Java crashes using musl-1.2.5

[David Holmes]

Hi,

At present we don't really expect statx to work on Musl-C IIUC the code 
correctly, but Musl-C 1.2.5 has added it:

 > This release adds extension functions statx

so likely our code needs adjusting to match what is now provided.

David

On 10/09/2025 10:54 pm, Konstantin Kletschke wrote:
> Hello,
> 
> I am used to crosscompile openjdk for cortex-a[7|8|9] manually or using
> buildroot framework without severe Problems.
> ARM EABIhf 32Bit.
> 
> However recently I got in contact with a customer's rootfs using
> musl-1.2.5 instead of musl-1.2.4 which I was used to and had no problems with.
> 
> Severe debugging resulted in the crash whenever musl-1.2.5 was used in
> the target (regardeless what musl version was used to crosscompile and
> regardeless with java I tried, correto-24, openjdk-21, openjdk-24).
> 
> I tested with a helloworld downloaded from github somewhere.
> "java -jar helloworld.jar" crashes. Unzippping the jar and using
> "java -cp . HelloWorld" works!
> 
> Crashes looks something like those:
> 
> #  SIGSEGV (0xb) at pc=0x7693e018, pid=8026, tid=8027
> #
> # JRE version: OpenJDK Runtime Environment (21.0+21) (build 21+21)
> # Java VM: OpenJDK Server VM (21+21, mixed mode, serial gc, linux-arm)
> # Problematic frame:
> # V  [libjvm.so+0x61e018]
> 
> FATAL ERROR in native method: Null object passed to JNI
>    at sun.nio.fs.UnixNativeDispatcher.stat0(java.base at 21/Native Method)
>    at sun.nio.fs.UnixNativeDispatcher.stat(java.base at 21/Unknown Source)
>    at sun.nio.fs.UnixFileAttributes.get(java.base at 21/Unknown Source)
>    at sun.nio.fs.UnixFileAttributeViews$Basic.readAttributes(java.base at 21/Unknown Source)
>    at sun.nio.fs.UnixFileSystemProvider.readAttributes(java.base at 21/Unknown Source)
>    at sun.nio.fs.LinuxFileSystemProvider.readAttributes(java.base at 21/Unknown Source)
>    at java.nio.file.Files.readAttributes(java.base at 21/Unknown Source)
>    at java.util.zip.ZipFile$Source.get(java.base at 21/Unknown Source)
>    at java.util.zip.ZipFile$CleanableResource.<init>(java.base at 21/Unknown Source)
>    at java.util.zip.ZipFile.<init>(java.base at 21/Unknown Source)
>    at java.util.zip.ZipFile.<init>(java.base at 21/Unknown Source)
>    at java.util.jar.JarFile.<init>(java.base at 21/Unknown Source)
>    at java.util.jar.JarFile.<init>(java.base at 21/Unknown Source)
>    at java.util.jar.JarFile.<init>(java.base at 21/Unknown Source)
>    at sun.launcher.LauncherHelper.getMainClassFromJar(java.base at 21/Unknown Source)
>    at sun.launcher.LauncherHelper.loadMainClass(java.base at 21/Unknown Source)
>    at sun.launcher.LauncherHelper.checkAndLoadMain(java.base at 21/Unknown Source)
> Aborted
> 
> 
> With 1.2.4 everything works fine.
> 
> 
> Farther debugging revealed that following fix in Java allowed to run it
> with 1.2.5:
> 
> Index: openjdk-21.0.9+6/src/java.base/unix/native/libnio/fs/UnixNativeDispatcher.c
> ===================================================================
> --- openjdk-21.0.9+6.orig/src/java.base/unix/native/libnio/fs/UnixNativeDispatcher.c
> +++ openjdk-21.0.9+6/src/java.base/unix/native/libnio/fs/UnixNativeDispatcher.c
> @@ -430,7 +430,7 @@ Java_sun_nio_fs_UnixNativeDispatcher_ini
>       capabilities |= sun_nio_fs_UnixNativeDispatcher_SUPPORTS_BIRTHTIME;
> #endif
> #if defined(__linux__)
> -    my_statx_func = (statx_func*) dlsym(RTLD_DEFAULT, "statx");
> +    my_statx_func = NULL;
>       if (my_statx_func != NULL) {
>           capabilities |= sun_nio_fs_UnixNativeDispatcher_SUPPORTS_BIRTHTIME;
>       }
> 
> 
> May be this has something to do with the stat ./. stat64 stuff changed
> in musl from 1.2.4 to 1.2.5 or so.
> I already headed to the musl people but I am not shure if its placed
> better over there or here. I also already showed up at client-libs-dev
> but was told to be come over here.
> 
> Kind Regards
> Konstantin
>