From aeee71b15f54426f02f41a4408afbd0b5acab7ec Mon Sep 17 00:00:00 2001 From: "Liam R. Howlett" Date: Wed, 7 Apr 2021 11:39:06 -0400 Subject: [PATCH] arch/m68k/kernel/sys_m68k: Add missing mmap_read_lock() to sys_cacheflush() When the superuser flushes the entire cache, the mmap_read_lock() is not taken, but mmap_read_unlock() is called. Add the missing mmap_read_lock() call. Fixes: cd2567b6850b (m68k: call find_vma with the mmap_sem held in sys_cacheflush()) Signed-off-by: Liam R. Howlett --- arch/m68k/kernel/sys_m68k.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/m68k/kernel/sys_m68k.c b/arch/m68k/kernel/sys_m68k.c index 1c235d8f53f3..f55bdcb8e4f1 100644 --- a/arch/m68k/kernel/sys_m68k.c +++ b/arch/m68k/kernel/sys_m68k.c @@ -388,6 +388,8 @@ sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len) ret = -EPERM; if (!capable(CAP_SYS_ADMIN)) goto out; + + mmap_read_lock(current->mm); } else { struct vm_area_struct *vma; -- 2.30.0