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Segmentation fault in NDPluginPvxs when an NDArray has string attributes #613
Description
Steps to reproduce:
- Configure the PVXS plugin in commonPlugins.cmd
- Run the simDetectorIOC from ADSimDetector
- Use simDetectorAttributes.xml as the detector attributes file
- Enable NDPluginPvxs callbacks and start acquisition
- IOC crashes at the first frame
Backtrace:
Thread 223 "PVA1_Plugin_1" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fff68d486c0 (LWP 949501)]
__strlen_avx2 () at ../sysdeps/x86_64/multiarch/strlen-avx2.S:76
warning: 76 ../sysdeps/x86_64/multiarch/strlen-avx2.S: No such file or directory
(gdb) bt
#0 __strlen_avx2 () at ../sysdeps/x86_64/multiarch/strlen-avx2.S:76
#1 0x00007ffff7d7d169 in std::char_traits<char>::length
(__s=0x6973206369736142 <error: Cannot access memory at address 0x6973206369736142>)
at /usr/include/c++/13/bits/char_traits.h:399
#2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::basic_string
(__a=<optimized out>, __s=0x6973206369736142 <error: Cannot access memory at address 0x6973206369736142>, this=0x7fff68d47070) at /usr/include/c++/13/bits/basic_string.h:648
#3 NTNDArrayConverterPvxs::fromStringAttribute (this=this@entry=0x555555703b40, destValue=..., src=src@entry=0x7ffe9c4f6650)
at ../ntndArrayConverterPvxs.cpp:448
#4 0x00007ffff7d7e1b1 in NTNDArrayConverterPvxs::fromAttributes (this=0x555555703b40, src=<optimized out>)
at ../ntndArrayConverterPvxs.cpp:500
#5 0x00007ffff7d82696 in NTNDArrayConverterPvxs::fromArray (this=0x555555703b40, src=src@entry=0x7ffe9c401560)
at ../ntndArrayConverterPvxs.cpp:206
#6 0x00007ffff7f5dd41 in NTNDArrayRecordPvxs::update (this=0x55555583a3c0, pArray=pArray@entry=0x7ffe9c401560)
at ../NDPluginPvxs.cpp:63
#7 0x00007ffff7f5de13 in NDPluginPvxs::processCallbacks (this=0x555556543100, pArray=0x7ffe9c401560)
at /usr/include/c++/13/bits/shared_ptr_base.h:1665
#8 0x00007ffff7eb4b24 in NDPluginDriver::processTask (this=0x555556543100) at ../NDPluginDriver.cpp:534
#9 0x00007ffff7aa723d in epicsThreadCallEntryPoint (pPvt=0x555556508410) at ../osi/epicsThread.cpp:94
#10 0x00007ffff7aabdad in start_routine (arg=0x55555650b3a0) at ../osi/os/posix/osdThread.c:444
#11 0x00007ffff789cb84 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:447
#12 0x00007ffff7929ecc in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78
Activity
pgap commentedon Oct 28, 2026
With the patch from #614 the crash does not happen and string attributes seem to be converted correctly