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path: root/fs/ecryptfs
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2012-09-14eCryptfs: Copy up attributes of the lower target inode after renameTyler Hicks1-0/+5
After calling into the lower filesystem to do a rename, the lower target inode's attributes were not copied up to the eCryptfs target inode. This resulted in the eCryptfs target inode staying around, rather than being evicted, because i_nlink was not updated for the eCryptfs inode. This also meant that eCryptfs didn't do the final iput() on the lower target inode so it stayed around, as well. This would result in a failure to free up space occupied by the target file in the rename() operation. Both target inodes would eventually be evicted when the eCryptfs filesystem was unmounted. This patch calls fsstack_copy_attr_all() after the lower filesystem does its ->rename() so that important inode attributes, such as i_nlink, are updated at the eCryptfs layer. ecryptfs_evict_inode() is now called and eCryptfs can drop its final reference on the lower inode. http://launchpad.net/bugs/561129 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Tested-by: Colin Ian King <colin.king@canonical.com> Cc: <stable@vger.kernel.org> [2.6.39+]
2012-09-14eCryptfs: Call lower ->flush() from ecryptfs_flush()Tyler Hicks1-2/+8
Since eCryptfs only calls fput() on the lower file in ecryptfs_release(), eCryptfs should call the lower filesystem's ->flush() from ecryptfs_flush(). If the lower filesystem implements ->flush(), then eCryptfs should try to flush out any dirty pages prior to calling the lower ->flush(). If the lower filesystem does not implement ->flush(), then eCryptfs has no need to do anything in ecryptfs_flush() since dirty pages are now written out to the lower filesystem in ecryptfs_release(). Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-09-14eCryptfs: Write out all dirty pages just before releasing the lower fileTyler Hicks1-0/+1
Fixes a regression caused by: 821f749 eCryptfs: Revert to a writethrough cache model That patch reverted some code (specifically, 32001d6f) that was necessary to properly handle open() -> mmap() -> close() -> dirty pages -> munmap(), because the lower file could be closed before the dirty pages are written out. Rather than reapplying 32001d6f, this approach is a better way of ensuring that the lower file is still open in order to handle writing out the dirty pages. It is called from ecryptfs_release(), while we have a lock on the lower file pointer, just before the lower file gets the final fput() and we overwrite the pointer. https://launchpad.net/bugs/1047261 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Artemy Tregubenko <me@arty.name> Tested-by: Artemy Tregubenko <me@arty.name> Tested-by: Colin Ian King <colin.king@canonical.com>
2012-08-02Merge tag 'ecryptfs-3.6-rc1-fixes' of ↵Linus Torvalds7-316/+158
git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs Pull ecryptfs fixes from Tyler Hicks: - Fixes a bug when the lower filesystem mount options include 'acl', but the eCryptfs mount options do not - Cleanups in the messaging code - Better handling of empty files in the lower filesystem to improve usability. Failed file creations are now cleaned up and empty lower files are converted into eCryptfs during open(). - The write-through cache changes are being reverted due to bugs that are not easy to fix. Stability outweighs the performance enhancements here. - Improvement to the mount code to catch unsupported ciphers specified in the mount options * tag 'ecryptfs-3.6-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs: eCryptfs: check for eCryptfs cipher support at mount eCryptfs: Revert to a writethrough cache model eCryptfs: Initialize empty lower files when opening them eCryptfs: Unlink lower inode when ecryptfs_create() fails eCryptfs: Make all miscdev functions use daemon ptr in file private_data eCryptfs: Remove unused messaging declarations and function eCryptfs: Copy up POSIX ACL and read-only flags from lower mount
2012-07-29ecryptfs_lookup_interpose(): allocate dentry_info firstAl Viro1-7/+6
less work on failure that way Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-29sanitize ecryptfs_lookup()Al Viro1-13/+4
* ->lookup() never gets hit with . or .. * dentry it gets is unhashed, so unless we had gone and hashed it ourselves, there's no need to d_drop() the sucker. * wrong name printed in one of the printks (NULL, in fact) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-23switch dentry_open() to struct path, make it grab references itselfAl Viro1-13/+8
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-23ecryptfs: don't reinvent the wheels, please - use struct completionAl Viro3-65/+26
... and keep the sodding requests on stack - they are small enough. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-23don't expose I_NEW inodes via dentry->d_inodeAl Viro1-1/+1
d_instantiate(dentry, inode); unlock_new_inode(inode); is a bad idea; do it the other way round... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14VFS: Pass mount flags to sget()David Howells1-2/+1
Pass mount flags to sget() so that it can use them in initialising a new superblock before the set function is called. They could also be passed to the compare function. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14don't pass nameidata * to vfs_create()Al Viro1-1/+1
all we want is a boolean flag, same as the method gets now Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14don't pass nameidata to ->create()Al Viro1-2/+1
boolean "does it have to be exclusive?" flag is passed instead; Local filesystem should just ignore it - the object is guaranteed not to be there yet. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14stop passing nameidata to ->lookup()Al Viro1-1/+1
Just the flags; only NFS cares even about that, but there are legitimate uses for such argument. And getting rid of that completely would require splitting ->lookup() into a couple of methods (at least), so let's leave that alone for now... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14stop passing nameidata * to ->d_revalidate()Al Viro1-16/+4
Just the lookup flags. Die, bastard, die... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14eCryptfs: check for eCryptfs cipher support at mountTim Sally1-0/+13
The issue occurs when eCryptfs is mounted with a cipher supported by the crypto subsystem but not by eCryptfs. The mount succeeds and an error does not occur until a write. This change checks for eCryptfs cipher support at mount time. Resolves Launchpad issue #338914, reported by Tyler Hicks in 03/2009. https://bugs.launchpad.net/ecryptfs/+bug/338914 Signed-off-by: Tim Sally <tsally@atomicpeace.com> Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-07-14eCryptfs: Revert to a writethrough cache modelTyler Hicks3-63/+15
A change was made about a year ago to get eCryptfs to better utilize its page cache during writes. The idea was to do the page encryption operations during page writeback, rather than doing them when initially writing into the page cache, to reduce the number of page encryption operations during sequential writes. This meant that the encrypted page would only be written to the lower filesystem during page writeback, which was a change from how eCryptfs had previously wrote to the lower filesystem in ecryptfs_write_end(). The change caused a few eCryptfs-internal bugs that were shook out. Unfortunately, more grave side effects have been identified that will force changes outside of eCryptfs. Because the lower filesystem isn't consulted until page writeback, eCryptfs has no way to pass lower write errors (ENOSPC, mainly) back to userspace. Additionaly, it was reported that quotas could be bypassed because of the way eCryptfs may sometimes open the lower filesystem using a privileged kthread. It would be nice to resolve the latest issues, but it is best if the eCryptfs commits be reverted to the old behavior in the meantime. This reverts: 32001d6f "eCryptfs: Flush file in vma close" 5be79de2 "eCryptfs: Flush dirty pages in setattr" 57db4e8d "ecryptfs: modify write path to encrypt page in writepage" Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Tested-by: Colin King <colin.king@canonical.com> Cc: Colin King <colin.king@canonical.com> Cc: Thieu Le <thieule@google.com>
2012-07-08eCryptfs: Initialize empty lower files when opening themTyler Hicks3-28/+49
Historically, eCryptfs has only initialized lower files in the ecryptfs_create() path. Lower file initialization is the act of writing the cryptographic metadata from the inode's crypt_stat to the header of the file. The ecryptfs_open() path already expects that metadata to be in the header of the file. A number of users have reported empty lower files in beneath their eCryptfs mounts. Most of the causes for those empty files being left around have been addressed, but the presence of empty files causes problems due to the lack of proper cryptographic metadata. To transparently solve this problem, this patch initializes empty lower files in the ecryptfs_open() error path. If the metadata is unreadable due to the lower inode size being 0, plaintext passthrough support is not in use, and the metadata is stored in the header of the file (as opposed to the user.ecryptfs extended attribute), the lower file will be initialized. The number of nested conditionals in ecryptfs_open() was getting out of hand, so a helper function was created. To avoid the same nested conditional problem, the conditional logic was reversed inside of the helper function. https://launchpad.net/bugs/911507 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Cc: John Johansen <john.johansen@canonical.com> Cc: Colin Ian King <colin.king@canonical.com>
2012-07-08eCryptfs: Unlink lower inode when ecryptfs_create() failsTyler Hicks1-23/+32
ecryptfs_create() creates a lower inode, allocates an eCryptfs inode, initializes the eCryptfs inode and cryptographic metadata attached to the inode, and then writes the metadata to the header of the file. If an error was to occur after the lower inode was created, an empty lower file would be left in the lower filesystem. This is a problem because ecryptfs_open() refuses to open any lower files which do not have the appropriate metadata in the file header. This patch properly unlinks the lower inode when an error occurs in the later stages of ecryptfs_create(), reducing the chance that an empty lower file will be left in the lower filesystem. https://launchpad.net/bugs/872905 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Cc: John Johansen <john.johansen@canonical.com> Cc: Colin Ian King <colin.king@canonical.com>
2012-07-08eCryptfs: Make all miscdev functions use daemon ptr in file private_dataTyler Hicks3-172/+47
Now that a pointer to a valid struct ecryptfs_daemon is stored in the private_data of an opened /dev/ecryptfs file, the remaining miscdev functions can utilize the pointer rather than looking up the ecryptfs_daemon at the beginning of each operation. The security model of /dev/ecryptfs is simplified a little bit with this patch. Upon opening /dev/ecryptfs, a per-user ecryptfs_daemon is registered. Another daemon cannot be registered for that user until the last file reference is released. During the lifetime of the ecryptfs_daemon, access checks are not performed on the /dev/ecryptfs operations because it is assumed that the application securely handles the opened file descriptor and does not unintentionally leak it to processes that are not trusted. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Cc: Sasha Levin <levinsasha928@gmail.com>
2012-07-08eCryptfs: Remove unused messaging declarations and functionTyler Hicks2-37/+0
These are no longer needed. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Cc: Sasha Levin <levinsasha928@gmail.com>
2012-07-08eCryptfs: Copy up POSIX ACL and read-only flags from lower mountTyler Hicks1-1/+9
When the eCryptfs mount options do not include '-o acl', but the lower filesystem's mount options do include 'acl', the MS_POSIXACL flag is not flipped on in the eCryptfs super block flags. This flag is what the VFS checks in do_last() when deciding if the current umask should be applied to a newly created inode's mode or not. When a default POSIX ACL mask is set on a directory, the current umask is incorrectly applied to new inodes created in the directory. This patch ignores the MS_POSIXACL flag passed into ecryptfs_mount() and sets the flag on the eCryptfs super block depending on the flag's presence on the lower super block. Additionally, it is incorrect to allow a writeable eCryptfs mount on top of a read-only lower mount. This missing check did not allow writes to the read-only lower mount because permissions checks are still performed on the lower filesystem's objects but it is best to simply not allow a rw mount on top of ro mount. However, a ro eCryptfs mount on top of a rw mount is valid and still allowed. https://launchpad.net/bugs/1009207 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Stefan Beller <stefanbeller@googlemail.com> Cc: John Johansen <john.johansen@canonical.com>
2012-07-07eCryptfs: Gracefully refuse miscdev file ops on inherited/passed filesTyler Hicks1-7/+16
File operations on /dev/ecryptfs would BUG() when the operations were performed by processes other than the process that originally opened the file. This could happen with open files inherited after fork() or file descriptors passed through IPC mechanisms. Rather than calling BUG(), an error code can be safely returned in most situations. In ecryptfs_miscdev_release(), eCryptfs still needs to handle the release even if the last file reference is being held by a process that didn't originally open the file. ecryptfs_find_daemon_by_euid() will not be successful, so a pointer to the daemon is stored in the file's private_data. The private_data pointer is initialized when the miscdev file is opened and only used when the file is released. https://launchpad.net/bugs/994247 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Sasha Levin <levinsasha928@gmail.com> Tested-by: Sasha Levin <levinsasha928@gmail.com>
2012-07-04eCryptfs: Fix lockdep warning in miscdev operationsTyler Hicks1-12/+13
Don't grab the daemon mutex while holding the message context mutex. Addresses this lockdep warning: ecryptfsd/2141 is trying to acquire lock: (&ecryptfs_msg_ctx_arr[i].mux){+.+.+.}, at: [<ffffffffa029c213>] ecryptfs_miscdev_read+0x143/0x470 [ecryptfs] but task is already holding lock: (&(*daemon)->mux){+.+...}, at: [<ffffffffa029c2ec>] ecryptfs_miscdev_read+0x21c/0x470 [ecryptfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&(*daemon)->mux){+.+...}: [<ffffffff810a3b8d>] lock_acquire+0x9d/0x220 [<ffffffff8151c6da>] __mutex_lock_common+0x5a/0x4b0 [<ffffffff8151cc64>] mutex_lock_nested+0x44/0x50 [<ffffffffa029c5d7>] ecryptfs_send_miscdev+0x97/0x120 [ecryptfs] [<ffffffffa029b744>] ecryptfs_send_message+0x134/0x1e0 [ecryptfs] [<ffffffffa029a24e>] ecryptfs_generate_key_packet_set+0x2fe/0xa80 [ecryptfs] [<ffffffffa02960f8>] ecryptfs_write_metadata+0x108/0x250 [ecryptfs] [<ffffffffa0290f80>] ecryptfs_create+0x130/0x250 [ecryptfs] [<ffffffff811963a4>] vfs_create+0xb4/0x120 [<ffffffff81197865>] do_last+0x8c5/0xa10 [<ffffffff811998f9>] path_openat+0xd9/0x460 [<ffffffff81199da2>] do_filp_open+0x42/0xa0 [<ffffffff81187998>] do_sys_open+0xf8/0x1d0 [<ffffffff81187a91>] sys_open+0x21/0x30 [<ffffffff81527d69>] system_call_fastpath+0x16/0x1b -> #0 (&ecryptfs_msg_ctx_arr[i].mux){+.+.+.}: [<ffffffff810a3418>] __lock_acquire+0x1bf8/0x1c50 [<ffffffff810a3b8d>] lock_acquire+0x9d/0x220 [<ffffffff8151c6da>] __mutex_lock_common+0x5a/0x4b0 [<ffffffff8151cc64>] mutex_lock_nested+0x44/0x50 [<ffffffffa029c213>] ecryptfs_miscdev_read+0x143/0x470 [ecryptfs] [<ffffffff811887d3>] vfs_read+0xb3/0x180 [<ffffffff811888ed>] sys_read+0x4d/0x90 [<ffffffff81527d69>] system_call_fastpath+0x16/0x1b Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-07-04eCryptfs: Properly check for O_RDONLY flag before doing privileged openTyler Hicks1-1/+1
If the first attempt at opening the lower file read/write fails, eCryptfs will retry using a privileged kthread. However, the privileged retry should not happen if the lower file's inode is read-only because a read/write open will still be unsuccessful. The check for determining if the open should be retried was intended to be based on the access mode of the lower file's open flags being O_RDONLY, but the check was incorrectly performed. This would cause the open to be retried by the privileged kthread, resulting in a second failed open of the lower file. This patch corrects the check to determine if the open request should be handled by the privileged kthread. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Dan Carpenter <dan.carpenter@oracle.com>
2012-05-30get rid of pointless allocations and copying in ecryptfs_follow_link()Al Viro1-39/+9
switch to generic_readlink(), while we are at it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-28Merge tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linuxLinus Torvalds1-1/+1
Pull writeback tree from Wu Fengguang: "Mainly from Jan Kara to avoid iput() in the flusher threads." * tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Avoid iput() from flusher thread vfs: Rename end_writeback() to clear_inode() vfs: Move waiting for inode writeback from end_writeback() to evict_inode() writeback: Refactor writeback_single_inode() writeback: Remove wb->list_lock from writeback_single_inode() writeback: Separate inode requeueing after writeback writeback: Move I_DIRTY_PAGES handling writeback: Move requeueing when I_SYNC set to writeback_sb_inodes() writeback: Move clearing of I_SYNC into inode_sync_complete() writeback: initialize global_dirty_limit fs: remove 8 bytes of padding from struct writeback_control on 64 bit builds mm: page-writeback.c: local functions should not be exposed globally
2012-05-06vfs: Rename end_writeback() to clear_inode()Jan Kara1-1/+1
After we moved inode_sync_wait() from end_writeback() it doesn't make sense to call the function end_writeback() anymore. Rename it to clear_inode() which well says what the function really does - set I_CLEAR flag. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
2012-04-08userns: Use cred->user_ns instead of cred->user->user_nsEric W. Biederman1-1/+1
Optimize performance and prepare for the removal of the user_ns reference from user_struct. Remove the slow long walk through cred->user->user_ns and instead go straight to cred->user_ns. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-03-21ecryptfs: make register_filesystem() the last potential failure exitAl Viro1-8/+8
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-21switch touch_atime to struct pathAl Viro1-5/+4
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-21switch open-coded instances of d_make_root() to new helperAl Viro1-2/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-21ecryptfs: don't bother with ->drop_inode()Al Viro1-1/+0
generic_drop_inode() is the default Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-02-29ecryptfs: fix printk format warning for size_tRandy Dunlap1-1/+1
Fix printk format warning (from Linus's suggestion): on i386: fs/ecryptfs/miscdev.c:433:38: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'unsigned int' and on x86_64: fs/ecryptfs/miscdev.c:433:38: warning: format '%u' expects type 'unsigned int', but argument 4 has type 'long unsigned int' Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Dustin Kirkland <dustin.kirkland@gazzang.com> Cc: ecryptfs@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-17ecryptfs: remove the second argument of k[un]map_atomic()Cong Wang2-4/+4
Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-02-17eCryptfs: Copy up lower inode attrs after setting lower xattrTyler Hicks1-0/+2
After passing through a ->setxattr() call, eCryptfs needs to copy the inode attributes from the lower inode to the eCryptfs inode, as they may have changed in the lower filesystem's ->setxattr() path. One example is if an extended attribute containing a POSIX Access Control List is being set. The new ACL may cause the lower filesystem to modify the mode of the lower inode and the eCryptfs inode would need to be updated to reflect the new mode. https://launchpad.net/bugs/926292 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Sebastien Bacher <seb128@ubuntu.com> Cc: John Johansen <john.johansen@canonical.com> Cc: <stable@vger.kernel.org>
2012-02-17eCryptfs: Improve statfs reportingTyler Hicks4-14/+83
statfs() calls on eCryptfs files returned the wrong filesystem type and, when using filename encryption, the wrong maximum filename length. If mount-wide filename encryption is enabled, the cipher block size and the lower filesystem's max filename length will determine the max eCryptfs filename length. Pre-tested, known good lengths are used when the lower filesystem's namelen is 255 and a cipher with 8 or 16 byte block sizes is used. In other, less common cases, we fall back to a safe rounded-down estimate when determining the eCryptfs namelen. https://launchpad.net/bugs/885744 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: John Johansen <john.johansen@canonical.com>
2012-01-26eCryptfs: move misleading function commentsLi Wang1-4/+4
The data encryption was moved from ecryptfs_write_end into ecryptfs_writepage, this patch moves the corresponding function comments to be consistent with the modification. Signed-off-by: Li Wang <liwang@nudt.edu.cn> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-26eCryptfs: Fix oops when printing debug info in extent crypto functionsTyler Hicks1-40/+0
If pages passed to the eCryptfs extent-based crypto functions are not mapped and the module parameter ecryptfs_verbosity=1 was specified at loading time, a NULL pointer dereference will occur. Note that this wouldn't happen on a production system, as you wouldn't pass ecryptfs_verbosity=1 on a production system. It leaks private information to the system logs and is for debugging only. The debugging info printed in these messages is no longer very useful and rather than doing a kmap() in these debugging paths, it will be better to simply remove the debugging paths completely. https://launchpad.net/bugs/913651 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Daniel DeFreez Cc: <stable@vger.kernel.org>
2012-01-26eCryptfs: Remove unused ecryptfs_read()Tyler Hicks1-73/+0
ecryptfs_read() has been ifdef'ed out for years now and it was apparently unused before then. It is time to get rid of it for good. Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-01-26eCryptfs: Check inode changes in setattrTyler Hicks1-12/+36
Most filesystems call inode_change_ok() very early in ->setattr(), but eCryptfs didn't call it at all. It allowed the lower filesystem to make the call in its ->setattr() function. Then, eCryptfs would copy the appropriate inode attributes from the lower inode to the eCryptfs inode. This patch changes that and actually calls inode_change_ok() on the eCryptfs inode, fairly early in ecryptfs_setattr(). Ideally, the call would happen earlier in ecryptfs_setattr(), but there are some possible inode initialization steps that must happen first. Since the call was already being made on the lower inode, the change in functionality should be minimal, except for the case of a file extending truncate call. In that case, inode_newsize_ok() was never being called on the eCryptfs inode. Rather than inode_newsize_ok() catching maximum file size errors early on, eCryptfs would encrypt zeroed pages and write them to the lower filesystem until the lower filesystem's write path caught the error in generic_write_checks(). This patch introduces a new function, called ecryptfs_inode_newsize_ok(), which checks if the new lower file size is within the appropriate limits when the truncate operation will be growing the lower file. In summary this change prevents eCryptfs truncate operations (and the resulting page encryptions), which would exceed the lower filesystem limits or FSIZE rlimits, from ever starting. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reviewed-by: Li Wang <liwang@nudt.edu.cn> Cc: <stable@vger.kernel.org>
2012-01-26eCryptfs: Make truncate path killableTyler Hicks1-5/+14
ecryptfs_write() handles the truncation of eCryptfs inodes. It grabs a page, zeroes out the appropriate portions, and then encrypts the page before writing it to the lower filesystem. It was unkillable and due to the lack of sparse file support could result in tying up a large portion of system resources, while encrypting pages of zeros, with no way for the truncate operation to be stopped from userspace. This patch adds the ability for ecryptfs_write() to detect a pending fatal signal and return as gracefully as possible. The intent is to leave the lower file in a useable state, while still allowing a user to break out of the encryption loop. If a pending fatal signal is detected, the eCryptfs inode size is updated to reflect the modified inode size and then -EINTR is returned. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Cc: <stable@vger.kernel.org>
2012-01-26eCryptfs: Infinite loop due to overflow in ecryptfs_write()Li Wang1-2/+2
ecryptfs_write() can enter an infinite loop when truncating a file to a size larger than 4G. This only happens on architectures where size_t is represented by 32 bits. This was caused by a size_t overflow due to it incorrectly being used to store the result of a calculation which uses potentially large values of type loff_t. [tyhicks@canonical.com: rewrite subject and commit message] Signed-off-by: Li Wang <liwang@nudt.edu.cn> Signed-off-by: Yunchuan Wen <wenyunchuan@kylinos.com.cn> Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-01-26eCryptfs: Replace miscdev read/write magic numbersTyler Hicks3-41/+55
ecryptfs_miscdev_read() and ecryptfs_miscdev_write() contained many magic numbers for specifying packet header field sizes and offsets. This patch defines those values and replaces the magic values. Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-01-26eCryptfs: Report errors in writes to /dev/ecryptfsTyler Hicks1-11/+13
Errors in writes to /dev/ecryptfs were being incorrectly reported by returning 0 or the value of the original write count. This patch clears up the return code assignment in error paths. Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-01-26eCryptfs: Sanitize write counts of /dev/ecryptfsTyler Hicks1-18/+38
A malicious count value specified when writing to /dev/ecryptfs may result in a a very large kernel memory allocation. This patch peeks at the specified packet payload size, adds that to the size of the packet headers and compares the result with the write count value. The resulting maximum memory allocation size is approximately 532 bytes. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Sasha Levin <levinsasha928@gmail.com> Cc: <stable@vger.kernel.org>
2012-01-26ecryptfs: Remove unnecessary variable initializationTim Gardner1-2/+3
Removes unneeded variable initialization in ecryptfs_read_metadata(). Also adds a small comment to help explain metadata reading logic. [tyhicks@canonical.com: Pulled out of for-stable patch and wrote commit msg] Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-01-26ecryptfs: Improve metadata read failure loggingTim Gardner1-3/+6
Print inode on metadata read failure. The only real way of dealing with metadata read failures is to delete the underlying file system file. Having the inode allows one to 'find . -inum INODE`. [tyhicks@canonical.com: Removed some minor not-for-stable parts] Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2012-01-07vfs: switch ->show_options() to struct dentry *Al Viro1-2/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-04fs: propagate umode_t, misc bitsAl Viro1-1/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-04kill ecryptfs_create_underlying_file()Al Viro1-20/+1
it's a just a wrapper for vfs_create() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>