As mentioned in previous patch, the random number generator was never
made thread-safe, which used not to be a problem for health checks
spreading, until the uuid sample fetch function appeared. Currently
it is possible for two threads or processes to produce exactly the
same UUID. In fact it's extremely likely that this will happen for
processes, as can be seen with this config:
global
nbproc 8
frontend f
bind :4445
mode http
log stdout daemon format raw
log-format "%[uuid] %pid"
redirect location /
It typically produces this log:
551ce567-0bfb-4bbd-9b58-cdc7e9365325 30645
551ce567-0bfb-4bbd-9b58-cdc7e9365325 30641
551ce567-0bfb-4bbd-9b58-cdc7e9365325 30644
551ce567-0bfb-4bbd-9b58-cdc7e9365325 30639
551ce567-0bfb-4bbd-9b58-cdc7e9365325 30646
07764439-c24d-4e6f-a5a6-0138be59e7a8 30645
07764439-c24d-4e6f-a5a6-0138be59e7a8 30639
551ce567-0bfb-4bbd-9b58-cdc7e9365325 30643
07764439-c24d-4e6f-a5a6-0138be59e7a8 30646
b6773fdd-678f-4d04-96f2-4fb11ad15d6b 30646
551ce567-0bfb-4bbd-9b58-cdc7e9365325 30642
07764439-c24d-4e6f-a5a6-0138be59e7a8 30642
What this patch does is to use a distinct per-thread and per-process
seed to make sure the same sequences will not appear, and will then
extend these seeds by "burning" a number of randoms that depends on
the global random seed, the thread ID and the process ID. This adds
roughly 20 extra bits of randomness, resulting in 52 bits total per
thread and per process.
It only takes a few milliseconds to burn these randoms and given
that threads start with a different seed, we know they will not
catch each other. So these random extra bits are essentially added
to ensure randomness between boots and cluster instances.
This replaces all uses of random() with ha_random() which uses the
thread-local state.
This must be backported as far as 2.0 or any version having the
UUID sample-fetch function since it's the main victim here.
It's important to note that this patch, in addition to depending on
the previous one "BUG/MEDIUM: init: initialize the random pool a bit
better", also depends on the preceeding build fixes to address a
circular dependency issue in the include files that prevented it
from building. Part or all of these patches may need to be backported
or adapted as well.
The htx_find_offset() function may be used to look for a block at a specific
offset in an HTX message, starting from the message head. A compound result is
returned, an htx_ret structure, with the found block and the position of the
offset in the block. If the offset is ouside of the HTX message, the returned
block is NULL.
The b_insert_blk() function may now be used to insert a string, given a pointer
and the string length, at an absolute offset in a buffer, moving data between
this offset and the buffer's tail just after the end of the inserted string. The
buffer's length is automatically updated. This function supports wrapping. All
the string is copied or nothing. So it returns 0 if there are not enough space
to perform the copy. Otherwise, the number of bytes copied is returned.
`istalloc` allocates memory and returns an `ist` with the size `0` that points
to this allocation.
`istfree` frees the pointed memory and clears the pointer.
A test on FreeBSD with clang 4 to 8 produces this on a call to a
spinning loop on the CLI:
call trace(5):
| 0x53e2bc [eb 16 48 63 c3 48 c1 e0]: wdt_handler+0x10c
| 0x800e02cfe [e8 5d 83 00 00 8b 18 8b]: libthr:pthread_sigmask+0x53e
with our own function it correctly produces this:
call trace(20):
| 0x53e2dc [eb 16 48 63 c3 48 c1 e0]: wdt_handler+0x10c
| 0x800e02cfe [e8 5d 83 00 00 8b 18 8b]: libthr:pthread_sigmask+0x53e
| 0x800e022bf [48 83 c4 38 5b 41 5c 41]: libthr:pthread_getspecific+0xdef
| 0x7ffffffff003 [48 8d 7c 24 10 6a 00 48]: main+0x7fffffb416f3
| 0x801373809 [85 c0 0f 84 6f ff ff ff]: libc:__sys_gettimeofday+0x199
| 0x801373709 [89 c3 85 c0 75 a6 48 8b]: libc:__sys_gettimeofday+0x99
| 0x801371c62 [83 f8 4e 75 0f 48 89 df]: libc:gettimeofday+0x12
| 0x51fa0a [48 89 df 4c 89 f6 e8 6b]: ha_thread_dump_all_to_trash+0x49a
| 0x4b723b [85 c0 75 09 49 8b 04 24]: mworker_cli_sockpair_new+0xd9b
| 0x4b6c68 [85 c0 75 08 4c 89 ef e8]: mworker_cli_sockpair_new+0x7c8
| 0x532f81 [4c 89 e7 48 83 ef 80 41]: task_run_applet+0xe1
So let's add clang+x86_64 to the list of platforms that will use our
simplified version. As a bonus it will not require to link with
-lexecinfo on FreeBSD and will work out of the box when passing
USE_BACKTRACE=1.
It happens that on aarch64 backtrace() only returns one entry (tested
with gcc 4.7.4, 5.5.0 and 7.4.1). Probably that it refrains from unwinding
the stack due to the risk of hitting a bad pointer. Here we can use
may_access() to know when it's safe, so we can actually unwind the stack
without taking risks. It happens that the faulting function (the one
just after the signal handler) is not listed here, very likely because
the signal handler uses a special stack and did not create a new frame.
So this patch creates a new my_backtrace() function in standard.h that
either calls backtrace() or does its own unrolling. The choice depends
on HA_HAVE_WORKING_BACKTRACE which is set in compat.h based on the build
target.
We use various hacks at a few places to try to identify known function
pointers in debugging outputs (show threads & show fd). Let's centralize
this into a new function dedicated to this. It already knows about the
functions matched by "show threads" and "show fd", and when built with
USE_DL, it can rely on dladdr1() to resolve other functions. There are
some limitations, as static functions are not resolved, linking with
-rdynamic is mandatory, and even then some functions will not necessarily
appear. It's possible to do a better job by rebuilding the whole symbol
table from the ELF headers in memory but it's less portable and the gains
are still limited, so this solution remains a reasonable tradeoff.
This function dumps <n> bytes from <addr> in hex form into buffer <buf>
enclosed in brackets after the address itself, formatted on 14 chars
including the "0x" prefix. This is meant to be used as a prefix for code
areas. For example: "0x7f10b6557690 [48 c7 c0 0f 00 00 00 0f]: "
It relies on may_access() to know if the bytes are dumpable, otherwise "--"
is emitted. An optional prefix is supported.
This lock was only needed to protect the buffer_wq list, but now we have
the mt_list for this. This patch simply turns the buffer_wq list to an
mt_list and gets rid of the lock.
It's worth noting that the whole buffer_wait thing still looks totally
wrong especially in a threaded context: the wakeup_cb() callback is
called synchronously from any thread and may end up calling some
connection code that was not expected to run on a given thread. The
whole thing should probably be reworked to use tasklets instead and be
a bit more centralized.
This commit adds ALWAYS_ALIGN(), MAYBE_ALIGN() and ATOMIC_ALIGN() to
be placed as delimitors inside structures to force alignment to a
given size. These depend on the architecture's capabilities so that
it is possible to always align, align only on archs not supporting
unaligned accesses at all, or only on those not supporting them for
atomic accesses (e.g. before a lock).
The isalnum(), isalpha(), isdigit() etc functions from ctype.h are
supposed to take an int in argument which must either reflect an
unsigned char or EOF. In practice on some platforms they're implemented
as macros referencing an array, and when passed a char, they either cause
a warning "array subscript has type 'char'" when lucky, or cause random
segfaults when unlucky. It's quite unconvenient by the way since none of
them may return true for negative values. The recent introduction of
cygwin to the list of regularly tested build platforms revealed a lot
of breakage there due to the same issues again.
So this patch addresses the problem all over the code at once. It adds
unsigned char casts to every valid use case, and also drops the unneeded
double cast to int that was sometimes added on top of it.
It may be backported by dropping irrelevant changes if that helps better
support uncommon platforms. It's unlikely to fix bugs on platforms which
would already not emit any warning though.
This used to be a minor optimization on ix86 where registers are scarce
and the calling convention not very efficient, but this platform is not
relevant enough anymore to warrant all this dirt in the code for the sake
of saving 1 or 2% of performance. Modern platforms don't use this at all
since their calling convention already defaults to using several registers
so better get rid of this once for all.
This patch turns the double negation of 'not unlikely' into 'likely'
and then turns the negation of 'not smaller' into 'greater or equal'
in an attempt to improve readability of the condition.
[wt: this was not a bug but purposely written like this to improve code
generation on older compilers but not needed anymore as described here:
https://www.mail-archive.com/haproxy@formilux.org/msg36392.html ]
We used to special-case the likely()/unlikely() macros for a series of
early gcc 4.x compilers which used to produce very bad code when using
__builtin_expect(x,1), which basically used to build an integer (0 or 1)
from a condition then compare it to integer 1. This was already fixed in
5.x, but even now, looking at the code produced by various flavors of 4.x
this bad behavior couldn't be witnessed anymore. So let's consider it as
fixed by now, which will allow to get rid of some ugly tricks at some
specific places. A test on 4.7.4 shows that the code shrinks by about 3kB
now, thanks to some tests being inlined closer to the call place and the
unlikely case being moved to real functions. See the link below for more
background on this.
Link: https://www.mail-archive.com/haproxy@formilux.org/msg36392.html
These ones are irrelevant to the config but rather to the platform, and
as such are better placed in compiler.h.
Here we take the opportunity for declaring a few extra capabilities:
- HA_UNALIGNED : CPU supports unaligned accesses
- HA_UNALIGNED_LE : CPU supports unaligned accesses in little endian
- HA_UNALIGNED_FAST : CPU supports fast unaligned accesses
- HA_UNALIGNED_ATOMIC : CPU supports unaligned accesses in atomics
This will help remove a number of #ifdefs with arch-specific statements.
Add a function that finds a character in an ist and returns an
updated ist with the length of the portion of the original string
that doesn't contain the char.
Might be backported to 2.1
The function is_idchar() was added by commit 36f586b ("MINOR: tools:
add is_idchar() to tell if a char may belong to an identifier") to
ease matching of sample fetch/converter names. But it lacked support
for the '+' character used in "base32+src" and "url32+src". A quick
way to figure the list of supported sample fetch+converter names is
to issue the following command:
git grep '"[^"]*",.*SMP_T_.*SMP_USE_'|cut -f2 -d'"'|sort -u
No more entry is reported once searching for characters not covered
by is_idchar().
No backport is needed.
This does like chunk_strcpy() except that the maximum string length may
be limited by the caller. A trailing zero is always appended. This is
particularly handy to extract portions of strings to put into the trash
for use with libc functions requiring a nul-terminated string.
While looking for other occurrences of do { continue; } while (0) I
found these few leftovers in mini-clist where an outer loop was made
around "do { } while (0)" then another loop was placed inside just to
handle the continue. Let's clean this up by just removing the outer
one. Most of the patch is only the inner part of the loop that is
reindented. It was verified that the resulting code is the same.
the htx_append_msg() function can now be used to append an HTX message to
another one. All the message is copied or nothing. If an error occurs during the
copy, all changes are rolled back.
This patch is mandatory to fix a bug in http_reply_and_close() function. Be
careful to backport it first.
In __pool_get_first(), don't forget to unlock the pool lock if the pool is
empty, otherwise no writer will be able to take the lock, and as it is done
when reloading, it leads to an infinite loop on reload.
This should be backported with commit 04f5fe87d3
When using lockless pools, add a new rwlock, flush_pool. read-lock it when
getting memory from the pool, so that concurrenct access are still
authorized, but write-lock it when we're about to free memory, in
pool_flush() and pool_gc().
The problem is, when removing an item from the pool, we unreference it
to get the next one, however, that pointer may have been free'd in the
meanwhile, and that could provoke a crash if the pointer has been unmapped.
It should be OK to use a rwlock, as normal operations will still be able
to access the pool concurrently, and calls to pool_flush() and pool_gc()
should be pretty rare.
This should be backported to 2.1, 2.0 and 1.9.
"set ssl cert <filename> <payload>" CLI command should have the same
result as reload HAproxy with the updated pem file (<filename>).
Is not the case, DHparams/cert-chain is kept from the previous
context if no DHparams/cert-chain is set in the context (<payload>).
This patch should be backport to 2.1
For complex stick tables with many entries/columns, it can be beneficial
to filter using multiple criteria. The maximum number of filter entries
can be controlled by defining STKTABLE_FILTER_LEN during build time.
This patch can be backported to older releases.
while working on issue #429, I encountered build failures with various
non-released openssl versions, let us improve ssl defines, switch to
features, not versions, for EVP_CTRL_AEAD_SET_IVLEN and
EVP_CTRL_AEAD_SET_TAG.
No backport is needed as there is no valid reason to build a stable haproxy
version against a development version of openssl.
Wietse Venema reported in the thread below that we have a signedness
issue with our hashes implementations: due to the use of const char*
for the input key that's often text, the crc32, sdbm, djb2, and wt6
algorithms return a platform-dependent value for binary input keys
containing bytes with bit 7 set. This means that an ARM or PPC
platform will hash binary inputs differently from an x86 typically.
Worse, some algorithms are well defined in the industry (like CRC32)
and do not provide the expected result on x86, possibly causing
interoperability issues (e.g. a user-agent would fail to compare the
CRC32 of a message body against the one computed by haproxy).
Fortunately, and contrary to the first impression, the CRC32c variant
used in the PROXY protocol processing is not affected. Thus the impact
remains very limited (the vast majority of input keys are text-based,
such as user-agent headers for exmaple).
This patch addresses the issue by fixing all hash functions' prototypes
(even those not affected, for API consistency). A reg test will follow
in another patch.
The vast majority of users do not use these hashes. And among those
using them, very few will pass them on binary inputs. However, for the
rare ones doing it, this fix MAY have an impact during the upgrade. For
example if the package is upgraded on one LB then on another one, and
the CRC32 of a binary input is used as a stick table key (why?) then
these CRCs will not match between both nodes. Similarly, if
"hash-type ... crc32" is used, LB inconsistency may appear during the
transition. For this reason it is preferable to apply the patch on all
nodes using such hashes at the same time. Systems upgraded via their
distros will likely observe the least impact since they're expected to
be upgraded within a short time frame.
And it is important for distros NOT to skip this fix, in order to avoid
distributing an incompatible implementation of a hash. This is the
reason why this patch is tagged as MAJOR, eventhough it's extremely
unlikely that anyone will ever notice a change at all.
This patch must be backported to all supported branches since the
hashes were introduced in 1.5-dev20 (commit 98634f0c). Some parts
may be dropped since implemented later.
Link to Wietse's report:
https://marc.info/?l=postfix-users&m=157879464518535&w=2
SSL_CTX_set_ecdh_auto() is not defined when OpenSSL 1.1.1 is compiled
with the no-deprecated option. Remove existing, incomplete guards and
add a compatibility macro in openssl-compat.h, just as OpenSSL does:
bf4006a6f9/include/openssl/ssl.h (L1486)
This should be backported as far as 2.0 and probably even 1.9.
LIBRESSL_VERSION_NUMBER evaluates to 0 under OpenSSL, making the condition
always true. Check for the define before checking it.
Signed-off-by: Rosen Penev <rosenp@gmail.com>
[wt: to be backported as far as 1.9]
Typically server line like:
'server-template srv 1-1000 *:443 ssl ca-file ca-certificates.crt'
load ca-certificates.crt 1000 times and stay duplicated in memory.
Same case for bind line: ca-file is loaded for each certificate.
Same 'ca-file' can be load one time only and stay deduplicated in
memory.
As a corollary, this will prevent file access for ca-file when
updating a certificate via CLI.
This new function looks for the first control character in a string (a
char whose value is between 0x00 and 0x1F included) and returns it, or
NULL if there is none. It is optimized for quickly evicting non-matching
strings and scans ~0.43 bytes per cycle. It can be used as an accelerator
when it's needed to look up several of these characters (e.g. CR/LF/NUL).
The link to the known bugs page for the current version is built and
reported there. When it is a development version (less than 2 dots),
instead a link to github open issues is reported as there's no way to
be sure about the current situation in this case and it's better that
users report their trouble there.
As discussed on Discourse here:
https://discourse.haproxy.org/t/haproxy-branch-support-lifetime/4466
it's not always easy for end users to know the lifecycle of the version
they are using. This patch introduces a "Status" line in the output of
"haproxy -vv" indicating whether it's a development, stable, long-term
supported version, possibly with an estimated end of life for the branch
when it can be anticipated (e.g. for stable versions). This field should
be adjusted when creating a major release to reflect the new status.
It may make sense to backport this to other branches to clarify the
situation.
This reverts commit 9e46496d45. It was
wrong and is not reliable, depending on the compiler's version and
optimization, as the struct is assigned inside a statement, thus on
its own stack. It's not needed anymore now so let's remove this.
We previously relied on chunk_cat(dst, b_fromist(src)) for this but it
is not reliable as the allocated buffer is inside the expression and
may be on a temporary stack. While it's possible to allocate stack space
for a struct and return a pointer to it, it's not possible to initialize
it form a temporary variable to prevent arguments from being evaluated
multiple times. Since this is only used to append an ist after a chunk,
let's instead have a chunk_istcat() function to perform exactly this
from a native ist.
The only call place (URI computation in the cache) was updated.
Debug commands will usually mark the fate of the process. We'd rather
have them counted and visible in a core or in stats output than trying
to guess how a flag combination could happen. The counter is only
incremented when the command is about to be issued however, so that
failed attempts are ignored.
8c1cddef ("MINOR: ssl: new functions duplicate and free a ckch_store")
use some OpenSSL refcount functions that were introduced in OpenSSL
1.0.2 and OpenSSL 1.1.0.
Fix the problem by introducing them in openssl-compat.h.
Fix#336.
As reported in issue #335, a lot of contention happens on the PATLRU lock
when performing expensive regex lookups. This is absurd since the purpose
of the LRU cache was to have a fast cache for expressions, thus the cache
must not be shared between threads and must remain lockless.
This commit makes the LRU cache thread-local and gets rid of the PATLRU
lock. A test with 7 threads on 4 cores climbed from 67kH/s to 369kH/s,
or a scalability factor of 5.5.
Given the huge performance difference and the regression caused to
users migrating from processes to threads, this should be backported at
least to 2.0.
Thanks to Brian Diekelman for his detailed report about this regression.
In MT_LIST_BEHEAD(), explicitely set the next element of the prev to NULL,
instead of setting it to the prev of the next. If we only had one element,
then we'd set the next and the prev to the element itself, and thus it would
make the element appear to be outside any list.
A lot of our chunk-based functions are able to work on a buffer pointer
but not on an ist. Instead of duplicating all of them to also take an
ist as a source, let's have a macro to make a temporary dummy buffer
from an ist. This will only result in structure field manipulations
that the compiler will quickly figure to eliminate them with inline
functions, and in other cases it will just use 4 words in the stack
before calling a function, instead of performing intermediary
conversions.
The flag HTX_FL_PROXY_RESP is now set on responses generated by HAProxy,
excluding responses returned by applets and services. It is an informative flag
set by the applicative layer.
It currently is not possible to figure the exact haproxy version from a
core file for the sole reason that the version is stored into a const
string and as such ends up in the .text section that is not part of a
core file. By turning them into variables we move them to the data
section and they appear in core files. In order to help finding them,
we just prepend an extra variable in front of them and we're able to
immediately spot the version strings from a core file:
$ strings core | fgrep -A2 'HAProxy version'
HAProxy version follows
2.1-dev2-e0f48a-88
2019/10/15
(These are haproxy_version and haproxy_date respectively). This may be
backported to 2.0 since this part is not support to impact anything but
the developer's time spent debugging.
When raw data are copied or appended in a chunk, the result must not exceed the
chunk size but it can reach it. Unlike functions to copy or append a string,
there is no terminating null byte.
This patch must be backported as far as 1.8. Note in 1.8, the functions
chunk_cpy() and chunk_cat() don't exist.
$ echo -e "set ssl cert certificate.pem <<\n$(cat certificate2.pem)\n" | \
socat stdio /var/run/haproxy.stat
Certificate updated!
The operation is locked at the ckch level with a HA_SPINLOCK_T which
prevents the ckch architecture (ckch_store, ckch_inst..) to be modified
at the same time. So you can't do a certificate update at the same time
from multiple CLI connections.
SNI trees are also locked with a HA_RWLOCK_T so reading operations are
locked only during a certificate update.
Bundles are supported but you need to update each file (.rsa|ecdsa|.dsa)
independently. If a file is used in the configuration as a bundle AND
as a unique certificate, both will be updated.
Bundles, directories and crt-list are supported, however filters in
crt-list are currently unsupported.
The code tries to allocate every SNIs and certificate instances first,
so it can rollback the operation if that was unsuccessful.
If you have too much instances of the certificate (at least 20000 in my
tests on my laptop), the function can take too much time and be killed
by the watchdog. This will be fixed later. Also with too much
certificates it's possible that socat exits before the end of the
generation without displaying a message, consider changing the socat
timeout in this case (-t2 for example).
The size of the certificate is currently limited by the maximum size of
a payload, that must fit in a buffer.
This macro atomically cuts the head of a list and returns the list
of elements as a detached list, meaning that they're all linked
together without any head. If the list was empty, NULL is returned.
We used to rely on some config flags defined in uri_auth.h set during
parsing, and another set of STAT_* flags defined in stats.h set at run
time, with a somewhat gray area between the two sets. This is confusing
in the stats code as both are called "flags" in various functions and
it's quite hard to know which one describes what.
This patch cleans this up by replacing all ST_* by a newly assigned
value from the STAT_* set so that we can now use unified flags to
describe both the configuration and the current state. There is no
functional change at all.
This flag was added in 1.4-rc1 by commit 329f74d463 ("[BUG] uri_auth: do
not attemp to convert uri_auth -> http-request more than once") to
address the case where two proxies inherit the stats settings from
the defaults instance, and the first one compiles the expression while
the second one uses it. In this case since they use the exact same
uri_auth pointer, only the first one should compile and the second one
must not fail the check. This was addressed by adding an ST_CONVDONE
flag indicating that the expression conversion was completed and didn't
need to be done again. But this is a hack and it becomes cumbersome in
the middle of the other flags which are all relevant to the stats
applet. Let's instead fix it by checking if we're dealing with an
alias of the defaults instance and refrain from compiling this twice.
This allows us to remove the ST_CONVDONE flag.
A typical config requiring this check is :
defaults
mode http
stats auth foo:bar
listen l1
bind :8080
listen l2
bind :8181
Without this (or previous) check it would cmoplain when checking l2's
validity since the rule was already built.
The function http_get_authority() may be used to parse a URI and looks for the
authority, between the scheme and the path. An option may be used to skip the
user info (part before the '@'). Most of time, the user info will be ignored.
The first flag, HTX_SL_F_HAS_AUTHORITY, is set when the uri contains an
authority. For the H1, it happens when a CONNECT request is received or when an
absolute uri is used. For the H2, it happens when the pseudo header ":authority"
is provided.
The second one, HTX_SL_F_NORMALIZED_URI, is set when the received uri is
represented as an absolute uri because of the protocol requirements. For now, it
is only used for h2 requests, when the pseudo headers :authority and :scheme are
found. Internally, the uri is represented as an absolute uri. This flag allows
us to make the difference between an absolute uri in h1 and h2.
This function now dumps info about the HTX message into a buffer, passed as
argument. In addition, it is possible to only dump meta information, without the
message content.
We often need ISO time + microseconds in traces and ring buffers, thus
function does this by calling gettimeofday() and keeping a cached value
of the part representing the tv_sec value, and only rewrites the microsecond
part. The cache is per-thread so it's lockless and safe to use as-is.
Some tests already show that it's easy to see 3-4 events in a single
microsecond, thus it's likely that the nanosecond version will have to
be implemented as well. But certain comments on the net suggest that
some parsers are having trouble beyond microsecond, thus for now let's
stick to the microsecond only.
Make it so MT_LIST_ADD and MT_LIST_ADDQ return 1 if it managed to add the
item, 0 (because it was already in a list) otherwise.
Make it so MT_LIST_DEL returns 1 if it managed to remove the item from a
list, or 0 otherwise (because it was in no list).
Add a few new macroes to the mt_lists.
MT_LIST_LOCK_ELT()/MT_LIST_UNLOCK_ELT() helps locking/unlocking an element.
This should only be used if you know for sure nobody else will remove the
element from the list in the meanwhile.
mt_list_for_each_entry_safe() is an iterator, similar to
list_for_each_entry_safe().
It takes 5 arguments, item, list_head, member are similar to those of
the non-mt variant, tmpelt is a temporary pointer to a struct mt_list, while
tmpelt2 is a struct mt_list itself.
MT_LIST_DEL_SELF() can be used to delete an item while parsing the list with
mt_list_for_each_entry_safe(). It shouldn't be used outside, and you
shouldn't use MT_LIST_DEL() while using mt_list_for_each_entry_safe().
Instead of using the same type for regular linked lists and "autolocked"
linked lists, use a separate type, "struct mt_list", for the autolocked one,
and introduce a set of macros, similar to the LIST_* macros, with the
MT_ prefix.
When we use the same entry for both regular list and autolocked list, as
is done for the "list" field in struct connection, we know have to explicitely
cast it to struct mt_list when using MT_ macros.
To avoid code duplication in the futur mux FCGI, functions parsing H1 messages
and converting them into HTX have been moved in the file h1_htx.c. Some
specific parts remain in the mux H1. But most of the parsing is now generic.
This new flag may be used to report unexpected error because of not well
formatted HTX messages (not related to a parsing error) or our incapactity to
handle the processing because we reach a limit (ressource exhaustion, too big
headers...). It should result to an error 500 returned to the client when
applicable.
In prompts on the CLI we now commonly need to propose a keyword name
and a description and it doesn't make sense to define a new struct for
each such pairs. Let's simply have a generic "name_desc" for this.
The new functions are :
__b_put_varint() : inserts a varint when it's known that it fits
b_put_varint() : tries to insert a varint at the tail
b_get_varint() : tries to get a varint from the head
b_peek_varint() : tries to peek a varint at a specific offset
Wrapping is supported so that they are expected to be safe to use to
manipulate varints with buffers anywhere.
It will sometimes be useful to encode varints to know the output size in
advance. Two versions are provided, one inline using a switch/case construct
which will be trivial for use with constants (and will be very fast albeit
huge) and one function iterating on the number which is 5 times smaller,
for use with variables.
The function call tracing code is a quite old and was never ported to
support threads. It's not even sure whether it still works well, but
at least its presence creates confusion for future work so let's rename
it to calltrace.c and add a comment about its lack of thread-safety.
It's sometimes convenient for debugging macros not to be forced to
explicitly pass NULL in an unused argument. This macro does this, it
replaces a missing arg with NULL.
This is somewhat related to indent_msg() except that this one places a
known prefix at the beginning of each line, allows to replace the EOL
character, and not to insert a prefix on the first line if not desired.
It works with a normal output buffer/chunk so it doesn't need to allocate
anything nor to modify the input string. It is suitable for use in multi-
line backtraces.
Since last commit there's no point anymore in having two variants of the
same function, let's switch to b_free() only. __b_drop() was renamed to
__b_free() for obvious consistency reasons.
A small race exists in buffers with "show sess all". This one wants to show
some information grabbed from the buffer (especially in HTX mode). But the
thread owning this buffer might just be releasing its area, right after a
free() or munmap() call, resulting in a head that is not seen as empty yet
though the area was released. It may then be dereferenced by "show sess all"
causing a crash. Note that in practice it only happens in debug mode with
UAF enabled, but it's tricky enough to fix it right now.
This should be backported to stable versions which support threads and a
store barrier. It's worth noting that by performing the clearing first,
b_free() and b_drop() now become two exact equivalent.
Commit 85b2cae63 ("MINOR: pools: make the thread harmless during the
mmap/munmap syscalls") was used to relax the pressure experienced by
other threads when running in debug mode with UAF enabled. It places
a pair of thread_harmless_now()/thread_harmless_end() around the call
to mmap(), assuming callers are not sensitive to parallel activity.
But there are a few cases like "show sess all" where this happens in
isolated threads, and marking the thread as harmless there is a very
bad idea, even worse when arriving to thread_harmless_end() which loops
forever.
Let's only do that when the thread is not isolated. No backport is
needed as the patch above was only in 2.1-dev.
It happens that upon looping threads the watchdog fires, starts a dump,
and other threads expire their budget while waiting for the other threads
to get dumped and trigger a watchdog event again, adding some confusion
to the traces. With this patch the situation becomes clearer as we export
the list of threads being dumped so that the watchdog can check it before
deciding to trigger. This way such threads in queue for being dumped are
not attempted to be reported in turn.
This should be backported to 2.0 as it helps understand stack traces.
This one was added by commit daacf3664 ("BUG/MEDIUM: protocols: add a
global lock for the init/deinit stuff") but I forgot to add it to the
include file, breaking DEBUG_THREAD.
Default HTTP error messages are stored in an array of chunks. And since the HTX
was added, these messages are also converted in HTX and stored in another
array. But now, the first array is not used anymore because the legacy HTTP mode
was removed.
So now, only the array with the HTX messages are kept. The other one was
removed.
Because the h2 multiplexer only uses the HTX mode, following H2 functions were
removed :
* h2_prepare_h1_reqline
* h2_make_h1_request()
* h2_make_h1_trailers()
Instead of using a array of (struct block), it is more natural and intuitive to
use an array of char. Indeed, not only (struct block) are stored in this array,
but also their payload.
<head> and <tail> fields are now signed 32-bits integers. For an empty HTX
message, these fields are set to -1. So the field <used> is now useless and can
safely be removed. To know if an HTX message is empty or not, we just compare
<head> against -1 (it also works with <tail>). The function htx_nbblks() has
been added to get the number of used blocks.
These calls can take quite some time and leave the thread harmless so
it's better to mark it as such. This makes "show sess" respond way
faster during high loads running on processes build with DEBUG_UAF
since these calls are stressed a lot.