ubusd maintains a per-client tx_queue containing references to message
buffers that have not been sent yet (due to the socket blocking). This
is a fixed-size, 64-element queue.
When more than 64 elements are queued, subsequent elements are simply
dropped. Thus, a client that is waiting for those messages will block
indefinitely. In particular, this happens when more than +- 250 objects
are registered on the bus and either "ubus list" or "ubus wait_for" is
called. The responses to these requests consist of a message buffer per
object. Since in practice, ubusd will not yield between the sends of
these message buffers, the client has no time to process them and
eventually the output socket blocks. After 64 more objects, the rest is
dropped, including the final message that indicates termination. Thus,
the client waits indefinitely for the termination message.
To solve this, turn the tx_queue into a variable-sized linked list
instead of a fixed-size queue.
To maintain the linked list, an additional structure ubus_msg_buf_list
is created. It is not possible to add the linked list to ubus_msg_buf,
because that is shared between clients.
Note that this infinite tx_queue opens the door to a DoS attack. You can
open a client and a server connection, then send messages from the
client to the server without ever reading anything on the server side.
This will eventually lead to an out-of-memory. However, such a DoS
already existed anyway, it just requires opening multiple server
connections and filling up the fixed-size queue on each one. To protect
against such DoS attacks, we'd need to:
- keep a global maximum queue size that applies to all rx and tx queues
together;
- stop reading from any connection when the maximum is reached;
- close any connection when it hasn't become writeable after some
timeout.
Fixes: https://bugs.openwrt.org/index.php?do=details&task_id=1525
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Add a new `ABIVERSION` define which allows to control the SOVERSION used
for the built shared library. This is needed for downstream packaging to
properly track breaking ABI changes when updating to newer versions of
the library.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
When ubus is running as root, /var/run/ubus most likely hasn't been
created as well (as that's the homedir of user ubus, and if a user
ubus was found, then ubus would run being that user).
Blindly attempt to create the directory (which won't do any harm if
it does exist and/or ubus is not running as root) to still be able to
start ubus in case of user ubus not existing.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Add support for wildcard in methods to permit access to all methods
defined by the object. This can be usefull for process that run as
non-root user and needs to access ubus method.
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Support for "subscribe" command was added years ago in the commit
453b87f631 ("cli: add support for subscribing to objects"). Document
its usage.
Cc: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
If the Lua number exceeds the maximum value representable by an
unsigned 32bit integer, store it in an unsigned 64bit integer
field instead.
Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
[align code style, reword commit message]
Signed-off-by: Jo-Philipp Wich <jo@mein.io>
In commit 5d7ca8309d ("ubusd/libubus-io: fix variable sized struct
position warning") the position of cmsghdr struct has been changed in
order to fix clang-9 compiler warning, but it has introduced regression
in at least `logread` which hanged indefinitely.
So this patch reworks the socket descriptor passing in a way recommended
in the `cmsg(3)` manual page.
Ref: http://lists.infradead.org/pipermail/openwrt-devel/2019-December/020840.html
Fixes: 5d7ca8309d ("ubusd/libubus-io: fix variable sized struct position warning")
Reported-by: Hannu Nyman <hannu.nyman@welho.com>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
In commit 08f17c87a0 ("add fuzzer and cram based unit tests") some
fuzz/unit tests were added so enable them on CI as well.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
blob_parse expects blobs from trusted inputs, but it can be supplied
with possibly malicious blobs from untrusted inputs as well, which might
lead to undefined behaviour and/or crash of ubus daemon. In order to
prevent such conditions, switch to blob_parse_untrusted which should
hopefully handle such untrusted inputs appropriately.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
scan-build from clang-9 has reported following:
libubox/list.h:141:2: warning: Use of memory after it is freed
_list_add(_new, head, head->next);
Signed-off-by: Petr Štetiar <ynezz@true.cz>
This dereference could possibly happen if the calloc call fails as the
return value is unchecked. While at it refactor the code little bit to
make it easier to follow, use safe list iterator and provide return
value for ubusd_monitor_connect.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
scan-build from clang-9 has reported following:
libubox/list.h:83:22: warning: Use of memory after it is freed
entry->next->prev = entry->prev;
^~~~~~~~~~~
ubusd_event.c:42:3: warning: Use of memory after it is freed
ubusd_delete_event_source(ev);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Which might be a false positives, but in order to make the code pass the
static analyzer checks, rewrite the while loops on lists with the safe
list iterator.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
scan-build from clang-9 has reported following:
ubus.c:837:16: warning: Access to field 'rnotify' results in a dereference of a null pointer (loaded from variable 'sub')
sub->rnotify = luaL_ref(L, -2);
Which is false positive as the lua_error() does a long jump and
therefore never returns and this long jump probably confuses the static
analyzer. So this patch workarounds this false positive by helping
static analyzer by using common Lua idiom which is to return
lua_error()'s return value.
Ref: https://www.lua.org/manual/5.1/manual.html#lua_error
Addresses-Coverity-ID: 1412355 ("Dereference after null check")
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Fixes following error reported by clang-9 analyzer:
examples/server.c:244:2: warning: Value stored to 'argc' is never read
argc -= optind;
^ ~~~~~~
examples/server.c:245:2: warning: Value stored to 'argv' is never read
argv += optind;
^ ~~~~~~
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Uses currently proof-of-concept openwrt-ci[1] in order to:
* improve the quality of the codebase in various areas
* decrease code review time and help merging contributions faster
* get automagic feedback loop on various platforms and tools
- out of tree build with OpenWrt SDK on following targets:
* ath79-generic
* imx6-generic
* malta-be
* mvebu-cortexa53
- out of tree native build on x86/64 with GCC (versions 7, 8, 9) and Clang 10
- out of tree native x86/64 static code analysis with cppcheck and
scan-build from Clang 9
1. https://gitlab.com/ynezz/openwrt-ci/
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Fixes following error reported by clang-9 analyzer:
libubus.c:286:19: error: incompatible pointer types assigning to 'struct blob_attr *' from 'char *' [-Werror,-Wincompatible-pointer-types]
ctx->msgbuf.data = (char *) calloc(UBUS_MSG_CHUNK_SIZE, sizeof(char));
Result of 'calloc' is converted to a pointer of type 'struct blob_attr',
which is incompatible with sizeof operand type 'char'.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
clang-9 on x86/64 has reported following warnings/errors:
libubus-acl.c:123:2: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
libubus-io.c:108:18: error: comparison of integers of different signs: 'int' and 'size_t' (aka 'unsigned long') [-Werror,-Wsign-compare]
libubus-io.c:395:56: error: comparison of integers of different signs: 'ssize_t' (aka 'long') and 'size_t' (aka 'unsigned long') [-Werror,-Wsign-compare]
libubus-req.c:441:4: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
ubusd_acl.c:119:18: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
ubusd_acl.c:152:5: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
ubusd_acl.c:348:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
ubusd_acl.c:352:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
ubusd_acl.c:357:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
ubusd_acl.c:362:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
ubusd_acl.c:367:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
ubusd_acl.c:447:16: error: comparison of integers of different signs: 'int' and '__size_t' (aka 'unsigned long') [-Werror,-Wsign-compare]
ubusd_acl.c:502:18: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
ubusd.c:123:13: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
ubusd.c:170:15: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
ubusd.c:262:43: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
ubusd.c:287:30: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
ubusd_event.c:170:18: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
ubusd_obj.c:71:2: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Fixes following clang-9 compiler warnings:
ubusd.c:99:18: error: field 'h' with variable sized type 'struct cmsghdr' not at the end of a struct or class is a GNU extension [-Werror,-Wgnu-variable-sized-type-not-at-end]
struct cmsghdr h;
^
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Fixes following clang-9 compiler warning:
ubusd.c:36:19: error: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Werror,-Wsign-compare]
if (ub->refcount == ~0) {
~~~~~~~~~~~~ ^ ~~
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Let's enforce additional automatic checks enforced by the compiler in
order to catch possible errors during compilation.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
If the header is read but not the remainder of the message, the stream
will be out of sync and parsing of future messages won't work
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Adds event send access list support in ubus via the "send" keyword
Example of a json file:
{
"user": "superuser",
"send": [ "wireless.*" ],
}
Signed-off-by: Koen Dergent <koen.cj.dergent@gmail.com>
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
Adds event listen access list support in ubus via the "listen" keyword
Example of a json file:
{
"user": "superuser",
"listen": [ "network.*" ],
}
Signed-off-by: Koen Dergent <koen.cj.dergent@gmail.com>
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
Wildcard access list support was failing in case multiple wildcards
entries were defined and/or when a specific access list string
overlapped a wildcard entry.
Root cause of the problem was the way how wildcard entries were sorted
in the avl tree by the compare function ubusd_acl_match_path resulting
into a non acces list match for a given object path.
The avl_tree sorting has been changed to make use of avl_strcmp; as such
there's no distinction anymore between non-wildcard and wildcard entries
in the avl_tree compare function as the boolean partial marks an access
list entry as a wildcard entry.
When trying to find an access list match for an object path the access list
tree is iterated as long as the number of characters between the access list
string and object path is monotonically increasing.
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
UBUS_MSG_INVOKE and UBUS_MSG_DATA can be sent without UBUS_ATTR_DATA
present. Most ubus users assume that the msg argument passed can never
be NULL, so this change prevents a crash
Signed-off-by: Felix Fietkau <nbd@nbd.name>
The callback function registered to be invoked when subscribing to a
notification was only passed the notification data (if any) but not the name
of the notification.
This name is now passed as second argument to remain backwards compatible.
The example subscriber.lua has also be updated.
Signed-off-by: Dirk Feytons <dirk.feytons@gmail.com>
==18834== Warning: invalid file descriptor -1 in syscall close()
==18834== at 0x5326D20: __close_nocancel (syscall-template.S:84)
==18834== by 0x5046DC7: ubus_process_obj_msg (libubus-obj.c:143)
==18834== by 0x5045E98: ubus_process_msg (libubus.c:106)
==18834== by 0x50468D0: ubus_handle_data (libubus-io.c:314)
==18834== by 0x4E3D125: uloop_run_events (uloop.c:198)
==18834== by 0x4E3D125: uloop_run_timeout (uloop.c:555)
==18834== by 0x109BEF: uloop_run (uloop.h:111)
==18834== by 0x109BEF: main (main.c:25)
Signed-off-by: John Crispin <john@phrozen.org>
valgrind complained about this one
==18632== Warning: invalid file descriptor -1 in syscall close()
==18632== at 0x5326D20: __close_nocancel (syscall-template.S:84)
==18632== by 0x5046C02: ubus_process_invoke (libubus-obj.c:98)
==18632== by 0x5046DC3: ubus_process_obj_msg (libubus-obj.c:142)
==18632== by 0x5045E98: ubus_process_msg (libubus.c:106)
==18632== by 0x50468D0: ubus_handle_data (libubus-io.c:314)
==18632== by 0x4E3D125: uloop_run_events (uloop.c:198)
==18632== by 0x4E3D125: uloop_run_timeout (uloop.c:555)
==18632== by 0x109BEF: uloop_run (uloop.h:111)
==18632== by 0x109BEF: main (main.c:25)
Signed-off-by: John Crispin <john@phrozen.org>
Even with the tx_queue-ing issue resolved, what
seems to happen afterwards, is that all the messages
seems to get through, but the client still loops
in the `ubus_complete_request()` waiting for
`req->status_msg` or for a timeout.
Though, the timeout does not seem to happen, because
the data is processed in `ubus_poll_data()`, with
a infinite poll() timeout (ubus_complete_request() is
called with timeout 0).
It's likely that either the `seq` or `peer` sent from
ubusd are wrong, and the client cannot get the correct
ubus request in `ubus_process_req_msg()`.
I haven't digged too deep into this ; setting the
`retmsg` object on the client struct seems to have
resolved any hanging with the `ubus list` command.
Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name> [fix placement of retmsg in cl]
Should save a few cycles, since the data that's
being changed is only the seq number.
And the `ub` is always created as shared.
Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>
This makes it clear that `ubus_msg_send()` is only
about sending and queue-ing messages, and has nothing
to do with free-ing.
It can be a bit misleading/confusing when trying to go
through the code and make assumptions about whether a
buffer is free'd in ubus_send_msg(), or is free'd outside.
In `ubusd_proto_receive_message()` the `ubus_msg_free()`
is now called before the `if (ret == -1)` check.
That way, all callbacks will have their messages free'd,
which is what's desired, but confusing, because:
* ubusd_handle_invoke() called ubus_msg_free() before returning -1
* ubusd_handle_notify() called ubus_msg_free() before returning -1
* ubusd_handle_response() called ubus_msg_send(,,free=true) before returning -1
* ubus_msg_send() would call ubus_msg_send(,,free=false)
* all other callback callers would `ubus_msg_send(,,free=true)`
(free the buffers in ubus_msg_send() )
In all other places, where `ubus_msg_send(,,free=true)`
an explicit `ubus_msg_free()` was added.
Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Objects are stored in the ubus context in an AVL tree. An AVL tree
node contains a pointer to a key value. For the ubus context, this
points to the id member of the object structure. In
ubus_remove_object_cb, the id member is set to zero and then after,
avl_delete is called and fails. To fix this, we call avl_delete
before setting the object id to zero.
Signed-off-by: Bob Ham <bob.ham@tomltd.co.uk>
Variable listen_timeout is redefined as a function resulting into
a compile issue. Define the function as ubus_cli_listen_timeout
to fix the compile issue.
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
When ubus connect fails ctx->sock.eof will be set but ctx->sock.error
can be set as well. Reset ctx->sock.error as well when doing ubus
reconnect
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
