sess_log() was called twice if an error occurred on the preface parsing, in
h2c_frt_recv_preface() and in h2_process_demux().
This patch must be backported as far as 2.0.
The fix in commit 7b0e00d94 ("BUG/MINOR: http_fetch: make hdr_ip() reject
trailing characters") made hdr_ip() more sensitive to empty fields, for
example if a trusted proxy incorrectly sends the header with an empty
value, we could return 0.0.0.0 which is not correct. Let's make sure we
only assign an IPv4 type here when a non-empty address was found.
This should be backported to all branches where the fix above was
backported.
Historically we've used SOL_IP/SOL_IPV6/SOL_TCP everywhere as the socket
level value in getsockopt() and setsockopt() but as we've seen over time
it regularly broke the build and required to have them defined to their
IPPROTO_* equivalent. The Linux ip(7) man page says:
Using the SOL_IP socket options level isn't portable; BSD-based
stacks use the IPPROTO_IP level.
And it indeed looks like a pure linuxism inherited from old examples and
documentation. strace also reports SOL_* instead of IPPROTO_*, which does
not help... A check to linux/in.h shows they have the same values. Only
SOL_SOCKET and other non-IP values make sense since there is no IPPROTO
equivalent.
Let's get rid of this annoying confusion by removing all redefinitions of
SOL_IP/IPV6/TCP and using IPPROTO_* instead, just like any other operating
system. This also removes duplicated tests for the same value.
Note that this should not result in exposing syscalls to other OSes
as the only ones that were still conditionned to SOL_IPV6 were for
IPV6_UNICAST_HOPS which already had an IPPROTO_IPV6 equivalent, and
IPV6_TRANSPARENT which is Linux-specific.
Lukas reported in issue #1203 that the previous fix for silent-drop in
commit ab79ee8b1 ("BUG/MINOR: tcp: fix silent-drop workaround for IPv6")
breaks the build on FreeBSD/MacOS due to SOL_IPV6 not being defined. On
these platforms, IPPROTO_IPV6 must be used instead, so this should fix
it.
This needs to be backported to whatever version the fix above is backported
to.
As reported in github issue #1203 the TTL-based workaround that is used
when permissions are insufficient for the TCP_REPAIR trick does not work
for IPv6 because we're using only SOL_IP with IP_TTL. In IPv6 we have to
use SOL_IPV6 and IPV6_UNICAST_HOPS. Let's pick the right one based on the
source address's family.
This may be backported to all versions.
The issue with non-rotating freq counters was addressed in commit 8cc586c73
("BUG/MEDIUM: freq_ctr/threads: use the global_now_ms variable") using the
global date. But an issue remained with the comparison of the most recent
time. Since the initial time in the structure is zero, the tick_is_lt()
works on half of the periods depending on the first date an entry is
touched. And the wrapping happened last night:
$ date --date=@$(((($(date +%s) * 1000) & -0x8000000) / 1000))
Mon Mar 29 23:59:46 CEST 2021
So users of the last fix (backported to 2.3.8) may experience again an
always increasing rate for the next 24 days if they restart their process.
Let's always update the time if the latest date was not updated yet. It
will likely be simplified once the function is reorganized but this will
do the job for now.
Note that since this timer is only used by freq counters, no other
sub-system is affected. The bug can easily be tested with this config
during the right time period (i.e. today to today+24 days + N*49.7 days):
global
stats socket /tmp/sock1
frontend web
bind :8080
mode http
http-request track-sc0 src
stick-table type ip size 1m expire 1h store http_req_rate(2s)
Issuing 'socat - /tmp/sock1 <<< "show table web"' should show a stable
rate after 2 seconds.
The fix must be backported to 2.3 and any other version the fix above
goes into.
Thanks to Thomas SIMON and Sander Klein for quickly reporting this issue
with a working reproducer.
When a backend is in status DOWN and going UP it is currently displayed
as yellow ("active UP, going down") instead of orange ("active DOWN, going
UP"). This patches restyles the table rows to actually match the
legend.
This may be backported to any version, the issue appeared in 1.7-dev2
with commit 0c378efe8 ("MEDIUM: stats: compute the color code only in
the HTML form").
In payload() and payload_lv() sample fetches, if the buffer is empty, we
must wait for more data by setting SMP_F_MAY_CHANGE flag on the sample.
Otherwise, when it happens in an ACL, nothing is returned (because the
buffer is empty) and the ACL is considered as finished (success or failure
depending on the test).
As a workaround, the buffer length may be tested first. For instance :
tcp-request inspect-delay 1s
tcp-request content reject unless { req.len gt 0 } { req.payload(0,0),fix_is_valid }
instead of :
tcp-request inspect-delay 1s
tcp-request content reject if ! { req.payload(0,0),fix_is_valid }
This patch must be backported as far as 2.2.
Released version 2.4-dev14 with the following main changes :
- MEDIUM: quic: Fix build.
- MEDIUM: quic: Fix build.
- CI: codespell: whitelist "Dragan Dosen"
- CLEANUP: assorted typo fixes in the code and comments
- CI: github actions: update LibreSSL to 3.2.5
- REGTESTS: revert workaround for a crash with recent libressl on http-reuse sni
- CLEANUP: mark defproxy as const on parse tune.fail-alloc
- REGTESTS: remove unneeded experimental-mode in cli add server test
- REGTESTS: wait for proper return of enable server in cli add server test
- MINOR: compression: use pool_alloc(), not pool_alloc_dirty()
- MINOR: spoe: use pool_alloc(), not pool_alloc_dirty()
- MINOR: fcgi-app: use pool_alloc(), not pool_alloc_dirty()
- MINOR: cache: use pool_alloc(), not pool_alloc_dirty()
- MINOR: ssl: use pool_alloc(), not pool_alloc_dirty()
- MINOR: opentracing: use pool_alloc(), not pool_alloc_dirty()
- MINOR: dynbuf: make b_alloc() always check if the buffer is allocated
- CLEANUP: compression: do not test for buffer before calling b_alloc()
- CLEANUP: l7-retries: do not test the buffer before calling b_alloc()
- MINOR: channel: simplify the channel's buffer allocation
- MEDIUM: dynbuf: remove last usages of b_alloc_margin()
- CLEANUP: dynbuf: remove b_alloc_margin()
- CLEANUP: dynbuf: remove the unused b_alloc_fast() function
- CLEANUP: pools: remove the unused pool_get_first() function
- MINOR: pools: make the pool allocator support a few flags
- MINOR: pools: add pool_zalloc() to return a zeroed area
- CLEANUP: connection: use pool_zalloc() in conn_alloc_hash_node()
- CLEANUP: filters: use pool_zalloc() in flt_stream_add_filter()
- CLEANUP: spoe: use pool_zalloc() instead of pool_alloc+memset
- CLEANUP: frontend: use pool_zalloc() in frontend_accept()
- CLEANUP: mailers: use pool_zalloc() in enqueue_one_email_alert()
- CLEANUP: resolvers: use pool_zalloc() in resolv_link_resolution()
- CLEANUP: ssl: use pool_zalloc() in ssl_init_keylog()
- CLEANUP: tcpcheck: use pool_zalloc() instead of pool_alloc+memset
- CLEANUP: quic: use pool_zalloc() instead of pool_alloc+memset
- MINOR: time: also provide a global, monotonic global_now_ms timer
- BUG/MEDIUM: freq_ctr/threads: use the global_now_ms variable
- MINOR: tools: introduce new option PA_O_DEFAULT_DGRAM on str2sa_range.
- BUILD: tools: fix build error with new PA_O_DEFAULT_DGRAM
- BUG/MINOR: ssl: Prevent disk access when using "add ssl crt-list"
- CLEANUP: ssl: remove unused definitions
- BUILD: ssl: guard ecdh functions with SSL_CTX_set_tmp_ecdh macro
- MINOR: lua: Slightly improve function dumping the lua traceback
- BUG/MEDIUM: debug/lua: Use internal hlua function to dump the lua traceback
- BUG/MEDIUM: lua: Always init the lua stack before referencing the context
- MINOR: fd: make fd_clr_running() return the remaining running mask
- MINOR: fd: remove the unneeded running bit from fd_insert()
- BUG/MEDIUM: fd: do not wait on FD removal in fd_delete()
- CLEANUP: fd: remove unused fd_set_running_excl()
- CLEANUP: fd: slightly simplify up _fd_delete_orphan()
- BUG/MEDIUM: fd: Take the fd_mig_lock when closing if no DWCAS is available.
- BUG/MEDIUM: release lock on idle conn killing on reached pool high count
- BUG/MEDIUM: thread: Fix a deadlock if an isolated thread is marked as harmless
- MINOR: tools: make url2ipv4 return the exact number of bytes parsed
- BUG/MINOR: http_fetch: make hdr_ip() reject trailing characters
- BUG/MEDIUM: mux-h1: make h1_shutw_conn() idempotent
- BUG/MINOR: ssl: Fix update of default certificate
- BUG/MINOR: ssl: Prevent removal of crt-list line if the instance is a default one
- BUILD: ssl: introduce fine guard for ssl random extraction functions
- REORG: global: move initcall register code in a dedicated file
- REORG: global: move free acl/action in their related source files
- REORG: split proxy allocation functions
- MINOR: proxy: implement a free_proxy function
- MINOR: proxy: define cap PR_CAP_LUA
- MINOR: lua: properly allocate the lua Socket proxy
- MINOR: lua: properly allocate the lua Socket servers
- MINOR: vars: make get_vars() allow the session to be null
- MINOR: vars: make the var() sample fetch keyword depend on nothing
- CLEANUP: sample: remove duplicate "stopping" sample fetch keyword
- MINOR: sample: make smp_resolve_args() return an allocate error message
- MINOR: sample: add a new SMP_SRC_CONST sample capability
- MINOR: sample: mark the truly constant sample fetch keywords as such
- MINOR: sample: add a new CFG_PARSER context for samples
- MINOR: action: add a new ACT_F_CFG_PARSER origin designation
- MEDIUM: vars: add support for a "set-var" global directive
- REGTESTS: add a basic reg-test for some "set-var" commands
- MINOR: sample: add a new CLI_PARSER context for samples
- MINOR: action: add a new ACT_F_CLI_PARSER origin designation
- MINOR: vars/cli: add a "get var" CLI command to retrieve global variables
- MEDIUM: cli: add a new experimental "set var" command
- MINOR: compat: add short aliases for a few very commonly used types
- BUILD: ssl: use EVP_CIPH_GCM_MODE macro instead of HA_OPENSSL_VERSION
- MEDIUM: backend: use a trylock to grab a connection on high FD counts as well
Commit b1adf03df ("MEDIUM: backend: use a trylock when trying to grab an
idle connection") solved a contention issue on the backend under normal
condition, but there is another one further, which only happens when the
number of FDs in use is considered too high, and which obviously causes
random crashes with just 16 threads once the number of FDs is about to be
exhausted.
Like the aforementioned patch, this one should be backported to 2.3.
Very often we use "int" where negative numbers are not needed (and can
further cause trouble) just because it's painful to type "unsigned int"
or "unsigned", or ugly to use in function arguments. Similarly sometimes
chars would absolutely need to be signed but nobody types "signed char".
Let's add a few aliases for such types and make them part of the standard
internal API so that over time we can get used to them and get rid of
horrible definitions. A comment also reminds some commonly available
types and their properties regarding other types.
set var <name> <expression>
Allows to set or overwrite the process-wide variable 'name' with the result
of expression <expression>. Only process-wide variables may be used, so the
name must begin with 'proc.' otherwise no variable will be set. The
<expression> may only involve "internal" sample fetch keywords and converters
even though the most likely useful ones will be str('something') or int().
Note that the command line parser doesn't know about quotes, so any space in
the expression must be preceeded by a backslash. This command requires levels
"operator" or "admin". This command is only supported on a CLI connection
running in experimental mode (see "experimental-mode on").
Just like for "set-var" in the global section, the command uses a temporary
dummy proxy to create a temporary "set-var(name)" rule to assign the value.
The reg test was updated to verify that an updated global variable is properly
reflected in subsequent HTTP responses.
Process-wide variables can now be displayed from the CLI using "get var"
followed by the variable name. They must all start with "proc." otherwise
they will not be found. The output is very similar to the one of the
debug converter, with a type and value being reported for the embedded
sample.
This command is limited to clients with the level "operator" or higher,
since it can possibly expose traffic-related data.
In order to process samples from the command line interface we'll need
rules as well, and these rules will have to be marked as coming from
the CLI parser. This new origin is used for this.
In order to prepare for supporting calling sample expressions from the
CLI, let's create a new CLI_PARSER parsing context. This one supports
constants and internal samples only.
This reg-test tests "set-var" in the global section, with some overlapping
variables and using a few samples and converters, then at the TCP and HTTP
levels using proc/sess/req variables.
While we do support process-wide variables ("proc.<name>"), there was
no way to preset them from the configuration. This was particularly
limiting their usefulness since configs involving them always had to
first check if the variable was set prior to performing an operation.
This patch adds a new "set-var" directive in the global section that
supports setting the proc.<name> variables from an expression, like
other set-var actions do. The syntax however follows what is already
being done for setenv, which consists in having one argument for the
variable name and another one for the expression.
Only "constant" expressions are allowed here, such as "int", "str"
etc, combined with arithmetic or string converters, and variable
lookups. A few extra sample fetch keywords like "date", "rand" and
"uuid" are also part of the constant expressions and may make sense
to allow to create a random key or differentiate processes.
The way it was done consists in parsing a dummy rule an executing the
expression in the CFG_PARSE context, then releasing the expression.
This is safe because the sample that variables store does not hold a
back pointer to expression that created them.
In order to process samples from the config file we'll need rules as
well, and these rules will have to be marked as coming from the
config parser. This new origin is used for this.
We'd sometimes like to be able to process samples while parsing
the configuration based on purely internal thing but that's not
possible right now. Let's add a new CFG_PARSER context for samples
which only permits constant samples (i.e. those which do not change
in the process' life and which are stable during config parsing).
A number of keywords are really constant and safe to use at config
time. This is the case for str(), int() etc but also env(), hostname(),
nbproc() etc. By extension a few other ones which can be useful to
preset values in a configuration were enabled as well, like data(),
rand() or uuid(). At the moment this doesn't change anything as they
are still only usable from runtime rules.
The "var()" keyword was also marked as const as it can definitely
return stable stuff at boot time.
This level indicates that everything it constant in the expression during
the whole process' life and that it may safely be used at config parsing
time.
For now smp_resolve_args() complains on stderr via ha_alert(), but if we
want to make it a bit more dynamic, we need it to return errors in an
allocated message. Let's pass it an error pointer and have it fill it.
On return we indent the output if it contains more than one line.
The "stopping" sample fetch keyword was accidently duplicated in 1.9
by commit 70fe94419 ("MINOR: sample: add cpu_calls, cpu_ns_avg,
cpu_ns_tot, lat_ns_avg, lat_ns_tot"). This has no effect so no
backport is needed.
This sample fetch doesn't require any L4 client session in practice, as
get_var() now checks for the session. This is important to remove this
dependency in order to support accessing variables in scope "proc" from
anywhere.
Instantiate both lua Socket servers tcp/ssl using standard function
new_server. There is currently no need to tune their settings except to
activate the ssl mode with noverify for the second one. Both servers are
freed with the free_server function.
Replace static initialization of the lua Socket proxy with the standard
function alloc_new_proxy. The settings proxy are properly applied thanks
to PR_CAP_LUA. The proxy is freed with the free_proxy function.
Define a new cap PR_CAP_LUA. It can be used to allocate the internal
proxy for lua Socket class. This cap overrides default settings for
preferable values in the lua context.
Move all liberation code related to a proxy in a dedicated function
free_proxy in proxy.c. For now, this function is only called in
haproxy.c. In the future, it will be used to free the lua proxy.
This helps to clean up haproxy.c.
Create a new function parse_new_proxy specifically designed to allocate
a new proxy from the configuration file and copy settings from the
default proxy.
The function alloc_new_proxy is reduced to a minimal allocation. It is
used for default proxy allocation and could also be used for internal
proxies such as the lua Socket proxy.
Move deinit_acl_cond and deinit_act_rules from haproxy.c respectively in
acl.c and action.c. The name of the functions has been slightly altered,
replacing the prefix deinit_* by free_* to reflect their purpose more
clearly.
This change has been made in preparation to the implementation of a free
proxy function. As a side-effect, it helps to clean up haproxy.c.
Create a new module init which contains code related to REGISTER_*
macros for initcalls. init.h is included in api.h to make init code
available to all modules.
It's a step to clean up a bit haproxy.c/global.h.
If the first active line of a crt-list file is also the first mentioned
certificate of a frontend that does not have the strict-sni option
enabled, then its certificate will be used as the default one. We then
do not want this instance to be removable since it would make a frontend
lose its default certificate.
Considering that a crt-list file can be used by multiple frontends, and
that its first mentioned certificate can be used as default certificate
for only a subset of those frontends, we do not want the line to be
removable for some frontends and not the others. So if any of the ckch
instances corresponding to a crt-list line is a default instance, the
removal of the crt-list line will be forbidden.
It can be backported as far as 2.2.
The default SSL_CTX used by a specific frontend is the one of the first
ckch instance created for this frontend. If this instance has SNIs, then
the SSL context is linked to the instance through the list of SNIs
contained in it. If the instance does not have any SNIs though, then the
SSL_CTX is only referenced by the bind_conf structure and the instance
itself has no link to it.
When trying to update a certificate used by the default instance through
a cli command, a new version of the default instance was rebuilt but the
default SSL context referenced in the bind_conf structure would not be
changed, resulting in a buggy behavior in which depending on the SNI
used by the client, he could either use the new version of the updated
certificate or the original one.
This patch adds a reference to the default SSL context in the default
ckch instances so that it can be hot swapped during a certificate
update.
This should fix GitHub issue #1143.
It can be backported as far as 2.2.
In issue #1197, Stéphane Graber reported a rare case of crash that
results from an attempt to close an already closed H1 connection. It
indeed looks like under some circumstances it should be possible to
call the h1_shutw_conn() function more than once, though these
conditions are not very clear.
Without going through a deep analysis of all possibilities, one
potential case seems to be a detach() called with pending output data,
causing H1C_F_ST_SHUTDOWN to be set on the connection, then h1_process()
being immediately called on I/O, causing h1_send() to flush these data
and call h1_shutw_conn(), and finally the upper stream calling cs_shutw()
hence h1_shutw(), which itself will call h1_shutw_conn() again while the
transport and control layers have already been released. But the whole
sequence is not certain as it's not very clear in which case it's
possible to leave h1_send() without the connection anymore (at least
the obuf is empty).
However what is certain is that a shutdown function must be idempotent,
so let's fix h1_shutw_conn() regarding this point. Stéphane reported the
issue as far back as 2.0, so this patch should be backported this far.
The hdr_ip() sample fetch function will try to extract IP addresses
from a header field. These IP addresses are parsed using url2ipv4()
and if it fails it will fall back to inet_pton(AF_INET6), otherwise
will fail.
There is a small problem there which is that if a field starts with
an IP address and is immediately followed by some garbage, the IP
address part is still returned. This is a problem with fields such
as x-forwarded-for because it prevents detection of accidental
corruption or bug along the chain. For example, the following string:
x-forwarded-for: 1.2.3.4; 5.6.7.8
or this one:
x-forwarded-for: 1.2.3.4O ( the last one being the letter 'O')
would still return "1.2.3.4" despite the trailing characters. This is
bad because it will silently cover broken code running on intermediary
proxies and may even in some cases allow haproxy to pass improperly
formatted headers after they were apparently validated, for example,
if someone extracts the address from this field to place it into
another one.
This issue would only affect the IPv4 parser, because the IPv6 parser
already uses inet_pton() which fails at the first invalid character and
rejects trailing port numbers.
In strict compliance with RFC7239, let's make sure that if there are any
characters left in the string, the parsing fails and makes hdr_ip()
return nothing. However, a special case has to be handled to support
IPv4 addresses followed by a colon and a valid port number, because till
now the parser used to implicitly accept them and it appears that this
practice, though rare, does exist at least in Azure:
https://docs.microsoft.com/en-us/azure/application-gateway/how-application-gateway-works
This issue has always been there so the fix may be backported to all
versions. It will need the following commit in order to work as expected:
MINOR: tools: make url2ipv4 return the exact number of bytes parsed
Many thanks to https://twitter.com/melardev and the BitMEX Security Team
for their detailed report.
The function's return value is currently used as a boolean but we'll
need it to return the number of bytes parsed. Right now it returns
it minus one, unless the last char doesn't match what is permitted.
Let's update this to make it more usable.
If an isolated thread is marked as harmless, it will loop forever in
thread_harmless_till_end() waiting no threads are isolated anymore. It never
happens because the current thread is isolated. To fix the bug, we exclude
the current thread for the test. We now wait for all other threads to leave
the rendez-vous point.
This bug only seems to occurr if HAProxy is compiled with DEBUG_UAF, when
pool_gc() is called. pool_gc() isolates the current thread, while
pool_free_area() set the thread as harmless when munmap is called.
This patch must be backported as far as 2.0.
Release the lock before calling mux destroy in connect_server when
trying to kill an idle connection because the pool high count has been
reached.
The lock must be released because the mux destroy will call
srv_release_conn which also takes the lock to remove the connection from
the tree. As the connection was already deleted from the tree at this
stage, it is safe to release the lock, and the removal in
srv_release_conn will be a noop.
It does not need to be backported because it is only present in the
current release. It has been introduced by
5c7086f6b0
MEDIUM: connection: protect idle conn lists with locks
In fd_delete(), if we're running with no double-width cas, take the
fd_mig_lock before setting thread_mask to 0 to make sure that
another thread calling fd_set_running() won't miss the new value of
thread_mask and set its bit in running_mask after we checked it.
This should be backported to 2.2 as part of the series fixing fd_delete().
Christopher discovered an issue mostly affecting 2.2 and to a less extent
2.3 and above, which is that it's possible to deadlock a soft-stop when
several threads are using a same listener:
thread1 thread2
unbind_listener() fd_set_running()
lock(listener) listener_accept()
fd_delete() lock(listener)
while (running_mask); -----> deadlock
unlock(listener)
This simple case disappeared from 2.3 due to the removal of some locked
operations at the end of listener_accept() on the regular path, but the
architectural problem is still here and caused by a lock inversion built
around the loop on running_mask in fd_clr_running_excl(), because there
are situations where the caller of fd_delete() may hold a lock that is
preventing other threads from dropping their bit in running_mask.
The real need here is to make sure the last user deletes the FD. We have
all we need to know the last one, it's the one calling fd_clr_running()
last, or entering fd_delete() last, both of which can be summed up as
the last one calling fd_clr_running() if fd_delete() calls fd_clr_running()
at the end. And we can prevent new threads from appearing in running_mask
by removing their bits in thread_mask.
So what this patch does is that it sets the running_mask for the thread
in fd_delete(), clears the thread_mask, thus marking the FD as orphaned,
then clears the running mask again, and completes the deletion if it was
the last one. If it was not, another thread will pass through fd_clr_running
and will complete the deletion of the FD.
The bug is easily reproducible in 2.2 under high connection rates during
soft close. When the old process stops its listener, occasionally two
threads will deadlock and the old process will then be killed by the
watchdog. It's strongly believed that similar situations do exist in 2.3
and 2.4 (e.g. if the removal attempt happens during resume_listener()
called from listener_accept()) but if so, they should be much harder to
trigger.
This should be backported to 2.2 as the issue appeared with the FD
migration. It requires previous patches "fd: make fd_clr_running() return
the remaining running mask" and "MINOR: fd: remove the unneeded running
bit from fd_insert()".
Notes for backport: in 2.2, the fd_dodelete() function requires an extra
argument "do_close" indicating whether we want to remove and close the FD
(fd_delete) or just delete it (fd_remove). While this information is not
conveyed along the chain, we know that late calls always imply do_close=1
become do_close=0 exclusively results from fd_remove() which is only used
by the config parser and the master, both of which are single-threaded,
hence are always the last ones in the running_mask. Thus it is safe to
assume that a postponed FD deletion always implies do_close=1.
Thanks to Olivier for his help in designing this optimal solution.
There's no point taking the running bit in fd_insert() since by
definition there will never be more than one thread inserting the FD,
and that fd_insert() may only be done after the fd was allocated by
the system, indicating the end of use by any other thread.
This will need to be backported to 2.2 to fix an issue.
We'll need to know that a thread is the last one to use an fd, so let's
make fd_clr_running() return the remaining bits after removal. Note that
in practice we're only interested in knowing if it's zero but the compiler
doesn't make use of the clags after the AND and emits a CMPXCHG anyway :-/
This will need to be backported to 2.2 to fix an issue.
When a lua context is allocated, its stack must be initialized to NULL
before attaching it to its owner (task, stream or applet). Otherwise, if
the watchdog is fired before the stack is really created, that may lead to a
segfault because we try to dump the traceback of an uninitialized lua stack.
It is easy to trigger this bug if a lua script do a blocking call while
another thread try to initialize a new lua context. Because of the global
lua lock, the init is blocked before the stack creation. Of course, it only
happens if the script is executed in the shared global context.
This patch must be backported as far as 2.0.
The commit reverts following commits:
* 83926a04 BUG/MEDIUM: debug/lua: Don't dump the lua stack if not dumpable
* a61789a1 MEDIUM: lua: Use a per-thread counter to track some non-reentrant parts of lua
Instead of relying on a Lua function to print the lua traceback into the
debugger, we are now using our own internal function (hlua_traceback()).
This one does not allocate memory and use a chunk instead. This avoids any
issue with a possible deadlock in the memory allocator because the thread
processing was interrupted during a memory allocation.
This patch relies on the commit "BUG/MEDIUM: debug/lua: Use internal hlua
function to dump the lua traceback". Both must be backported wherever the
patches above are backported, thus as far as 2.0
The separator string is now configurable, passing it as parameter when the
function is called. In addition, the message have been slightly changed to
be a bit more readable.
