group file. Because of the way the group sorting works while printing
out the new file it's not possible at this time to restore comments
in other locations, but at least they won't just disappear altogether.
VOP_BWRITE() was a hack which made it possible for NFS client
side to use struct buf with non-bio backing.
This patch takes a more general approach and adds a bp->b_op
vector where more methods can be added.
The success of this patch depends on bp->b_op being initialized
all relevant places for some value of "relevant" which is not
easy to determine. For now the buffers have grown a b_magic
element which will make such issues a tiny bit easier to debug.
arguments where the format string is obtained from user data, or
otherwise difficult to verify statically.
Example usage:
printf(fmtcheck(user_format, standard_format), arg1, arg2);
checks the format string user_format for consistency (same number/order/
type of format operators) with standard_format. If they differ,
standard_format is used instead to avoid potential crashes or security
violations.
Obtained from: NetBSD
Reviewed by: -arch
sized blocks. To enable this option, use: `sysctl -w debug.bigcgs=1'.
Add debugging option to disable background writes of cylinder
groups. To enable this option, use: `sysctl -w debug.dobkgrdwrite=0'.
These debugging options should be tried on systems that are panicing
with corrupted cylinder group maps to see if it makes the problem
go away. The set of panics in question are:
ffs_clusteralloc: map mismatch
ffs_nodealloccg: map corrupted
ffs_nodealloccg: block not in map
ffs_alloccg: map corrupted
ffs_alloccg: block not in map
ffs_alloccgblk: cyl groups corrupted
ffs_alloccgblk: can't find blk in cyl
ffs_checkblk: partially free fragment
The following panics are less likely to be related to this problem,
but might be helped by these debugging options:
ffs_valloc: dup alloc
ffs_blkfree: freeing free block
ffs_blkfree: freeing free frag
ffs_vfree: freeing free inode
If you try these options, please report whether they helped reduce your
bitmap corruption panics to Kirk McKusick at <mckusick@mckusick.com>
and to Matt Dillon <dillon@earth.backplane.com>.
ACL_USER_OBJ and ACL_GROUP_OBJ fields, believing that modification of the
access ACL could be used by privileged processes to change file/directory
ownership. In fact, this is incorrect; ACL_*_OBJ (+ ACL_MASK and
ACL_OTHER) should have undefined ae_id fields; this commit attempts
to correct that misunderstanding.
o Modify arguments to vaccess_acl_posix1e() to accept the uid and gid
associated with the vnode, as those can no longer be extracted from
the ACL passed as an argument. Perform all comparisons against
the passed arguments. This actually has the effect of simplifying
a number of components of this call, as well as reducing the indent
level, but now seperates handling of ACL_GROUP_OBJ from ACL_GROUP.
o Modify acl_posix1e_check() to return EINVAL if the ae_id field of
any of the ACL_{USER_OBJ,GROUP_OBJ,MASK,OTHER} entries is a value
other than ACL_UNDEFINED_ID. As a temporary work-around to allow
clean upgrades, set the ae_id field to ACL_UNDEFINED_ID before
each check so that this cannot cause a failure in the short term
(this work-around will be removed when the userland libraries and
utilities are updated to take this change into account).
o Modify ufs_sync_acl_from_inode() so that it forces
ACL_{USER_OBJ,GROUP_OBJ,MASK,OTHER} ae_id fields to ACL_UNDEFINED_ID
when synchronizing the ACL from the inode.
o Modify ufs_sync_inode_from_acl to not propagate uid and gid
information to the inode from the ACL during ACL update. Also
modify the masking of permission bits that may be set from
ALLPERMS to (S_IRWXU|S_IRWXG|S_IRWXO), as ACLs currently do not
carry none-ACCESSPERMS (S_ISUID, S_ISGID, S_ISTXT).
o Modify ufs_getacl() so that when it emulates an access ACL from
the inode, it initializes the ae_id fields to ACL_UNDEFINED_ID.
o Clean up ufs_setacl() substantially since it is no longer possible
to perform chown/chgrp operations using vop_setacl(), so all the
access control for that can be eliminated.
o Modify ufs_access() so that it passes owner uid and gid information
into vaccess_acl_posix1e().
Pointed out by: jedger
Obtained from: TrustedBSD Project
panic_cpu shared variable. I used a simple atomic operation here instead
of a spin lock as it seemed to be excessive overhead. Also, this can avoid
recursive panics if, for example, witness is broken.
can happen if witness runs out of resources during initialization or if
witness_skipspin is enabled.
Sleuthing by: Peter Jeremy <peter.jeremy@alcatel.com.au>
Limit the "pathname" glob to one item, as that is what all users of it
are expecting, except for LIST.
Always glob, instead of when the first character is a ~. For example,
if you had directories ~/x1, and ~/x2, then "cwd x[1]" would fail, but
"cwd ~/x[1]" would work since it was globbed due to the ~ character.
Also, "cwd ~/x[12]" used to arbitarily work as it used the first
expansion (ie: x1) without an error. Make it return '550 ambiguous'
instead of '550 not found' so that the user can see the difference.
For LIST, just use the user supplied string as the popen does the glob.
Problem noticed by: Ajay Mittal <amittal@iprg.nokia.com>
"inside" of locked regions. That is, an acquire atomic operation will
always enforce a memory barrier after the atomic operation and a release
operation will always enforce a memory barrier before the atomic
operation.
- Explicitly use 'mb' instead of 'wmb' in release atomic operations. The
'wmb' memory barrier is not strong enough to guarantee coherence with
other processors. This is effectively a nop since alpha_wmb() actually
performs a 'mb' and not a 'wmb', but I wanted the code to be more
correct since at some point in the future alpha_wmb()'s implementation
may switch to being a real 'wmb'.
we should call ast(). This allows us to branch to a separate Lkernelret
label so we can fixup the saved t7 register in the trapframe. Otherwise
we can run into a problem on SMP systems where a process is interrupted by
a trap or interrupt on one CPU, migrates to another CPU, and then returns
with the t7 in the stack clobbering the CPU's t7. As a result, two CPU's
would both point to the same per-CPU data and things would go downhill from
there.
Sleuthing help by: gallatin
- Add a new ddb command: 'show pcpu' similar to the i386 command added
recently. By default it displays the current CPU's info, but an optional
argument can specify the logical ID of a specific CPU to examine.
1) Set the FS_NEEDSFSCK flag when unexpected problems are encountered.
2) Clear the FS_NEEDSFSCK flag after a successful foreground cleanup.
3) Refuse to run in background when the FS_NEEDSFSCK flag is set.
4) Avoid taking and removing a snapshot when the filesystem is already clean.
5) Properly implement the force cleaning (-f) flag when in preen mode.
Note that you need to have revision 1.21 (date: 2001/04/14 05:26:28) of
fs.h installed in <ufs/ffs/fs.h> defining FS_NEEDSFSCK for this to compile.
bcopy would go off the end of the array by two elements, which sometimes
causes a panic if it happens to cross into a page that isn't mapped.
Submitted by: gibbs
Reviewed by: peter
