Merge branch 'akpm' (patches from Andrew)

Merge third patch-bomb from Andrew Morton:
 "I'm pretty much done for -rc1 now:

   - the rest of MM, basically

   - lib/ updates

   - checkpatch, epoll, hfs, fatfs, ptrace, coredump, exit

   - cpu_mask simplifications

   - kexec, rapidio, MAINTAINERS etc, etc.

   - more dma-mapping cleanups/simplifications from hch"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (109 commits)
  MAINTAINERS: add/fix git URLs for various subsystems
  mm: memcontrol: add "sock" to cgroup2 memory.stat
  mm: memcontrol: basic memory statistics in cgroup2 memory controller
  mm: memcontrol: do not uncharge old page in page cache replacement
  Documentation: cgroup: add memory.swap.{current,max} description
  mm: free swap cache aggressively if memcg swap is full
  mm: vmscan: do not scan anon pages if memcg swap limit is hit
  swap.h: move memcg related stuff to the end of the file
  mm: memcontrol: replace mem_cgroup_lruvec_online with mem_cgroup_online
  mm: vmscan: pass memcg to get_scan_count()
  mm: memcontrol: charge swap to cgroup2
  mm: memcontrol: clean up alloc, online, offline, free functions
  mm: memcontrol: flatten struct cg_proto
  mm: memcontrol: rein in the CONFIG space madness
  net: drop tcp_memcontrol.c
  mm: memcontrol: introduce CONFIG_MEMCG_LEGACY_KMEM
  mm: memcontrol: allow to disable kmem accounting for cgroup2
  mm: memcontrol: account "kmem" consumers in cgroup2 memory controller
  mm: memcontrol: move kmem accounting code to CONFIG_MEMCG
  mm: memcontrol: separate kmem code from legacy tcp accounting code
  ...

1 files changed, 10 insertions, 10 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index 6af9212ab5aa..78947de6f969 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1853,11 +1853,13 @@ static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data
 		user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
 	}
 
-	if (prctl_map.exe_fd != (u32)-1)
+	if (prctl_map.exe_fd != (u32)-1) {
 		error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd);
-	down_read(&mm->mmap_sem);
-	if (error)
-		goto out;
+		if (error)
+			return error;
+	}
+
+	down_write(&mm->mmap_sem);
 
 	/*
 	 * We don't validate if these members are pointing to
@@ -1894,10 +1896,8 @@ static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data
 	if (prctl_map.auxv_size)
 		memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
 
-	error = 0;
-out:
-	up_read(&mm->mmap_sem);
-	return error;
+	up_write(&mm->mmap_sem);
+	return 0;
 }
 #endif /* CONFIG_CHECKPOINT_RESTORE */
 
@@ -1963,7 +1963,7 @@ static int prctl_set_mm(int opt, unsigned long addr,
 
 	error = -EINVAL;
 
-	down_read(&mm->mmap_sem);
+	down_write(&mm->mmap_sem);
 	vma = find_vma(mm, addr);
 
 	prctl_map.start_code	= mm->start_code;
@@ -2056,7 +2056,7 @@ static int prctl_set_mm(int opt, unsigned long addr,
 
 	error = 0;
 out:
-	up_read(&mm->mmap_sem);
+	up_write(&mm->mmap_sem);
 	return error;
 }