Commit 38e3eaee authored Nov 03, 2009 by Tyler Hicks

eCryptfs: Remove mmap from directory operations

Adrian reported that mkfontscale didn't work inside of eCryptfs mounts.
Strace revealed the following:

open("./", O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY|O_CLOEXEC) = 3
fcntl64(3, F_GETFD) = 0x1 (flags FD_CLOEXEC)
open("./fonts.scale", O_WRONLY|O_CREAT|O_TRUNC, 0666) = 4
getdents(3, /* 80 entries */, 32768) = 2304
open("./.", O_RDONLY) = 5
fcntl64(5, F_SETFD, FD_CLOEXEC) = 0
fstat64(5, {st_mode=S_IFDIR|0755, st_size=16384, ...}) = 0
mmap2(NULL, 16384, PROT_READ, MAP_PRIVATE, 5, 0) = 0xb7fcf000
close(5) = 0
--- SIGBUS (Bus error) @ 0 (0) ---
+++ killed by SIGBUS +++

The mmap2() on a directory was successful, resulting in a SIGBUS
signal later.  This patch removes mmap() from the list of possible
ecryptfs_dir_fops so that mmap() isn't possible on eCryptfs directory
files.

https://bugs.launchpad.net/ecryptfs/+bug/400443



Reported-by: Adrian C. <anrxc@sysphere.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>

parent f8f484d1

fs/ecryptfs/file.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -299,7 +299,6 @@ static int ecryptfs_ioctl(struct inode inode, struct file file,
		const struct file_operations ecryptfs_dir_fops = {
		.readdir = ecryptfs_readdir,
		.ioctl = ecryptfs_ioctl,
		.mmap = generic_file_mmap,
		.open = ecryptfs_open,
		.flush = ecryptfs_flush,
		.release = ecryptfs_release,

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