[v3,0/6] Clean up error handling in libvhost-user memory mapping

Message

Raphael Norwitz Jan. 17, 2022, 4:12 a.m. UTC

Hey Stefan, Marc-Andre, MST, David -

As promised here is a series cleaning up error handling in the
libvhost-user memory mapping path. Most of these cleanups are
straightforward and have been discussed on the mailing list in threads
[1] and [2].

[1] https://lore.kernel.org/qemu-devel/20211018143319.GA11006@raphael-debian-dev/
[2] https://lore.kernel.org/qemu-devel/[e-mail]/

Changes since V1:
 * Checks for a single fd vu_add_mem_reg and vu_rem_mem_reg return false
   instead of true.
 * Check for over-running max ram slots in vu_add_mem_reg returns false
   instead of true.
 * vu_rem_mem_reg unmaps all matching regions.
 * Decriment iterator variable when looping through regions in
   vu_rem_mem_reg to ensure matching regions aren’t missed.

Changes since V2:
 * Fixed FD leaks on all input validation failures
 * Added comment David suggested to explain removing duplicate regions
 * Added David’s patch to close message FDs on VHOST_USER_REM_MEM_REG
 * Expanded commit message for patches checking FD numbers
 * Fixed vmsg->size <= sizeof(vmsg->payload.memreg) validation check
 * Improved error message when a backend has no free slots
 * Improved error messages when the backend receives invalid vmsg->fd_num
   and/or vmeg->size

Dropped R-b tags due to non-trivial changes.

Thanks,
Raphael

David Hildenbrand (2):
  libvhost-user: Simplify VHOST_USER_REM_MEM_REG
  libvhost-user: fix VHOST_USER_REM_MEM_REG not closing the fd

Raphael Norwitz (4):
  libvhost-user: Add vu_rem_mem_reg input validation
  libvhost-user: Add vu_add_mem_reg input validation
  libvhost-user: prevent over-running max RAM slots
  libvhost-user: handle removal of identical regions

 subprojects/libvhost-user/libvhost-user.c | 76 ++++++++++++++++++-----
 subprojects/libvhost-user/libvhost-user.h |  2 +
 2 files changed, 61 insertions(+), 17 deletions(-)