKIE;
-       struct vm_area_struct *vma;
-
-       if (!mm)
-               goto out;
 
-       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;
-       }
+       if (mm && mm->exe_file)
+               cookie = fast_get_dcookie(&mm->exe_file->f_path);
 
-out:
        return cookie;
 }
 

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 4b96415527b8664753e18cb169f0de9f391f9314..31cf8854910b1f933f1cee4c9f7b372816d7d2db 100644 (file)
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1158,7 +1158,6 @@ static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk
 {
        char name[sizeof(tsk->comm)];
        struct mm_struct *mm = tsk->mm;
-       struct vm_area_struct *vma;
 
        /* tsk == current */
 
@@ -1168,16 +1167,8 @@ static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk
 
        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);

diff --git a/kernel/fork.c b/kernel/fork.c
index 2343c9eaaaf4e2e69def5b04b52bd7471305acbd..fbe806fb0dfd98cfeb942c9bb8017331ab979c6f 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -655,8 +655,7 @@ struct file *get_mm_exe_file(struct mm_struct *mm)
 {
        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)

diff --git a/security/tomoyo/util.c b/security/tomoyo/util.c
index 867558c983349d144c5f46a729af55a2a72dbe0a..2952ba576fb9ceed3f64c23663a2b40f3cfbe13e 100644 (file)
--- a/security/tomoyo/util.c
+++ b/security/tomoyo/util.c
@@ -949,18 +949,13 @@ bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
 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;
 }