fs: provide rcu-walk aware permission i_ops

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

1 files changed, 4 insertions, 1 deletions

diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index c9097f43b425..09a1f92a34ef 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -295,7 +295,7 @@ out:
         return ret;
 }
 
-static int proc_sys_permission(struct inode *inode, int mask)
+static int proc_sys_permission(struct inode *inode, int mask,unsigned int flags)
 {
         /*
          * sysctl entries that are not writeable,
@@ -305,6 +305,9 @@ static int proc_sys_permission(struct inode *inode, int mask)
         struct ctl_table *table;
         int error;
 
+        if (flags & IPERM_FLAG_RCU)
+                return -ECHILD;
+
         /* Executable files are not allowed under /proc/sys/ */
         if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))
                 return -EACCES;