[Devel] [PATCH 01/13] fs: exec_mmap() arg corrected

[Alexander Mikhalitsyn]

From: Konstantin Khorenko <khorenko at virtuozzo.com>

---

VZ 8 rebase part https://jira.sw.ru/browse/PSBM-127782

Signed-off-by: Alexander Mikhalitsyn <alexander.mikhalitsyn at virtuozzo.com>
Signed-off-by: Konstantin Khorenko <khorenko at virtuozzo.com>
---
 fs/exec.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/fs/exec.c b/fs/exec.c
index c036db0323e0..dfaedb7323bb 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1003,10 +1003,10 @@ ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len)
 }
 EXPORT_SYMBOL(read_code);
 
-static int exec_mmap(struct mm_struct *mm)
+static int exec_mmap(struct linux_binprm *bprm)
 {
 	struct task_struct *tsk;
-	struct mm_struct *old_mm, *active_mm;
+	struct mm_struct *old_mm, *active_mm, *mm;
 
 	/* Notify parent that we're no longer interested in the old VM */
 	tsk = current;
@@ -1028,6 +1028,7 @@ static int exec_mmap(struct mm_struct *mm)
 		}
 	}
 
+	mm = bprm->mm;
 	mm->vps_dumpable = VD_PTRACE_COREDUMP;
 	task_lock(tsk);
 	active_mm = tsk->active_mm;
@@ -1038,6 +1039,8 @@ static int exec_mmap(struct mm_struct *mm)
 	tsk->mm->vmacache_seqnum = 0;
 	vmacache_flush(tsk);
 	task_unlock(tsk);
+	bprm->mm = NULL;		/* We're using it now */
+
 	if (old_mm) {
 		up_read(&old_mm->mmap_sem);
 		BUG_ON(active_mm != old_mm);
@@ -1276,18 +1279,10 @@ int flush_old_exec(struct linux_binprm * bprm)
 	 * Release all of the old mmap stuff
 	 */
 	acct_arg_size(bprm, 0);
-	retval = exec_mmap(bprm->mm);
+	retval = exec_mmap(bprm);
 	if (retval)
 		goto out;
 
-	/*
-	 * After clearing bprm->mm (to mark that current is using the
-	 * prepared mm now), we have nothing left of the original
-	 * process. If anything from here on returns an error, the check
-	 * in search_binary_handler() will SEGV current.
-	 */
-	bprm->mm = NULL;
-
 	set_fs(USER_DS);
 	current->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD |
 					PF_NOFREEZE | PF_NO_SETAFFINITY);
-- 
2.28.0