This is a simple mechanical transformation done by:

@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
  (E)

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Reviewed-by: SeongJae Park <sj@kernel.org> # for damon
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() >> 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p & (LITERAL))

// Add one to the literal.
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value & (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p & (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Call to build_initial_monmap() is one stone two birds.  Explicitly it
initializes err variable. Implicitly it initializes ->monmap via call to
kzalloc().  We should only declare err and ->monmap is taken care of by
ceph_monc_init() prototype.

Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Fix some spelling mistakes in comments:
enconding  ==> encoding
ambigous  ==> ambiguous
orignal  ==> original
encyption  ==> encryption

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since a few years, kernel addresses are no longer included in oops
dumps, at least on x86.  All we get is a symbol name with offset and
size.

This is a problem for ceph_connection_operations handlers, especially
con->ops->dispatch().  All three handlers have the same name and there
is little context to disambiguate between e.g. monitor and OSD clients
because almost everything is inlined.  gdb sneakily stops at the first
matching symbol, so one has to resort to nm and addr2line.

Some of these are already prefixed with mon_, osd_ or mds_.  Let's do
the same for all others.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Jeff Layton <jlayton@kernel.org>

Implement msgr2.1 wire protocol, available since nautilus 14.2.11
and octopus 15.2.5.  msgr2.0 wire protocol is not implemented -- it
has several security, integrity and robustness issues and therefore
considered deprecated.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

msgr2 supports two connection modes: crc (plain) and secure (on-wire
encryption).  Connection mode is picked by server based on input from
client.

Introduce ms_mode option:

  ms_mode=legacy        - msgr1 (default)
  ms_mode=crc           - crc mode, if denied fail
  ms_mode=secure        - secure mode, if denied fail
  ms_mode=prefer-crc    - crc mode, if denied agree to secure mode
  ms_mode=prefer-secure - secure mode, if denied agree to crc mode

ms_mode affects all connections, we don't separate connections to mons
like it's done in userspace with ms_client_mode vs ms_mon_client_mode.

For now the default is legacy, to be flipped to prefer-crc after some
time.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

For libceph, this ensures that libceph instance sharing (share option)
continues to work.  For rbd, this avoids blocklisting alive lock owners
(locker addr is always LEGACY, while watcher addr is ANY in nautilus).

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

In preparation for msgr2, make the cluster send us maps with addrvecs
including both LEGACY and MSGR2 addrs instead of a single LEGACY addr.
This means advertising support for SERVER_NAUTILUS and also some older
features: SERVER_MIMIC, MONENC and MONNAMES.

MONNAMES and MONENC are actually pre-argonaut, we just never updated
ceph_monmap_decode() for them.  Decoding is unconditional, see commit
23c625ce3065 ("libceph: assume argonaut on the server side").

SERVER_MIMIC doesn't bear any meaning for the kernel client.

Since ceph_decode_entity_addrvec() is guarded by encoding version
checks (and in msgr2 case it is guarded implicitly by the fact that
server is speaking msgr2), we assume MSG_ADDR2 for it.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

In preparation for msgr2, factor out finish_auth() so it is suitable
for both existing MAuth message based authentication and upcoming msgr2
authentication exchange.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>