linux/fs/ecryptfs, branch v3.2.4

eCryptfs: Fix oops when printing debug info in extent crypto functions

2012-02-03T17:21:24Z

commit 58ded24f0fcb85bddb665baba75892f6ad0f4b8a upstream. 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 Signed-off-by: Greg Kroah-Hartman

eCryptfs: Check inode changes in setattr

2012-02-03T17:21:24Z

commit a261a03904849c3df50bd0300efb7fb3f865137d upstream. 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 Reviewed-by: Li Wang Signed-off-by: Greg Kroah-Hartman

eCryptfs: Make truncate path killable

2012-02-03T17:21:23Z

commit 5e6f0d769017cc49207ef56996e42363ec26c1f0 upstream. 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 Signed-off-by: Greg Kroah-Hartman

ecryptfs: Improve metadata read failure logging

2012-02-03T17:21:23Z

commit 30373dc0c87ffef68d5628e77d56ffb1fa22e1ee upstream. 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 Reviewed-by: Kees Cook Signed-off-by: Tyler Hicks Signed-off-by: Greg Kroah-Hartman

eCryptfs: Sanitize write counts of /dev/ecryptfs

2012-02-03T17:21:22Z

commit db10e556518eb9d21ee92ff944530d84349684f4 upstream. 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 Reported-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

eCryptfs: Extend array bounds for all filename chars

2011-11-23T21:43:53Z

From mhalcrow's original commit message: Characters with ASCII values greater than the size of filename_rev_map[] are valid filename characters. ecryptfs_decode_from_filename() will access kernel memory beyond that array, and ecryptfs_parse_tag_70_packet() will then decrypt those characters. The attacker, using the FNEK of the crafted file, can then re-encrypt the characters to reveal the kernel memory past the end of the filename_rev_map[] array. I expect low security impact since this array is statically allocated in the text area, and the amount of memory past the array that is accessible is limited by the largest possible ASCII filename character. This patch solves the issue reported by mhalcrow but with an implementation suggested by Linus to simply extend the length of filename_rev_map[] to 256. Characters greater than 0x7A are mapped to 0x00, which is how invalid characters less than 0x7A were previously being handled. Signed-off-by: Tyler Hicks Reported-by: Michael Halcrow Cc: stable@kernel.org

eCryptfs: Flush file in vma close

2011-11-23T21:40:09Z

Dirty pages weren't being written back when an mmap'ed eCryptfs file was closed before the mapping was unmapped. Since f_ops->flush() is not called by the munmap() path, the lower file was simply being released. This patch flushes the eCryptfs file in the vm_ops->close() path. https://launchpad.net/bugs/870326 Signed-off-by: Tyler Hicks Cc: stable@kernel.org [2.6.39+]

eCryptfs: Prevent file create race condition

2011-11-23T21:39:38Z

The file creation path prematurely called d_instantiate() and unlock_new_inode() before the eCryptfs inode info was fully allocated and initialized and before the eCryptfs metadata was written to the lower file. This could result in race conditions in subsequent file and inode operations leading to unexpected error conditions or a null pointer dereference while attempting to use the unallocated memory. https://launchpad.net/bugs/813146 Signed-off-by: Tyler Hicks Cc: stable@kernel.org

filesystems: add set_nlink()

2011-11-02T11:53:43Z

Replace remaining direct i_nlink updates with a new set_nlink() updater function. Signed-off-by: Miklos Szeredi Tested-by: Toshiyuki Okajima Signed-off-by: Christoph Hellwig

treewide: use printf not attribute__((format(printf,...)))

2011-11-01T00:30:54Z

Standardize the style for compiler based printf format verification. Standardized the location of __printf too. Done via script and a little typing. $ grep -rPl --include=*.[ch] -w "__attribute__" * | \ grep -vP "^(tools|scripts|include/linux/compiler-gcc.h)" | \ xargs perl -n -i -e 'local $/; while (<>) { s/\b__attribute__\s*$\s*\(\s*format\s*\(\s*printf\s*,\s*(.+)\s*,\s*(.+)\s*$\s*\)\s*\)/__printf($1, $2)/g ; print; }' [akpm@linux-foundation.org: revert arch bits] Signed-off-by: Joe Perches Cc: "Kirill A. Shutemov" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds