Re: [PATCH 2/3 v2] fs: Prevent doing FALLOC_FL_ZERO_RANGE on append only file

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Apr 15, 2014 at 06:41:15PM +0200, Lukas Czerner wrote:
> Currently punch hole and collapse range fallocate operation are not
> allowed on append only file. This should be case for zero range as well.
> Fix it by allowing only pure fallocate (possibly with keep size set).
> 
> Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx>
> ---
> v2: Change the condition to be future proof as suggested by hch
> 
>  fs/open.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/open.c b/fs/open.c
> index 631aea81..fe48b2f 100644
> --- a/fs/open.c
> +++ b/fs/open.c
> @@ -254,11 +254,9 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
>  		return -EBADF;
>  
>  	/*
> -	 * It's not possible to punch hole or perform collapse range
> -	 * on append only file
> +	 * We can only allow pure fallocate on append only files
>  	 */
> -	if (mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_COLLAPSE_RANGE)
> -	    && IS_APPEND(inode))
> +	if (mode & ~FALLOC_FL_KEEP_SIZE && IS_APPEND(inode))

	if ((mode & ~FALLOC_FL_KEEP_SIZE) && IS_APPEND(inode))

gcc normally complains when you mix & and && in the same logic
statement without () to separate the logic. I agree with gcc here,
because the () indicate the intent of the logic and make it easy to
determine that the & and && haven't been mixed up or fat-fingered...

Cheers,

Dave.
-- 
Dave Chinner
david@xxxxxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]
  Powered by Linux