the build (oops!): replace calls to p_trespass() and PRISON_CHECK()
with p_can(..., {P_CAN_SEE, P_CAN_DEBUG}, NULL)
o Remove volatile usage from procfs_readdir() to remove warnings
o Apply bp's CREATE fix to linprocfs, causing EROFS to be returned on
CREATE calls to procfs_lookup()
o Some further synchronization still needs to occur: only existing
access checks were replaced, to fix the build--the new ones were not
added. I'll do this later today, this is a "fix the build quickly"
commit. This means that, in the interim, some information leakage
can still occur via linprocfs when using jail or kern.ps_showallprocs
Submitted by: knu
Approved by: des
Obtained from: TrustedBSD Project
Make linux_to_bsd_sigset and linux_do_sigaction non-static.
Move linux_sigaction. linux_sigsuspend, linux_rt_sigsuspend,
linux_pause and linux_sigaltstack to MD code.
gcc's internal exit() prototypes and the (futile) hackery that we did to
try and avoid warnings. main() was renamed for similar reasons.
Remove an exit related hack from makesyscalls.sh.
to construct a path that was long enough (ie longer than
SPARE_USRSPACE bytes) and trash the stack.
Note that SPARE_USRSPACE is much smaller than MAXPATHLEN so that
the Linuxulator will now return ENAMETOOLONG even if the path
is smaller than MAXPATHLEN.
PR: 12749
is not needed since the FreeBSD native implementation switched
from TIOC{G|S}PGRP to FIO{G|S}ETOWN (kern_descrip.c rev 1.55).
PR: 16946
Submitted by: Victor Salaman <salaman@teknos.com>
the gating of system calls that cause modifications to the underlying
filesystem. The gating can be enabled by any filesystem that needs
to consistently suspend operations by adding the vop_stdgetwritemount
to their set of vnops. Once gating is enabled, the function
vfs_write_suspend stops all new write operations to a filesystem,
allows any filesystem modifying system calls already in progress
to complete, then sync's the filesystem to disk and returns. The
function vfs_write_resume allows the suspended write operations to
begin again. Gating is not added by default for all filesystems as
for SMP systems it adds two extra locks to such critical kernel
paths as the write system call. Thus, gating should only be added
as needed.
Details on the use and current status of snapshots in FFS can be
found in /sys/ufs/ffs/README.snapshot so for brevity and timelyness
is not included here. Unless and until you create a snapshot file,
these changes should have no effect on your system (famous last words).
instead of a struct iovec * array and int len. Get rid of stupidly trying
to allocate all of the memory and copyin()ing the entire iovec[], and
instead just do the proper VOP_WRITE() in ktrwrite() using a copy of
the struct uio that the syscall originally used.
This solves the DoS which could easily be performed; to work around the
DoS, one could also remove "options KTRACE" from the kernel. This is
a very strong MFC candidate for 4.1.
Found by: art@OpenBSD.org
1) while allocating a uidinfo struct malloc is called with M_WAITOK,
it's possible that while asleep another process by the same user
could have woken up earlier and inserted an entry into the uid
hash table. Having redundant entries causes inconsistancies that
we can't handle.
fix: do a non-waiting malloc, and if that fails then do a blocking
malloc, after waking up check that no one else has inserted an entry
for us already.
2) Because many checks for sbsize were done as "test then set" in a non
atomic manner it was possible to exceed the limits put up via races.
fix: instead of querying the count then setting, we just attempt to
set the count and leave it up to the function to return success or
failure.
3) The uidinfo code was inlining and repeating, lookups and insertions
and deletions needed to be in their own functions for clarity.
Reviewed by: green
doesn't. In the Linux emulation layer, ignore the fd passed when
MAP_ANON is specified.
Known application to be fixed: Xanalys/Harlequin Lispworks
Also improve debug output for mmap, now showing what the emulation
layer mapped to what (-DDEBUG).
Reviewed by: marcel
