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Placing it in its own section will ease its finding, particularly in
gdb which is too dumb to find anything in memory. Now it will be
sufficient to issue this:
$ gdb -ex "info files" -ex "quit" ./haproxy core 2>/dev/null |grep _post_mortem
0x0000000000cfd300 - 0x0000000000cfe780 is _post_mortem
or this:
$ objdump -h haproxy|grep post
34 _post_mortem 00001480 0000000000cfd300 0000000000cfd300 008fc300 2**8
to spot the symbol's address. Then it can be read this way:
(gdb) p *(struct post_mortem *)0x0000000000cfd300
(cherry picked from commit 93c3f2a0b4da77c0317496b8585192fb64ef400f)
Signed-off-by: Willy Tarreau <w@1wt.eu>
In order to ease finding of the post_mortem struct in core dumps, let's
make it start with a recognizable pattern of exactly 32 chars (to
preserve alignment):
"POST-MORTEM STARTS HERE+7654321\0"
It can then be found like this from gdb:
(gdb) find 0x000000012345678, 0x0000000100000000, 'P','O','S','T','-','M','O','R','T','E','M'
0xcfd300 <post_mortem>
1 pattern found.
Or easier with any other more practical tool (who as ever used "find" in
gdb, given that it cannot iterate over maps and is 100% useless?).
(cherry picked from commit 989b02e1930d7ecd1a728c3d18ccfba095cdd636)
Signed-off-by: Willy Tarreau <w@1wt.eu>
We want it to be accessible from debuggers for inspection and it's
currently unavailable. Let's start by exporting it as a first step.
(cherry picked from commit fba48e1c40287f1abb4066935f2436bd0b8cd7a4)
Signed-off-by: Willy Tarreau <w@1wt.eu>
Commit 091de0f9b2 ("MINOR: debug: slightly change the thread_dump_pointer
signification") caused the following warning to be emitted when threads
are disabled:
src/debug.c: In function 'ha_thread_dump_one':
src/debug.c:359:9: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
Let's just disguise the pointer to silence it. It should be backported
where the patch above was backported, since it was part of a series aiming
at making thread dumps more exploitable from core dumps.
(cherry picked from commit f163cbfb7f893a06d158880a753cad01908143d8)
[wt: s/MT_LIST_FOR_EACH_ENTRY_LOCKED/mt_list_for_each_entry_safe/ with
two backup elements in 3.0]
Signed-off-by: Willy Tarreau <w@1wt.eu>
Each server is inserted in a global list named servers_list on
new_server(). This list is then only used to finalize servers
initialization after parsing.
On dynamic server creation, there is no issue as new_server() is under
thread isolation. However, when a server is deleted after its refcount
reached zero, srv_drop() removes it from servers_list without lock
protection. In the longterm, this can cause list corruption and crashes,
especially if multiple adjacent servers are removed in parallel.
To fix this, convert servers_list to a mt_list. This should not impact
performance as servers_list is not used during runtime outside of server
creation/deletion.
This should fix github issue #2733. Thanks to Chris Staite who first
found the issue here.
This must be backported up to 2.6.
(cherry picked from commit 7a02fcaf20dbc19db36052bbc7001bcea3912ab5)
Signed-off-by: Willy Tarreau <w@1wt.eu>
There is no reason to disable the 0-copy data forwarding if an end-of-stream
was reported on the consumer side. Indeed, the consumer will send data in
this case. So there is no reason to check the read side here.
This patch may be backported as far as 2.9.
(cherry picked from commit 362de90f3e4ddd0c15331c6b9cb48b671a6e2385)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
When the response forwarding is aborted, we must not report a client abort
if a EOS was seen on client side. On abort performed by the stream must be
considered.
This bug was introduced when the SHUTR was splitted in 2 flags.
This patch must be backported as far as 2.8.
(cherry picked from commit 5970c6abec3e0ee4ac44364e999cae2cc852f4c8)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
When some data must be sent to the endpoint but an error was previously
reported, nothing is performed and we leave. But, in this case, the SC is not
notified the sends are blocked.
It is indeed an issue if the endpoint reports an error after consuming all
data from the SC. In the endpoint the outgoing data are trashed because of
the error, but on the SC, everything was sent, even if an error was also
reported.
Because of this bug, it is possible to have outgoing data blocked at the SC
level but without any write timeout armed. In some cases, this may lead to
blocking conditions where the stream is never closed.
So now, when outgoing data cannot be sent because an previous error was
triggered, a blocked send is reported. This way, it is possible to report a
write timeout.
This patch should fix the issue #2754. It must be backported as far as 2.8.
(cherry picked from commit fbc3de6e9e59679d2e9ece3984ce31b6a7dd418f)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
If a dynamic server is added with check or agent-check, its refcount is
incremented after server keyword parsing. However, if add server fails
at a later stage, refcount is only decremented once, which prevented the
server to be fully released.
This causes a leak with a server which is detached from most of the
lists but still exits in the system.
This bug is considered minor as only a few conditions may cause a
failure in add server after check/agent-check initialization. This is
the case if there is a naming collision or the dynamic ID cannot be
generated.
To fix this, simply decrement server refcount on add server error path
if either check and/or agent-check are flagged as activated.
This bug is related to github issue #2733. Thanks to Chris Staite who
first found the leak.
This must be backported up to 2.6.
(cherry picked from commit 116178563c2fb57e28a76838cf85c4858b185b76)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
On systems where many libs are loaded, it's hard to track suspected
leaks. Having a per-DSO summary makes it more convenient. That's what
we're doing here by summarizing all calls per DSO before showing the
total.
(cherry picked from commit 401fb0e87a2cea7171e4d37da6094755eb10a972)
Signed-off-by: Willy Tarreau <w@1wt.eu>
It was found in a large "show profiling memory" output that a few entries
have a NULL return address, which causes confusion because this address
will be reused by the next new allocation caller, possibly resulting in
inconsistencies such as "free() ... pool=trash" which makes no sense. The
cause is in fact that the first caller had an entry->info pointing to the
trash pool from a p_alloc/p_free with a NULL return address, and the second
had a different type and reused that entry.
Let's make sure undecodable stacks causing an apparent NULL return address
all lead to the "other" bin.
While this is not exactly a bug, it would make sense to backport it to the
recent branches where the feature is used (probably at least as far as 2.8).
(cherry picked from commit 5091f90479ab4d963b55cb725cee8201d93521d9)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
As described in GH #2765, there were situations where http connections
would be re-used for requests to different endpoints, which is obviously
unexpected. In GH #2765, this occured with httpclient and UNIX socket
combination, but later code analysis revealed that while disabling http
reuse on httpclient proxy helped, it didn't fix the underlying issue since
it was found that conn_calculate_hash_sockaddr() didn't take into account
families such as AF_UNIX or AF_CUST_SOCKPAIR, and because of that the
sock_addr part of the connection wasn't hashed.
To properly fix the issue, let's explicly handle UNIX (both regular and
ABNS) and AF_CUST_SOCKPAIR families, so that the destination address is
properly hashed. To prevent this bug from re-appearing: when the family
isn't known, instead of doing nothing like before, let's fall back to a
generic (unoptimal) hashing which hashes the whole sockaddr_storage struct
As a workaround, http-reuse may be disabled on impacted proxies.
(unfortunately this doesn't help for httpclient since reuse policy
defaults to safe and cannot be modified from the config)
It should be backported to all stable versions.
Shout out to @christopherhibbert for having reported the issue and
provided a trivial reproducer.
[ada: prior to 3.0, ctx adjt is required because conn_hash_update()'s
prototype is slightly different]
(cherry picked from commit b5b40a9843e505ed84153327ab897ca0e8d9a571)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
When data are sent via the zero-copy data forwarding, in h2_done_ff, we must
be sure to remove the H2 stream from the send list if something is send. It
was only performed if no blocking condition was encountered. But we must
also do it if something is sent. Otherwise the transfer may be blocked till
timeout.
This patch must be backported as far as 2.9.
(cherry picked from commit ded28f6e5c210b49ede7edb25cd4b39163759366)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
During the zero-copy data forwarding, the caller specify the maximum amount
of data the producer may push. However, the HTML stats applet does not use
it and can fill all the free space in the buffer. It is especially an issue
when the consumer is limited by a flow control, like the H2. Because we may
emit too large DATA frame in this case. It is especially visible with big
buffer (for instance 32k).
In the early age or zero-copy data forwarding, the caller was responsible to
pass a properly resized buffer. And during the different refactoring steps,
this has changed but the HTML stats applet was not updated accordingly.
To fix the bug, the buffer used to dump the HTML page is resized to be sure
not too much data are dumped.
This patch should solve the issue #2757. It must be backported to 3.0.
(cherry picked from commit 529e4f36a353bca292196e1344a79b8cd4ba143c)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
A stream may be shut without any HTX EOM reported to report a proper
closure. This is the case for QCS instances flagged with
QC_SF_UNKNOWN_PL_LENGTH. Shut is performed with an empty FIN emission
instead of a RESET_STREAM. This has been implemented since the following
patch :
24962dd178
BUG/MEDIUM: mux-quic: do not emit RESET_STREAM for unknown length
However, in case of HTTP/3, an empty FIN should only be done after a
full message is emitted, which requires at least a HEADERS frame. If an
empty FIN is emitted without it, client may interpret this as invalid
and close the connection. To prevent this, fallback to a RESET_STREAM
emission if no data were emitted on the stream.
This was reproduced using ngtcp2-client with 10% loss (-r 0.1) on a
remote host, with httpterm request "/?s=100k&C=1&b=0&P=400". An error
ERR_H3_FRAME_UNEXPECTED is returned by ngtcp2-client when the bug
occurs.
Note that this change is incomplete. The message validity depends solely
on the application protocol in use. As such, a new app_ops callback
should be implemented to ensure the stream is closed accordingly.
However, this first patch ensures that at least HTTP/3 case is valid
while keeping a minimal backport process.
This should be backported up to 2.8.
(cherry picked from commit 68c8c910238f0b759d75b4da2128370abf184cd1)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
Before this patch, when wrong argument was provided in the configuration for
mworker-max-reloads keyword, parser shows these errors below on the stderr:
[WARNING] (1820317) : config : parsing [haproxy.cfg:154] : (null)parsing [haproxy.cfg:154] : 'mworker-max-reloads' expects an integer argument.
In a case, when by mistake two arguments were provided instead of one, this has
also triggered a buggy error message:
[ALERT] (1820668) : config : parsing [haproxy.cfg:154] : 'mworker-max-reloads' cannot handle unexpected argument '45'.
[WARNING] (1820668) : config : parsing [haproxy.cfg:154] : (null)
So, as 'mworker-max-reloads' is parsed in discovery mode by master process
let's align now its parser with all others, which could be called for this
mode. Like this in cases, when there are too many args or argument isn't a
valid integer we return proper error codes to global section parser and
messages are formated properly.
This fix should be backported in all stable versions.
(cherry picked from commit af1d170122369094a1f3869791fb34fb7286e31e)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
replace specicy with specify in rfc7239 forwarded option description.
Multiple occurences were found.
May be backported in 2.8.
(cherry picked from commit 45cbbdc84551e51cdaf0046e1371e8495d053fb5)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
This issue came with this commit:
f627b92 BUG/MEDIUM: quic: always validate sender address on 0-RTT
and could be easily reproduced with picoquic QUIC client with -Q option
which splits a big ClientHello TLS message into two Initial datagrams.
A second condition must be fulfilled to reprodue this issue: picoquic
must not send the token provided by haproxy (NEW_TOKEN). To do that,
haproxy must be patched to prevent it to send such tokens.
Under these conditions, if haproxy has enough time to reply to the first Initial
datagrams, when it receives the second Initial datagram it sends a Retry paquet.
Then the client ignores the Retry paquet as mentionned by RFC 9000:
17.2.5.2. Handling a Retry Packet
A client MUST accept and process at most one Retry packet for each connection
attempt. After the client has received and processed an Initial or Retry packet
from the server, it MUST discard any subsequent Retry packets that it receives.
On its side, haproxy has closed the connection. When it receives the second
Initial datagram, it open a new connection but with Initial packets it
cannot decrypt (wrong ODCID) leaving the client without response.
To fix this, as the aim of the token (NEW_TOKEN) sent by haproxy is to validate
the peer address, in place of closing the connection when no token was received
for a 0RTT connection, one leaves this validation to the handshake process.
Indeed, the peer adress is validated during the handshake when a valid handshake
packet is received by the listener. But as one does not want haproxy to process
0RTT data when no token was received, one does not accept the connection before
the successful handshake completion. In addition to this, the 0RTT packets
are not released after successful handshake completion when no token was received
to leave a chance to haproxy to process these 0RTT data in such case (see
quic_conn_io_cb()).
Must be backported as far as 2.9.
(cherry picked from commit b1af5dabf0c4af1eda3a520a90332df1f4c12dcf)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
This bug came with this commit:
f627b92 BUG/MEDIUM: quic: always validate sender address on 0-RTT
If an error happens in quic_build_post_handshake_frames() during the
code exexuted for th NEW_TOKEN frame allocation, some could leak because
of the wrong label used to interrupt this function asap.
Replace the "goto leave" by "goto err" to deallocated such frames to fix
this issue.
Must be backported as far as 2.9.
(cherry picked from commit 19aa320f640f701544c3441787da1577a2479590)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
A "Connection: close" header is added to responses to avoid any connection
reuse. This should avoid errors on the client side.
(cherry picked from commit e7be13da87f8ec00470ef60bb43b85f0480fd85d)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
When a filter is registered on the data, it means it may change the payload
length by rewritting data. It means consumers of the message cannot trust the
expected length of payload as announced by the producer. The commit 8bd835b2d2
("MEDIUM: filters/htx: Don't rely on HTX extra field if payload is filtered")
was pushed to solve this issue. When the HTTP payload of a message is filtered,
the extra field is set to 0 to be sure it will never be used by error by any
consumer. However, it is not enough.
Indeed, the filters must be called before fowarding some data. They cannot be
by-passed. But if a consumer is unable to flush the HTX message, some outgoing
data can remain blocked in the channel's buffer. If some new data are then
pushed because there is some room in the channel's buffe, the producer will set
the HTX extra field. At this stage, if the consumer is unblocked and can send
again data, it is possible to call it to forward outgoing data blocked in the
channel's buffer before waking the stream up to filter new input data. It is the
purpose of the data fast-forwarding. In this case, the HTX extra field will be
seen by the consumer. It is unexpected and leads to undefined behavior.
One consequence of this bug is to perform a wrong chunking on compressed
messages, leading to processing errors at the end of the message, reported as
"ID--" in logs.
To fix the bug, a HTX flag is added to state the payload of the current HTX
message is altered. When this flag is set (HTX_FL_ALTERED_PAYLOAD), the HTX
extra field must not be trusted. And to keep things simple, when this flag is
set, the HTX extra field is automatically set to 0 when the HTX message is
loaded, in htxbuf() function.
It is probably the less intrusive way to fix the bug for now. But this part must
be reviewed to save meta-info of the HTX message outside of the message itself.
This commit should solve the issue #2741. It must be backported as far as 2.9.
(cherry picked from commit 52a3d807fc332b57b62f5e30aa6f697636a22695)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
In sc_notify() function, the consumer side of the SC is tested to verify if
we must perform a shutdown on the endpoint. To do so, no output data must be
present in the buffer and in the iobuf. However, there is a bug here, the
iobuf of the opposite SC is tested instead of the one of the current SC. So
a shutdown can be performed on the endpoint while there are still output
data in the iobuf that must be sent. Concretely, it can only be data blocked
in a pipe.
Because of this bug, data blocked in the pipe will be never sent. I've not
tested but I guess this may block the stream during the client or server
timeout.
This patch must be backported as far as 2.9.
(cherry picked from commit 0fcfed9e231f2bc3963fe6085598970db2174af1)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
If a parsing error is reported by the mux on the response payload, a proxy
error (PRXCOND) must be reported instead of a server abort (SRVCL). Because
of this bug, inavlid response may are reported as "SD--" or "SL--" in logs
instead of "PD--" or "PL--".
This patch must be backported to all stable versions.
(cherry picked from commit 6790067e79566b2ca5943e72200361c40001bde2)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
When a send attempt is performed on the opposite side from sc_notify() and
all outgoing data are sent while a shut was scheduled, the SE is shut down
because we consider all data were sent and no more are expected. However,
here we must also be carefull to have sent all pending data in the
iobuf. Indeed, some spliced data may be blocked. In this case, if the SE is
shut down, these data may be lost.
This patch should fix the original bug reported in #2749. It must be
backported as far as 2.9.
(cherry picked from commit 48f1e2b6fe8457bb5b9d8db9447157c244d871b7)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
Latest patches on the mworker rework skipped the httpclient_proxy
creation by accident. This is not supposed to happen because haproxy is
supposed to stop when the proxy creation failed, but it shows a flaw in
the API.
When the httpclient_proxy or the proxy used in parameter of
httpclient_new_from_proxy() is NULL, it will be dereferenced and cause a
crash.
The patch only returns a NULL when doing an httpclient_new() if the
proxy is not available.
Must be backported as far as 2.7.
(cherry picked from commit e7b7072943d658702eba3651d66c6093f1a79fa8)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
Since commit 53f52e67a0 ("BUG/MEDIUM: queue: always dequeue the backend when
redistributing the last server"), we've got two reports again still showing
the theoretically impossible condition in pendconn_add(), including a single
threaded one.
Thanks to the traces, the issue could be tracked down to the redispatch part.
In fact, in non-determinist LB algorithms (RR, LC, FAS), we don't perform the
LB if there are pending connections in the backend, since it indicates that
previous attempts already failed, so we directly return SRV_STATUS_FULL. And
contrary to a previous belief, it is possible to meet this condition with
be->served==0 when redispatching (and likely with maxconn not greater than
the number of threads).
The problem is that in this case, the entry is queued and then the
pendconn_must_try_again() function checks if any connections are currently
being served to detect if we missed a race, and tries again, but that
situation is not caused by a concurrent thread and will never fix itself,
resulting in the loop.
All that part around pendconn_must_try_again() is still quite brittle, and
a safer approach would involve a sequence counter to detect new arrivals
and dequeues during the pendconn_add() call. But it's more sensitive work,
probably for a later fix.
This fix must be backported wherever the fix above was backported. Thanks
to Patrick Hemmer, as well as Damien Claisse and Basha Mougamadou from
Criteo for their help on tracking this one!
(cherry picked from commit ca275d99ce02e72d707fc87da133d739cdda5146)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
If a small request is received on QUIC MUX frontend, it can be
transmitted directly with the FIN on attach operation. rcv_buf is
skipped by the stream layer. Thus, it is necessary to ensure that there
is similar behavior when FIN is reported either on attach or rcv_buf.
One difference was that se_expect_data() was called only for rcv_buf but
not on attach. This most obvious effect is that stream timeout was
deactivated for this request : client timeout was disabled on EOI but
server one not armed due to previous se_expect_no_data(). This prevents
the early closure of too long requests.
To fix this, add an invokation of se_expect_data() on attach operation.
This bug can simply be detected using httpterm with delay request (for
example /?t=10000) and using smaller client/server timeouts. The bug is
present if the request is not aborted on timeout but instead continue
until its proper HTTP 200 termination.
This has been introduced by the following commit :
85eabfbf67
MEDIUM: mux-quic: Don't expect data from server as long as request is unfinished
This must be backported up to 2.8.
(cherry picked from commit 232083c3e5ca3f23a44fa64def6a88dd257c3b23)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
To execute sample fetches and converters from lua. hlua API leverages the
sample API. Prior to executing the sample func, the arg checker is called
from hlua_run_sample_{fetch,conv}() to detect potential errors.
However, hlua_run_sample_{fetch,conv}() both pass NULL as <err> argument,
but it is wrong for two reasons. First we miss an opportunity to report
precise error messages to help the user know what went wrong during the
check.. and more importantly, some val check functions consider that the
<err> pointer is never NULL. This is the case for example with
check_crypto_hmac(). Because of this, when such val check functions
encounter an error, they will crash the process because they will try
to de-reference NULL.
This bug was discovered and reported by GH user @JB0925 on #2745.
Perhaps val check functions should make sure that the provided <err>
pointer is != NULL prior to de-referencing it. But since there are
multiple occurences found in the code and the API isn't clear about that,
it is easier to fix the hlua part (caller) for now.
To fix the issue, let's always provide a valid <err> pointer when
leveraging val_arg() check function pointer, and make use of it in case
or error to report relevant message to the user before freeing it.
It should be backported to all stable versions.
(cherry picked from commit f88f162868df9053ca71e3be0628221c36153d9a)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
hlua_ctx_renew() is called from unsafe places where the caller doesn't
expect it to LJMP.. however hlua_ctx_renew() makes use of Lua library
function that could potentially raise errors, such as lua_newthread(),
and it does nothing to catch errors. Because of this, haproxy could
unexpectedly crash. This was discovered and reported by GH user
@JB0925 on #2745.
To fix the issue, let's simply make hlua_ctx_renew() safe by applying
the same logic implemented for hlua_ctx_init() or hlua_ctx_destroy(),
which is catching Lua errors by leveraging SET_SAFE_LJMP_PARENT() helper.
It should be backported to all stable versions.
(cherry picked from commit d0e01051813bde5cb06bebe88102f2b2885b3dea)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
Pierre Bonnat reported that SRV-based server-template recently stopped
to work properly.
After reviewing the changes, it was found that the regression was caused
by a4d04c6 ("BUG/MINOR: server: make sure the HMAINT state is part of MAINT")
Indeed, HMAINT is not a regular maintenance flag. It was implemented in
b418c122 a4d04c6 ("BUG/MINOR: server: make sure the HMAINT state is part
of MAINT"). This flag is only set (and never removed) when the server FQDN
is changed from its initial config-time value. This can happen with "set
server fqdn" command as well as SRV records updates from the DNS. This
flag should ideally belong to server flags.. but it was stored under
srv_admin enum because cur_admin is properly exported/imported via server
state-file while regular server's flags are not.
Due to a4d04c6, when a server FQDN changes, the server is considered in
maintenance, and since the HMAINT flag is never removed, the server is
stuck in maintenance.
To fix the issue, we partially revert a4d04c6. But this latter commit is
right on one point: HMAINT flag was way too confusing and mixed-up between
regular MAINT flags, thus there's nothing to blame about a4d04c6 as it was
error-prone anyway.. To prevent such kind of bugs from happening again,
let's rename HMAINT to something more explicit (SRV_ADMF_FQDN_CHANGED) and
make it stand out under srv_admin enum so we're not tempted to mix it with
regular maintenance flags anymore.
Since a4d04c6 was set to be backported in all versions, this patch must
be backported there as well.
(cherry picked from commit 85298189bf4c268b15c33aea95e0cc35113e25f0)
Signed-off-by: Aurelien DARRAGON <adarragon@haproxy.com>
One main problem with panic dumps is that they're filling the dumping
thread's trash, and that the global thread_dump_buffer is too small to
catch enough of them.
Here we're proceeding differently. When dumping threads for a panic, we're
passing the magic value 0x2 as the buffer, and it will instruct the target
thread to allocate its own buffer using get_trash_chunk() (which is signal
safe), so that each thread dumps into its own buffer. Then the thread will
wait for the buffer to be consumed, and will assign its own thread_dump_buffer
to it. This way we can simply dump all threads' buffers from gdb like this:
(gdb) set $t=0
while ($t < global.nbthread)
printf "%s\n", ha_thread_ctx[$t].thread_dump_buffer.area
set $t=$t+1
end
For now we make it wait forever since it's only called on panic and we
want to make sure the thread doesn't leave and continues to use that trash
buffer or do other nasty stuff. That way the dumping thread will make all
of them die.
This would be useful to backport to the most recent branches to help
troubleshooting. It backports well to 2.9, except for some trivial
context in tinfo-t.h for an updated comment. 2.8 and older would also
require TAINTED_PANIC. The following previous patches are required:
MINOR: debug: make mark_tainted() return the previous value
MINOR: chunk: drop the global thread_dump_buffer
MINOR: debug: split ha_thread_dump() in two parts
MINOR: debug: slightly change the thread_dump_pointer signification
MINOR: debug: make ha_thread_dump_done() take the pointer to be used
MINOR: debug: replace ha_thread_dump() with its two components
(cherry picked from commit 278b9613a32ddb0b5ffa1d66e6c25f434758c65a)
[wt: ctx updt in tinfo-t for comment]
Signed-off-by: Willy Tarreau <w@1wt.eu>
At the few places we were calling ha_thread_dump(), now we're
calling separately ha_thread_dump_fill() and ha_thread_dump_done()
once the data are consumed.
(cherry picked from commit afeac4bc026e64e27d99e50480bff5bc1ee60cb9)
Signed-off-by: Willy Tarreau <w@1wt.eu>
This will allow the caller to decide whether to definitely clear the
pointer and release the thread, or to leave it unlocked so that it's
easy to analyse from the struct (the goal will be to use that in panic()
so that cores are easy to analyse).
(cherry picked from commit d7c34ba479f79ed42c709c64679b4e3d1310cddd)
Signed-off-by: Willy Tarreau <w@1wt.eu>
Now the thread_dump_pointer is returned ORed with 1 once done, or NULL
when cancelled (for now noone cancels). The goal will be to permit
the callee to provide its own pointer.
The ha_thread_dump_fill() function now returns the buffer pointer that
was used (without OR 1) or NULL, for ease of use from the caller.
(cherry picked from commit 091de0f9b2553463660a11c56598c4970d6b1066)
Signed-off-by: Willy Tarreau <w@1wt.eu>
We want to have a function to trigger the dump and another one to wait
for it to be completed. This will be important to permit panic dumps to
be done on local threads. For now this does not change anything, as the
function still calls the two new functions one after the other.
(cherry picked from commit 2036f5bba1637c8dad3eca577aa3bed4cc53caaf)
Signed-off-by: Willy Tarreau <w@1wt.eu>
This variable is not very useful and is confusing anyway. It was mostly
used to detect that a panic dump was still in progress, but we can now
check mark_tainted() for this. The pointer was set to one of the dumping
thread's trash chunks. Let's temporarily continue to copy the dumps to
that trash, we'll remove it later.
(cherry picked from commit a6698304e03847f3e114b22b4229b382f3ddffd1)
Signed-off-by: Willy Tarreau <w@1wt.eu>
Since mark_tainted() uses atomic ops to update the tainted status, let's
make it return the prior value, which will allow the caller to detect
if it's the first one to set it or not.
(cherry picked from commit 8e048603d1bba0721433a5ae0480fbf1ab6f4897)
Signed-off-by: Willy Tarreau <w@1wt.eu>
If a request is waiting for a protocol upgrade but it is not finished, the
data fast-forwarding is disabled. Otherwise, the request analyzers will miss
the end of the message.
This case is possible since the commit 01fb1a54 ("BUG/MEDIUM: mux-h1/mux-h2:
Reject upgrades with payload on H2 side only"). Indeed, before, a protocol
upgrade was not allowed for request with payload. But it is now possible and
this comes with a side-effect. It is not really satisfying but for now there
is no other way to sync the muxes and the applicative stream. It seems to be
a reasonnable fix for now, waiting for a deeper refactoring.
This patch must be backported with the commit above.
(cherry picked from commit cea1379cf1fcd5fd9c3b3b104f4c5374bc44bce2)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
During zero-copy data forwarding, the producer must set the EOI flag on the SE
when end of the message is reached. It is already done but there is a case where
this flag is set while it should not. When a request wants to perform a protocol
upgrade and it is waiting for the server response, the flag must not be set
because the HTTP message is finished but some data are possibly still expected,
depending on the server response. On a 101-switching-protocol, more data will be
sent because the producer is switch to TUNNEL state.
So, now, the right condition is used. In DONE state, SE_FL_EOI flag is set on the sedesc iff:
- it is the response
- it is the request and the response is also in DONNE state
- it is a request but no a protocol upgrade nor a CONNECT
This patch must be backported as far as 2.9.
(cherry picked from commit 6b39e245e1d58698310fbb06b8122423232be9a4)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
An interesting bug was revealed by commit 5541d4995d ("BUG/MEDIUM: queue:
deal with a rare TOCTOU in assign_server_and_queue()"). When shutting
down a server to redistribute its connections, no check is made on the
backend's queue. If we're turning off the last server and the backend
has pending connections, these ones will wait there till the queue
timeout. But worse, since the commit above, we can enter an endless loop
in the following situation:
- streams are present in the backend's queue
- streams are purged on the last server via srv_shutdown_streams()
- that one calls pendconn_redistribute(srv) which does not purge
the backend's pendconns
- a stream performs some load balancing and enters assign_server_and_queue()
- assign_server() is called in turn
- the LB algo is non-deterministic and there are entries in the
backend's queue. The function notices it and returns SRV_STATUS_FULL
- assign_server_and_queue() calls pendconn_add() to add the connection
to the backend's queue
- on return, pendconn_must_try_again() is called, it figures there's
no stream served anymore on the server nor the proxy, so it removes
the pendconn from the queue and returns 1
- assign_server_and_queue() loops back to the beginning to try again,
while the conditions have not changed, resulting in an endless loop.
Ideally a change count should be used in the queues so that it's possible
to detect that some dequeuing happened and/or that a last stream has left.
But that wouldn't completely solve the problem that is that we must never
ever add to a queue when there's no server streams to dequeue the new
entries.
The current solution consists in making pendconn_redistribute() take care
of the proxy after the server in case there's no more server available on
the proxy. It at least ensures that no pending streams are left in the
backend's queue when shutting streams down or when the last server goes
down. The try_again loop remains necessary to deal with inevitable races
during pendconn additions. It could be limited to a few rounds, though,
but it should never trigger if the conditions are sufficient to permit
it to converge.
One way to reproduce the issue is to run a config with a single server
with maxconn 1 and plenty of threads, then run in loops series of:
"disable server px/s;shutdown sessions server px/s;
wait 100ms server-removable px/s; show servers conn px;
enable server px/s"
on the CLI at ~10/s while injecting with around 40 concurrent conns at
40-100k RPS. In this case in 10s - 1mn the crash can appear with a
backtrace like this one for at least 1 thread:
#0 pendconn_add (strm=strm@entry=0x17f2ce0) at src/queue.c:487
#1 0x000000000064797d in assign_server_and_queue (s=s@entry=0x17f2ce0) at src/backend.c:1064
#2 0x000000000064a928 in srv_redispatch_connect (s=s@entry=0x17f2ce0) at src/backend.c:1962
#3 0x000000000064ac54 in back_handle_st_req (s=s@entry=0x17f2ce0) at src/backend.c:2287
#4 0x00000000005ae1d5 in process_stream (t=t@entry=0x17f4ab0, context=0x17f2ce0, state=<optimized out>) at src/stream.c:2336
It's worth noting that other threads may often appear waiting after the
poller and one in server_atomic_sync() waiting for isolation, because
the event that is processed when shutting the server down is consumed
under isolation, and having less threads available to dequeue remaining
requests increases the probability to trigger the problem, though it is
not at all necessary (some less common traces never show them).
This should carefully be backported wherever the commit above was
backported.
(cherry picked from commit 53f52e67a08fc2cd5ae64caf4148a5de884f9959)
Signed-off-by: Willy Tarreau <w@1wt.eu>
When shutting down server sessions, the queue was not considered, which
is a problem if some element reached the queue at the moment the server
was going down, because there will be no more requests to kick them out
of it. Let's always make sure we scan the queue to kick these streams
out of it and that they can possibly find a more suitable server. This
may make a difference in the time it takes to shut down a server on the
CLI when lots of servers are in the queue.
It might be interesting to backport this to 3.0 but probably not much
further.
(cherry picked from commit 1d403caf8aa59c9070f30ea16017261cab679fe2)
Signed-off-by: Willy Tarreau <w@1wt.eu>
Turning a server to maintenance currently doesn't redispatch the server
queue unless there's an explicit "option redispatch" and no "option
persist", while the former has never really been the purpose of this
test. Better refine this so that forced maintenance also causes the
queue to be flushed, and possibly redispatched unless the proxy has
option persist. This way now when turning a server to maintenance,
the queue is immediately flushed and streams can decide what to do.
This can be backported, though there's no need to go far since it was
never directly reported and only noticed as part of debugging some
rare "shutdown sessions" strangeness, which it might participate to.
(cherry picked from commit 1385e33eb089093dbc970dbc2759d2969ae533c5)
Signed-off-by: Willy Tarreau <w@1wt.eu>
The solution found in commit b500e84e24 ("BUG/MINOR: server: shut down
streams under thread isolation") to deal with inter-thread stream
shutdown doesn't work fine because there exists code paths involving
a server lock which can then deadlock on thread_isolate(). A better
solution then consists in deferring the shutdown to the stream itself
and just wake it up for that.
The only thing is that TASK_WOKEN_OTHER is a bit too generic and we
need to pass at least 2 types of events (SF_ERR_DOWN and SF_ERR_KILLED),
so we're now leveraging the new TASK_F_UEVT1 and _UEVT2 flags on the
task's state to convey these info. The caller only needs to wake the
task up with these flags set, and the stream handler will then finish
the job locally using stream_shutdown_self().
This needs to be carefully backported to all branches affected by the
dequeuing issue and containing any of the 5541d4995d ("BUG/MEDIUM:
queue: deal with a rare TOCTOU in assign_server_and_queue()"), and/or
b11495652e ("BUG/MEDIUM: queue: implement a flag to check for the
dequeuing").
(cherry picked from commit b8e3b0a18d59b4f52b4ecb7ae61cef0b8b2402a0)
Signed-off-by: Willy Tarreau <w@1wt.eu>
TASK_WOKEN_MSG only says "someone sent you a message" but doesn't convey
any info about the message. TASK_WOKEN_OTHER says "you're woken for another
reason" but doesn't tell which one. Most often they're used as-is by the
task handlers to report very specific situations.
For some important control notifications, having the ability to modulate
the message a little bit is useful, so let's define two user event types
UEVT1 and UEVT2 to be used in conjunction with TASK_WOKEN_MSG or _OTHER
so that the application can know that a specific condition was explicitly
requested. It will be used this way:
task_wakeup(s->task, TASK_WOKEN_MSG | TASK_F_UEVT1);
or:
task_wakeup(s->task, TASK_WOKEN_OTHER | TASK_F_UEVT2);
Since events are cumulative, keep in mind not to consider a 3rd value
as the combination of EVT1+EVT2; these really mean that the two events
appeared (though in unspecified order).
(cherry picked from commit b5281283bb00248152ba361f8d7306b37febbee0)
Signed-off-by: Willy Tarreau <w@1wt.eu>
The function is provided by glibc. Nothing prevents us from using our
own outside of glibc there (tested on aarch64 with musl). We still do
not enable it by default as we don't yet know if all archs work well,
but it's sufficient to pass USE_BACKTRACE=1 when building with musl to
verify it's OK.
(cherry picked from commit 7caf073faa6962de15a18dadcaf200df95ce7889)
Signed-off-by: Willy Tarreau <w@1wt.eu>
No need to include this possibly non-existing file when using our own
backtrace() implementation, it's only needed for the libc-provided one.
Because of this it's currently not possible to build musl with backtrace
enabled.
(cherry picked from commit 1c4776dbc3e7d0a73bd62bae78d509c3c54045d6)
Signed-off-by: Willy Tarreau <w@1wt.eu>
Keywords setenv and presetenv take 2 arguments: variable name and value.
So, the total number, that should be passed to alertif_too_many_args is 2
("setenv <name> <value>") instead of 3. For alertif_too_many_args the first
argument index is 0.
This should be backported in all stable versions.
(cherry picked from commit df68f7ec96c0c9d0e8f50643b96ec9062b7aa658)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
In 1.8 when adding "set server fqdn" with commit b418c1228c ("MINOR:
server: cli: Add server FQDNs to server-state file and stats socket."),
the HMAINT flag was not made part of the MAINT ones, so technically
speaking when changing the FQDN, the server is not completely considered
as in maintenance mode.
In its defense, the code location around that was completely messy, with
the aggregator flag being hidden between other values and purposely but
discretely ignoring one of the flags, so the comments were updated to
make the intent clearer (particularly regarding CMAINT which looked like
it was also forgotten while it was on purpose).
This can be backported anywhere.
(cherry picked from commit a4d04c649af448cf2a728ebb91837ed69eea6217)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
The proxy lock state isn't passed down to relax_listener
through dequeue_proxy_listeners, which causes a deadlock
in relax_listener when it tries to get that lock.
Backporting: Older versions didn't have relax_listener and directly called
resume_listener in dequeue_proxy_listeners. lpx should just be passed directly
to resume_listener then.
The bug was introduced in commit 001328873c
[cf: This patch should fix the issue #2726. It must be backported as far as
2.4]
(cherry picked from commit a889413f5ec5e2c0c6ed30debfd16f666dbc0f99)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
A client abort while nothing was sent is properly handled except when this
immediately happens after the connection was accepted. The read0 event is
caught before the CLI applet is created. In that case, the shutdown is not
handled and the applet is no longer wakeup. In that case, the stream remains
blocked and no timeout are armed.
The bug was due to the fact that when the applet I/O handler was called for
the first time, the applet context was initialized and nothing more was
performed. A shutdown, if any, would be handled on the next call. In that
case, it was too late.
Now, afet the init step, we loop to eval the first command. There is no
command here but the shutdown will be tested.
This patch should fix the issue #2727. It must be backported to 3.0.
(cherry picked from commit 14a413033c15aa4622368348ac6b142e7ec2c989)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
