linux.git/lib, branch v4.4.177

assoc_array: Fix shortcut creation

2019-03-23T07:44:33+00:00

[ Upstream commit bb2ba2d75a2d673e76ddaf13a9bd30d6a8b1bb08 ]

Fix the creation of shortcuts for which the length of the index key value
is an exact multiple of the machine word size.  The problem is that the
code that blanks off the unused bits of the shortcut value malfunctions if
the number of bits in the last word equals machine word size.  This is due
to the "<<" operator being given a shift of zero in this case, and so the
mask that should be all zeros is all ones instead.  This causes the
subsequent masking operation to clear everything rather than clearing
nothing.

Ordinarily, the presence of the hash at the beginning of the tree index key
makes the issue very hard to test for, but in this case, it was encountered
due to a development mistake that caused the hash output to be either 0
(keyring) or 1 (non-keyring) only.  This made it susceptible to the
keyctl/unlink/valid test in the keyutils package.

The fix is simply to skip the blanking if the shift would be 0.  For
example, an index key that is 64 bits long would produce a 0 shift and thus
a 'blank' of all 1s.  This would then be inverted and AND'd onto the
index_key, incorrectly clearing the entire last word.

Fixes: 3cb989501c26 ("Add a generic associative array implementation.")
Signed-off-by: David Howells 
Signed-off-by: James Morris 
Signed-off-by: Sasha Levin

test_hexdump: use memcpy instead of strncpy

2019-02-20T09:13:14+00:00

commit b1286ed7158e9b62787508066283ab0b8850b518 upstream.

New versions of gcc reasonably warn about the odd pattern of

	strncpy(p, q, strlen(q));

which really doesn't make sense: the strncpy() ends up being just a slow
and odd way to write memcpy() in this case.

Apparently there was a patch for this floating around earlier, but it
got lost.

Acked-again-by: Andy Shevchenko 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

seq_buf: Make seq_buf_puts() null-terminate the buffer

2019-02-20T09:13:12+00:00

[ Upstream commit 0464ed24380905d640030d368cd84a4e4d1e15e2 ]

Currently seq_buf_puts() will happily create a non null-terminated
string for you in the buffer. This is particularly dangerous if the
buffer is on the stack.

For example:

  char buf[8];
  char secret = "secret";
  struct seq_buf s;

  seq_buf_init(&s, buf, sizeof(buf));
  seq_buf_puts(&s, "foo");
  printk("Message is %s\n", buf);

Can result in:

  Message is fooªªªªªsecret

We could require all users to memset() their buffer to zero before
use. But that seems likely to be forgotten and lead to bugs.

Instead we can change seq_buf_puts() to always leave the buffer in a
null-terminated state.

The only downside is that this makes the buffer 1 character smaller
for seq_buf_puts(), but that seems like a good trade off.

Link: http://lkml.kernel.org/r/20181019042109.8064-1-mpe@ellerman.id.au

Acked-by: Kees Cook 
Signed-off-by: Michael Ellerman 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Sasha Levin

rhashtable: add schedule points

2019-02-08T10:25:31+00:00

commit ae6da1f503abb5a5081f9f6c4a6881de97830f3e upstream.

Rehashing and destroying large hash table takes a lot of time,
and happens in process context. It is safe to add cond_resched()
in rhashtable_rehash_table() and rhashtable_free_and_destroy()

Signed-off-by: Eric Dumazet 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

rhashtable: add rhashtable_lookup_get_insert_key()

2019-02-08T10:25:30+00:00

commit 5ca8cc5bf11faed257c762018aea9106d529232f upstream.

This patch modifies __rhashtable_insert_fast() so it returns the
existing object that clashes with the one that you want to insert.
In case the object is successfully inserted, NULL is returned.
Otherwise, you get an error via ERR_PTR().

This patch adapts the existing callers of __rhashtable_insert_fast()
so they handle this new logic, and it adds a new
rhashtable_lookup_get_insert_key() interface to fetch this existing
object.

nf_tables needs this change to improve handling of EEXIST cases via
honoring the NLM_F_EXCL flag and by checking if the data part of the
mapping matches what we have.

Cc: Herbert Xu 
Cc: Thomas Graf 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Herbert Xu 
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

lib/interval_tree_test.c: allow users to limit scope of endpoint

2018-12-21T13:09:49+00:00

[ Upstream commit a8ec14d4f6aa8e245efacc992c8ee6ea0464ce2a ]

Add a 'max_endpoint' parameter such that users may easily limit the size
of the intervals that are randomly generated.

Link: http://lkml.kernel.org/r/20170518174936.20265-4-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

lib/rbtree-test: lower default params

2018-12-21T13:09:49+00:00

[ Upstream commit 0b548e33e6cb2bff240fdaf1783783be15c29080 ]

Fengguang reported soft lockups while running the rbtree and interval
tree test modules.  The logic for these tests all occur in init phase,
and we currently are pounding with the default values for number of
nodes and number of iterations of each test.  Reduce the latter by two
orders of magnitude.  This does not influence the value of the tests in
that one thousand times by default is enough to get the picture.

Link: http://lkml.kernel.org/r/20171109161715.xai2dtwqw2frhkcm@linux-n805
Signed-off-by: Davidlohr Bueso 
Reported-by: Fengguang Wu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

lib/rbtree_test.c: make input module parameters

2018-12-21T13:09:49+00:00

[ Upstream commit 223f8911eace60c787f8767c25148b80ece9732a ]

Allows for more flexible debugging.

Link: http://lkml.kernel.org/r/20170719014603.19029-5-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

lib/interval_tree_test.c: allow full tree search

2018-12-21T13:09:49+00:00

[ Upstream commit c46ecce431ebe6b1a9551d1f530eb432dae5c39b ]

...  such that a user can specify visiting all the nodes in the tree
(intersects with the world).  This is a nice opposite from the very
basic default query which is a single point.

Link: http://lkml.kernel.org/r/20170518174936.20265-5-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

lib/interval_tree_test.c: make test options module parameters

2018-12-21T13:09:49+00:00

[ Upstream commit a54dae0338b7f01eb0f9c7571fb9b74f791d1c6b ]

Allows for more flexible debugging.

Link: http://lkml.kernel.org/r/20170518174936.20265-3-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin