CVS commit: src/sys/uvm

["Chuck Silvers" <chs%netbsd.org@localhost>]

Module Name:    src
Committed By:   chs
Date:           Wed Dec 21 02:28:06 UTC 2022

Modified Files:
        src/sys/uvm: uvm_swap.c

Log Message:
swap: disallow user opens of swap block device

the swap/drum block device was never intended to allow user opens,
but when the internal VOP_OPEN() in uvm_swap_init() was added
back in rev 1.135, the d_open method was changed from always-fail
to always-succeed in order to allow the new initial internal open.
this had the side effect of incorrectly allowing user opens too.
fix this by replacing the swap_bdevsw d_open with one that succeeds
for the first call but fails for all subsequent calls.

Reported-by: syzbot+90a23d2f19e5a0a302b3%syzkaller.appspotmail.com@localhost


To generate a diff of this commit:
cvs rdiff -u -r1.206 -r1.207 src/sys/uvm/uvm_swap.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.