From 92b9965066d7cc672e8c7a015081c6aa675cb5be Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Tue, 14 Aug 2012 13:22:36 +1000 Subject: [PATCH] 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 Acked-by: Chris Metcalf [arch/tile] Acked-by: Tetsuo Handa [tomoyo] Cc: Alexander Viro Cc: Carsten Otte Cc: Cyrill Gorcunov Cc: Eric Paris Cc: H. Peter Anvin Cc: Hugh Dickins Cc: Ingo Molnar Acked-by: James Morris Cc: Jason Baron Cc: Kentaro Takeda Cc: Matt Helsley Cc: Nick Piggin Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Robert Richter Cc: Suresh Siddha Cc: Venkatesh Pallipadi Acked-by: Linus Torvalds Signed-off-by: Andrew Morton --- arch/powerpc/oprofile/cell/spu_task_sync.c | 15 ++++----------- arch/tile/mm/elf.c | 19 +++++++------------ drivers/oprofile/buffer_sync.c | 17 +++-------------- kernel/auditsc.c | 13 ++----------- kernel/fork.c | 3 +-- security/tomoyo/util.c | 9 ++------- 6 files changed, 19 insertions(+), 57 deletions(-) diff --git a/arch/powerpc/oprofile/cell/spu_task_sync.c b/arch/powerpc/oprofile/cell/spu_task_sync.c index 642fca137ccb..28f1af2db1f5 100644 --- 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 758b6038c2b7..3cfa98bf9125 100644 --- 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 f34b5b29fb95..d93b2b6b1f7a 100644 --- 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 4b96415527b8..31cf8854910b 100644 --- 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 3bd2280d79f6..e26cdf47d939 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -657,8 +657,7 @@ 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 867558c98334..2952ba576fb9 100644 --- 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; } -- 2.39.5