Tyler Hicks 9c2d205664 eCryptfs: Prevent lower dentry from going negative during unlink ... When calling vfs_unlink() on the lower dentry, d_delete() turns the dentry into a negative dentry when the d_count is 1. This eventually caused a NULL pointer deref when a read() or write() was done and the negative dentry's d_inode was dereferenced in ecryptfs_read_update_atime() or ecryptfs_getxattr(). Placing mutt's tmpdir in an eCryptfs mount is what initially triggered the oops and I was able to reproduce it with the following sequence: open("/tmp/upper/foo", O_RDWR|O_CREAT|O_EXCL|O_NOFOLLOW, 0600) = 3 link("/tmp/upper/foo", "/tmp/upper/bar") = 0 unlink("/tmp/upper/foo") = 0 open("/tmp/upper/bar", O_RDWR|O_CREAT|O_NOFOLLOW, 0600) = 4 unlink("/tmp/upper/bar") = 0 write(4, "eCryptfs test\n"..., 14 <unfinished ...> +++ killed by SIGKILL +++ https://bugs.launchpad.net/ecryptfs/+bug/387073 Reported-by: Loïc Minier <loic.minier@canonical.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com> Cc: ecryptfs-devel@lists.launchpad.net Cc: stable <stable@kernel.org> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>		2009-09-23 09:10:34 -05:00
..
crypto.c	eCryptfs: Propagate vfs_read and vfs_write return codes	2009-09-23 09:10:34 -05:00
debug.c
dentry.c
ecryptfs_kernel.h	const: mark remaining address_space_operations const	2009-09-22 07:17:24 -07:00
file.c
inode.c	eCryptfs: Prevent lower dentry from going negative during unlink	2009-09-23 09:10:34 -05:00
Kconfig	ecryptfs: improved dependency checking and reporting	2009-09-23 09:10:31 -05:00
keystore.c	eCryptfs: Validate global auth tok keys	2009-09-23 09:10:32 -05:00
kthread.c	eCryptfs: Check for O_RDONLY lower inodes when opening lower files	2009-09-23 09:10:32 -05:00
main.c	eCryptfs: Check for O_RDONLY lower inodes when opening lower files	2009-09-23 09:10:32 -05:00
Makefile
messaging.c
miscdev.c
mmap.c	eCryptfs: Propagate vfs_read and vfs_write return codes	2009-09-23 09:10:34 -05:00
read_write.c	eCryptfs: Propagate vfs_read and vfs_write return codes	2009-09-23 09:10:34 -05:00
super.c	ecryptfs: Remove unneeded locking that triggers lockdep false positives	2009-09-23 09:10:30 -05:00