From 38e3eaeedcac75360af8a92e7b66956ec4f334e5 Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Tue, 3 Nov 2009 14:56:06 -0600 Subject: 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. Signed-off-by: Tyler Hicks --- fs/ecryptfs/file.c | 1 - 1 file changed, 1 deletion(-) (limited to 'fs/ecryptfs/file.c') diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c index 9e944057001b..3efc7fdc3c39 100644 --- a/fs/ecryptfs/file.c +++ b/fs/ecryptfs/file.c @@ -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, -- cgit v1.2.2 From e27759d7a333d1f25d628c4f7caf845c51be51c2 Mon Sep 17 00:00:00 2001 From: Erez Zadok Date: Thu, 3 Dec 2009 13:35:27 -0500 Subject: ecryptfs: initialize private persistent file before dereferencing pointer Ecryptfs_open dereferences a pointer to the private lower file (the one stored in the ecryptfs inode), without checking if the pointer is NULL. Right afterward, it initializes that pointer if it is NULL. Swap order of statements to first initialize. Bug discovered by Duckjin Kang. Signed-off-by: Duckjin Kang Signed-off-by: Erez Zadok Cc: Dustin Kirkland Cc: Al Viro Cc: Signed-off-by: Tyler Hicks --- fs/ecryptfs/file.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'fs/ecryptfs/file.c') diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c index 3efc7fdc3c39..dde7bb48bb5f 100644 --- a/fs/ecryptfs/file.c +++ b/fs/ecryptfs/file.c @@ -191,13 +191,6 @@ static int ecryptfs_open(struct inode *inode, struct file *file) | ECRYPTFS_ENCRYPTED); } mutex_unlock(&crypt_stat->cs_mutex); - if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_RDONLY) - && !(file->f_flags & O_RDONLY)) { - rc = -EPERM; - printk(KERN_WARNING "%s: Lower persistent file is RO; eCryptfs " - "file must hence be opened RO\n", __func__); - goto out; - } if (!ecryptfs_inode_to_private(inode)->lower_file) { rc = ecryptfs_init_persistent_file(ecryptfs_dentry); if (rc) { @@ -208,6 +201,13 @@ static int ecryptfs_open(struct inode *inode, struct file *file) goto out; } } + if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_RDONLY) + && !(file->f_flags & O_RDONLY)) { + rc = -EPERM; + printk(KERN_WARNING "%s: Lower persistent file is RO; eCryptfs " + "file must hence be opened RO\n", __func__); + goto out; + } ecryptfs_set_file_lower( file, ecryptfs_inode_to_private(inode)->lower_file); if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) { -- cgit v1.2.2 From 4aa25bcb7dac2d583f1557e2be2d0b598581da54 Mon Sep 17 00:00:00 2001 From: Julia Lawall Date: Sat, 16 Jan 2010 17:00:26 +0100 Subject: ecryptfs: Eliminate useless code The variable lower_dentry is initialized twice to the same (side effect-free) expression. Drop one initialization. A simplified version of the semantic match that finds this problem is: (http://coccinelle.lip6.fr/) // @forall@ idexpression *x; identifier f!=ERR_PTR; @@ x = f(...) ... when != x ( x = f(...,<+...x...+>,...) | * x = f(...) ) // Signed-off-by: Julia Lawall Signed-off-by: Tyler Hicks --- fs/ecryptfs/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ecryptfs/file.c') diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c index dde7bb48bb5f..678172b61be2 100644 --- a/fs/ecryptfs/file.c +++ b/fs/ecryptfs/file.c @@ -158,7 +158,7 @@ static int ecryptfs_open(struct inode *inode, struct file *file) struct dentry *ecryptfs_dentry = file->f_path.dentry; /* Private value of ecryptfs_dentry allocated in * ecryptfs_lookup() */ - struct dentry *lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); + struct dentry *lower_dentry; struct ecryptfs_file_info *file_info; mount_crypt_stat = &ecryptfs_superblock_to_private( -- cgit v1.2.2