From 8abfb36ab396377ea712cd640c525fd5535d1dc9 Mon Sep 17 00:00:00 2001 From: Zhang Zhen Date: Tue, 15 Apr 2014 14:19:38 +0800 Subject: [PATCH] f2fs: atomically set inode->i_flags in f2fs_set_inode_flags() Use set_mask_bits() to atomically set i_flags instead of clearing out the S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the FS_IMMUTABLE_FL, FS_APPEND_FL, etc. flags, since this opens up a race where an immutable file has the immutable flag cleared for a brief window of time. Signed-off-by: Zhang Zhen Signed-off-by: Jaegeuk Kim --- fs/f2fs/inode.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index ee829d36046..f7a655373c4 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -12,6 +12,7 @@ #include #include #include +#include #include "f2fs.h" #include "node.h" @@ -21,20 +22,20 @@ void f2fs_set_inode_flags(struct inode *inode) { unsigned int flags = F2FS_I(inode)->i_flags; - - inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | - S_NOATIME | S_DIRSYNC); + unsigned int new_fl = 0; if (flags & FS_SYNC_FL) - inode->i_flags |= S_SYNC; + new_fl |= S_SYNC; if (flags & FS_APPEND_FL) - inode->i_flags |= S_APPEND; + new_fl |= S_APPEND; if (flags & FS_IMMUTABLE_FL) - inode->i_flags |= S_IMMUTABLE; + new_fl |= S_IMMUTABLE; if (flags & FS_NOATIME_FL) - inode->i_flags |= S_NOATIME; + new_fl |= S_NOATIME; if (flags & FS_DIRSYNC_FL) - inode->i_flags |= S_DIRSYNC; + new_fl |= S_DIRSYNC; + set_mask_bits(&inode->i_flags, + S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC, new_fl); } static void __get_inode_rdev(struct inode *inode, struct f2fs_inode *ri) -- 2.41.0