forked from Minki/linux
9c2d205664
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> |
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.. | ||
crypto.c | ||
debug.c | ||
dentry.c | ||
ecryptfs_kernel.h | ||
file.c | ||
inode.c | ||
Kconfig | ||
keystore.c | ||
kthread.c | ||
main.c | ||
Makefile | ||
messaging.c | ||
miscdev.c | ||
mmap.c | ||
read_write.c | ||
super.c |