cvs commit: src/sys/net bpf.c

[Robert Watson]

rwatson     2004-09-09 04:11:12 UTC

  FreeBSD src repository

  Modified files:
    sys/net              bpf.c 
  Log:
  Reformulate bpf_dettachd() to acquire the BIF_LOCK() as well as
  BPFD_LOCK() when removing a descriptor from an interface descriptor
  list.  Hold both over the operation, and do a better job at
  maintaining the invariant that you can't find partially connected
  descriptors on an active interface descriptor list.
  
  This appears to close a race that resulted in the kernel performing
  a NULL pointer dereference when BPF sessions are detached during
  heavy network activity on SMP systems.
  
  RELENG_5 candidate.
  
  Revision  Changes    Path
  1.136     +20 -11    src/sys/net/bpf.c