linux-stable.git/net/sunrpc/cache.c, branch v3.14.78

sunrpc/cache: drop reference when sunrpc_cache_pipe_upcall() detects a race

2016-05-04T21:51:26+00:00

commit a6ab1e8126d205238defbb55d23661a3a5c6a0d8 upstream.

sunrpc_cache_pipe_upcall() can detect a race if CACHE_PENDING is no longer
set.  In this case it aborts the queuing of the upcall.
However it has already taken a new counted reference on "h" and
doesn't "put" it, even though it frees the data structure holding the reference.

So let's delay the "cache_get" until we know we need it.

Fixes: f9e1aedc6c79 ("sunrpc/cache: remove races with queuing an upcall.")
Signed-off-by: NeilBrown 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

sunrpc/cache: fix off-by-one in qword_get()

2016-03-03T23:06:53+00:00

commit b7052cd7bcf3c1478796e93e3dff2b44c9e82943 upstream.

The qword_get() function NUL-terminates its output buffer.  If the input
string is in hex format \xXXXX... and the same length as the output
buffer, there is an off-by-one:

  int qword_get(char **bpp, char *dest, int bufsize)
  {
      ...
      while (len < bufsize) {
          ...
          *dest++ = (h << 4) | l;
          len++;
      }
      ...
      *dest = '\0';
      return len;
  }

This patch ensures the NUL terminator doesn't fall outside the output
buffer.

Signed-off-by: Stefan Hajnoczi 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

sunrpc: fix braino in ->poll()

2015-03-18T12:31:31+00:00

commit 1711fd9addf214823b993468567cab1f8254fc51 upstream.

POLL_OUT isn't what callers of ->poll() are expecting to see; it's
actually __SI_POLL | 2 and it's a siginfo code, not a poll bitmap
bit...

Signed-off-by: Al Viro 
Cc: Bruce Fields 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'for-3.14' of git://linux-nfs.org/~bfields/linux

2014-01-30T18:18:43+00:00

Pull nfsd updates from Bruce Fields:
 - Handle some loose ends from the vfs read delegation support.
   (For example nfsd can stop breaking leases on its own in a
    fewer places where it can now depend on the vfs to.)
 - Make life a little easier for NFSv4-only configurations
   (thanks to Kinglong Mee).
 - Fix some gss-proxy problems (thanks Jeff Layton).
 - miscellaneous bug fixes and cleanup

* 'for-3.14' of git://linux-nfs.org/~bfields/linux: (38 commits)
  nfsd: consider CLAIM_FH when handing out delegation
  nfsd4: fix delegation-unlink/rename race
  nfsd4: delay setting current_fh in open
  nfsd4: minor nfs4_setlease cleanup
  gss_krb5: use lcm from kernel lib
  nfsd4: decrease nfsd4_encode_fattr stack usage
  nfsd: fix encode_entryplus_baggage stack usage
  nfsd4: simplify xdr encoding of nfsv4 names
  nfsd4: encode_rdattr_error cleanup
  nfsd4: nfsd4_encode_fattr cleanup
  minor svcauth_gss.c cleanup
  nfsd4: better VERIFY comment
  nfsd4: break only delegations when appropriate
  NFSD: Fix a memory leak in nfsd4_create_session
  sunrpc: get rid of use_gssp_lock
  sunrpc: fix potential race between setting use_gss_proxy and the upcall rpc_clnt
  sunrpc: don't wait for write before allowing reads from use-gss-proxy file
  nfsd: get rid of unused function definition
  Define op_iattr for nfsd4_open instead using macro
  NFSD: fix compile warning without CONFIG_NFSD_V3
  ...

net: replace macros net_random and net_srandom with direct calls to prandom

2014-01-14T23:15:25+00:00

This patch removes the net_random and net_srandom macros and replaces
them with direct calls to the prandom ones. As new commits only seem to
use prandom_u32 there is no use to keep them around.
This change makes it easier to grep for users of prandom_u32.

Signed-off-by: Aruna-Hewapathirane 
Suggested-by: Hannes Frederic Sowa 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

net/sunrpc/cache: simplify code by using hex_pack_byte()

2013-12-12T16:37:17+00:00

hex_pack_byte() is a fast way to convert a byte in its ASCII representation. We
may use it instead of custom approach.

Signed-off-by: Andy Shevchenko 
Signed-off-by: J. Bruce Fields

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2013-07-14T18:42:26+00:00

Pull more vfs stuff from Al Viro:
 "O_TMPFILE ABI changes, Oleg's fput() series, misc cleanups, including
  making simple_lookup() usable for filesystems with non-NULL s_d_op,
  which allows us to get rid of quite a bit of ugliness"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  sunrpc: now we can just set ->s_d_op
  cgroup: we can use simple_lookup() now
  efivarfs: we can use simple_lookup() now
  make simple_lookup() usable for filesystems that set ->s_d_op
  configfs: don't open-code d_alloc_name()
  __rpc_lookup_create_exclusive: pass string instead of qstr
  rpc_create_*_dir: don't bother with qstr
  llist: llist_add() can use llist_add_batch()
  llist: fix/simplify llist_add() and llist_add_batch()
  fput: turn "list_head delayed_fput_list" into llist_head
  fs/file_table.c:fput(): add comment
  Safer ABI for O_TMPFILE

rpc_create_*_dir: don't bother with qstr

2013-07-14T13:02:28+00:00

just pass the name

Signed-off-by: Al Viro

sunrpc: Don't schedule an upcall on a replaced cache entry.

2013-07-01T21:53:28+00:00

When a cache entry is replaced, the "expiry_time" get set to
zero by a call to "cache_fresh_locked(..., 0)" at the end of
"sunrpc_cache_update".

This low expiry time makes cache_check() think that the 'refresh_age'
is negative, so the 'age' is comparatively large and a refresh is
triggered.
However refreshing a replaced entry it pointless, it cannot achieve
anything useful.

So teach cache_check to ignore a low refresh_age when expiry_time
is zero.

Reported-by: Bodo Stroesser 
Signed-off-by: NeilBrown 
Signed-off-by: J. Bruce Fields

net/sunrpc: xpt_auth_cache should be ignored when expired.

2013-07-01T21:53:28+00:00

commit d202cce8963d9268ff355a386e20243e8332b308
    sunrpc: never return expired entries in sunrpc_cache_lookup

moved the 'entry is expired' test from cache_check to
sunrpc_cache_lookup, so that it happened early and some races could
safely be ignored.

However the ip_map (in svcauth_unix.c) has a separate single-item
cache which allows quick lookup without locking.  An entry in this
case would not be subject to the expiry test and so could be used
well after it has expired.

This is not normally a big problem because the first time it is used
after it is expired an up-call will be scheduled to refresh the entry
(if it hasn't been scheduled already) and the old entry will then
be invalidated.  So on the second attempt to use it after it has
expired, ip_map_cached_get will discard it.

However that is subtle and not ideal, so replace the "!cache_valid"
test with "cache_is_expired".
In doing this we drop the test on the "CACHE_VALID" bit.  This is
unnecessary as the bit is never cleared, and an entry will only
be cached if the bit is set.

Reported-by: Bodo Stroesser 
Signed-off-by: NeilBrown 
Signed-off-by: J. Bruce Fields