In short the easy handle needs to be disconnected from its connection at
this point since the connection still is serving other easy handles.
In our app we can reliably reproduce a crash in our http2 stress test
that is fixed by this change. I can't easily reproduce the same test in
a small example.
This is the gdb/asan output:
==11785==ERROR: AddressSanitizer: heap-use-after-free on address 0xe9f4fb80 at pc 0x09f41f19 bp 0xf27be688 sp 0xf27be67c
READ of size 4 at 0xe9f4fb80 thread T13 (RESOURCE_HTTP)
#0 0x9f41f18 in curl_multi_remove_handle /path/to/source/3rdparty/curl/lib/multi.c:666
0xe9f4fb80 is located 0 bytes inside of 1128-byte region [0xe9f4fb80,0xe9f4ffe8)
freed by thread T13 (RESOURCE_HTTP) here:
#0 0xf7b1b5c2 in __interceptor_free /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_malloc_linux.cc:45
#1 0x9f7862d in conn_free /path/to/source/3rdparty/curl/lib/url.c:2808
#2 0x9f78c6a in Curl_disconnect /path/to/source/3rdparty/curl/lib/url.c:2876
#3 0x9f41b09 in multi_done /path/to/source/3rdparty/curl/lib/multi.c:615
#4 0x9f48017 in multi_runsingle /path/to/source/3rdparty/curl/lib/multi.c:1896
#5 0x9f490f1 in curl_multi_perform /path/to/source/3rdparty/curl/lib/multi.c:2123
#6 0x9c4443c in perform /path/to/source/src/net/resourcemanager/ResourceManagerCurlThread.cpp:854
#7 0x9c445e0 in ...
#8 0x9c4cf1d in ...
#9 0xa2be6b5 in ...
#10 0xf7aa5780 in asan_thread_start /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_interceptors.cc:226
#11 0xf4d3a16d in __clone (/lib/i386-linux-gnu/libc.so.6+0xe716d)
previously allocated by thread T13 (RESOURCE_HTTP) here:
#0 0xf7b1ba27 in __interceptor_calloc /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_malloc_linux.cc:70
#1 0x9f7dfa6 in allocate_conn /path/to/source/3rdparty/curl/lib/url.c:3904
#2 0x9f88ca0 in create_conn /path/to/source/3rdparty/curl/lib/url.c:5797
#3 0x9f8c928 in Curl_connect /path/to/source/3rdparty/curl/lib/url.c:6438
#4 0x9f45a8c in multi_runsingle /path/to/source/3rdparty/curl/lib/multi.c:1411
#5 0x9f490f1 in curl_multi_perform /path/to/source/3rdparty/curl/lib/multi.c:2123
#6 0x9c4443c in perform /path/to/source/src/net/resourcemanager/ResourceManagerCurlThread.cpp:854
#7 0x9c445e0 in ...
#8 0x9c4cf1d in ...
#9 0xa2be6b5 in ...
#10 0xf7aa5780 in asan_thread_start /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_interceptors.cc:226
#11 0xf4d3a16d in __clone (/lib/i386-linux-gnu/libc.so.6+0xe716d)
SUMMARY: AddressSanitizer: heap-use-after-free /path/to/source/3rdparty/curl/lib/multi.c:666 in curl_multi_remove_handle
Shadow bytes around the buggy address:
0x3d3e9f20: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x3d3e9f30: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x3d3e9f40: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x3d3e9f50: fd fd fd fd fd fd fd fd fd fd fd fd fd fa fa fa
0x3d3e9f60: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x3d3e9f70:[fd]fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x3d3e9f80: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x3d3e9f90: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x3d3e9fa0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x3d3e9fb0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x3d3e9fc0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
Shadow byte legend (one shadow byte represents 8 application bytes):
Addressable: 00
Partially addressable: 01 02 03 04 05 06 07
Heap left redzone: fa
Heap right redzone: fb
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack partial redzone: f4
Stack after return: f5
Stack use after scope: f8
Global redzone: f9
Global init order: f6
Poisoned by user: f7
Container overflow: fc
Array cookie: ac
Intra object redzone: bb
ASan internal: fe
Left alloca redzone: ca
Right alloca redzone: cb
==11785==ABORTING
Thread 14 "RESOURCE_HTTP" received signal SIGABRT, Aborted.
[Switching to Thread 0xf27bfb40 (LWP 12324)]
0xf7fd8be9 in __kernel_vsyscall ()
(gdb) bt
#0 0xf7fd8be9 in __kernel_vsyscall ()
#1 0xf4c7ee89 in __GI_raise (sig=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#2 0xf4c803e7 in __GI_abort () at abort.c:89
#3 0xf7b2ef2e in __sanitizer::Abort () at /opt/toolchain/src/gcc-6.2.0/libsanitizer/sanitizer_common/sanitizer_posix_libcdep.cc:122
#4 0xf7b262fa in __sanitizer::Die () at /opt/toolchain/src/gcc-6.2.0/libsanitizer/sanitizer_common/sanitizer_common.cc:145
#5 0xf7b21ab3 in __asan::ScopedInErrorReport::~ScopedInErrorReport (this=0xf27be171, __in_chrg=<optimized out>) at /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_report.cc:689
#6 0xf7b214a5 in __asan::ReportGenericError (pc=166993689, bp=4068206216, sp=4068206204, addr=3925146496, is_write=false, access_size=4, exp=0, fatal=true) at /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_report.cc:1074
#7 0xf7b21fce in __asan::__asan_report_load4 (addr=3925146496) at /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_rtl.cc:129
#8 0x09f41f19 in curl_multi_remove_handle (multi=0xf3406080, data=0xde582400) at /path/to/source3rdparty/curl/lib/multi.c:666
#9 0x09f6b277 in Curl_close (data=0xde582400) at /path/to/source3rdparty/curl/lib/url.c:415
#10 0x09f3354e in curl_easy_cleanup (data=0xde582400) at /path/to/source3rdparty/curl/lib/easy.c:860
#11 0x09c6de3f in ...
#12 0x09c378c5 in ...
#13 0x09c48133 in ...
#14 0x09c4d092 in ...
#15 0x0a2be6b6 in ...
#16 0xf7aa5781 in asan_thread_start (arg=0xf2d22938) at /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_interceptors.cc:226
#17 0xf5de52b5 in start_thread (arg=0xf27bfb40) at pthread_create.c:333
#18 0xf4d3a16e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:114
Fixes#1083
The closure handle only ever has default timeouts set. To improve the
state somewhat we clone the timeouts from each added handle so that the
closure handle always has the same timeouts as the most recently added
easy handle.
Fixes#739
Speed limits (from CURLOPT_MAX_RECV_SPEED_LARGE &
CURLOPT_MAX_SEND_SPEED_LARGE) were applied simply by comparing limits
with the cumulative average speed of the entire transfer; While this
might work at times with good/constant connections, in other cases it
can result to the limits simply being "ignored" for more than "short
bursts" (as told in man page).
Consider a download that goes on much slower than the limit for some
time (because bandwidth is used elsewhere, server is slow, whatever the
reason), then once things get better, curl would simply ignore the limit
up until the average speed (since the beginning of the transfer) reached
the limit. This could prove the limit useless to effectively avoid
using the entire bandwidth (at least for quite some time).
So instead, we now use a "moving starting point" as reference, and every
time at least as much as the limit as been transferred, we can reset
this starting point to the current position. This gets a good limiting
effect that applies to the "current speed" with instant reactivity (in
case of sudden speed burst).
Closes#971
With HTTP/2 each transfer is made in an indivial logical stream over the
connection, making most previous errors that caused the connection to get
forced-closed now instead just kill the stream and not the connection.
Fixes#941
Previously, passing a timeout of zero to Curl_expire() was a magic code
for clearing all timeouts for the handle. That is now instead made with
the new Curl_expire_clear() function and thus a 0 timeout is fine to set
and will trigger a timeout ASAP.
This will help removing short delays, in particular notable when doing
HTTP/2.
Regression added in 790d6de485. The was then added to avoid one
particular transfer to starve out others. But when aborting due to
reading the maxcount, the connection must be marked to be read from
again without first doing a select as for some protocols (like SFTP/SCP)
the data may already have been read off the socket.
Reported-by: Dan Donahue
Bug: https://curl.haxx.se/mail/lib-2016-07/0057.html
The proper FTP wildcard init is now more properly done in Curl_pretransfer()
and the corresponding cleanup in Curl_close().
The previous place of init/cleanup code made the internal pointer to be NULL
when this feature was used with the multi_socket() API, as it was made within
the curl_multi_perform() function.
Reported-by: Jonathan Cardoso Machado
Fixes#800
curl_printf.h defines printf to curl_mprintf, etc. This can cause
problems with external headers which may use
__attribute__((format(printf, ...))) markers etc.
To avoid that they cause problems with system includes, we include
curl_printf.h after any system headers. That makes the three last
headers to always be, and we keep them in this order:
curl_printf.h
curl_memory.h
memdebug.h
None of them include system headers, they all do funny #defines.
Reported-by: David Benjamin
Fixes#743
Previously, when a stream was closed with other than NGHTTP2_NO_ERROR
by RST_STREAM, underlying TCP connection was dropped. This is
undesirable since there may be other streams multiplexed and they are
very much fine. This change introduce new error code
CURLE_HTTP2_STREAM, which indicates stream error that only affects the
relevant stream, and connection should be kept open. The existing
CURLE_HTTP2 means connection error in general.
Ref: https://github.com/curl/curl/issues/659
Ref: https://github.com/curl/curl/pull/663
Simplify the code by using a single entry that looks for a socket in the
socket hash. As indicated in #712, the code looked for CURL_SOCKET_BAD
at some point and that is ineffective/wrong and this makes it easier to
avoid that.
Such a return value isn't documented but could still happen, and the
curl tool code checks for it. It would happen when the underlying
Curl_poll() function returns an error. Starting now we mask that error
as a user of curl_multi_wait() would have no way to handle it anyway.
Reported-by: Jay Satiro
Closes#707
The internal Curl_done() function uses Curl_expire() at times and that
uses the timeout list. Better clean up the list once we're done using
it. This caused a segfault.
Reported-by: 蔡文凱
Bug: https://curl.haxx.se/mail/lib-2016-02/0097.html
introduced in c6aedf680f. It needs to be CURLM_STATE_LAST big since it
must hande the range 0 .. CURLM_STATE_MSGSENT (18) and CURLM_STATE_LAST
is 19 right now.
Reported-by: Dan Fandrich
Bug: http://curl.haxx.se/mail/lib-2015-10/0069.html
... and assign it from the set.fread_func_set pointer in the
Curl_init_CONNECT function. This A) avoids that we have code that
assigns fields in the 'set' struct (which we always knew was bad) and
more importantly B) it makes it impossibly to accidentally leave the
wrong value for when the handle is re-used etc.
Introducing a state-init functionality in multi.c, so that we can set a
specific function to get called when we enter a state. The
Curl_init_CONNECT is thus called when switching to the CONNECT state.
Bug: https://github.com/bagder/curl/issues/346Closes#346
With many easy handles using the same connection for multiplexing, it is
important we store and keep the transfer-oriented stuff in the
SessionHandle so that callbacks and callback data work fine even when
many easy handles share the same physical connection.
.. also make __func__ replacement in multi.
Prior to this change debug builds would fail to build if the compiler
was building pre-c99 and didn't support __func__.
to allow code to act differently on the situation.
Also added some more info message for the connection re-use function to
make it clearer when connections are not re-used.
All the existing Curl_bundle* functions were only ever used from within
the conncache.c file, so I moved them over and made them static (and
removed the Curl_ prefix).
This avoids unnecessary dynamic allocs and as this also removed the last
users of *hash_alloc() and *hash_destroy(), those two functions are now
removed.
Anders Bakken