]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
vfs, fdtable: Prevent bounds-check bypass via speculative execution
authorDan Williams <dan.j.williams@intel.com>
Tue, 30 Jan 2018 01:03:05 +0000 (17:03 -0800)
committerThomas Gleixner <tglx@linutronix.de>
Tue, 30 Jan 2018 20:54:32 +0000 (21:54 +0100)
commit56c30ba7b348b90484969054d561f711ba196507
tree6e5d8ed79763c5cbf8477f8627ae0545dacc3ff0
parent2fbd7af5af8665d18bcefae3e9700be07e22b681
vfs, fdtable: Prevent bounds-check bypass via speculative execution

'fd' is a user controlled value that is used as a data dependency to
read from the 'fdt->fd' array.  In order to avoid potential leaks of
kernel memory values, block speculative execution of the instruction
stream that could issue reads based on an invalid 'file *' returned from
__fcheck_files.

Co-developed-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727418500.33451.17392199002892248656.stgit@dwillia2-desk3.amr.corp.intel.com
include/linux/fdtable.h