Unable to Copy/Create file on NFS share on macOS

[mikkeljohnsen]

Description

dotnet on macOS is not able to copy files to a NFS share.

The NFS share is working perfectly from "Terminal" and "Finder", files can be created/copied and deleted all works.

But from a dotnet (Net6) application I get "UnauthorizedAccess", when writing. Read is working fine.

Reproduction Steps

Setup NFS share on Linux

/etc/exports

/files	*(fsid=1,crossmnt,rw,insecure,all_squash,async,no_subtree_check,anonuid=99,anongid=99)

Mount on macOS from Finder "nfs://servername/files" will mount on "/Volumes/files"

Terminal and Finder can read and write.

Expected behavior

Should be able to create directory and copy files

Actual behavior

Type: System.UnauthorizedAccessException
Message: Access to the path '/Volumes/files/p10001-20000/p13001-14000/p13101-13200/13156/70487.pdf' is denied.

   at Interop.ThrowExceptionForIoErrno(ErrorInfo errorInfo, String path, Boolean isDirectory, Func`2 errorRewriter)
   at Interop.CheckIo(Error error, String path, Boolean isDirectory, Func`2 errorRewriter)
   at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String path, OpenFlags flags, Int32 mode)
   at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize)
   at System.IO.Strategies.OSFileStreamStrategy..ctor(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize)
   at System.IO.Strategies.FileStreamHelpers.ChooseStrategy(FileStream fileStream, String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, Int64 preallocationSize)
   at System.IO.File.Create(String path)
   at OpenMedicus.IO.Files.CopyFileAsync(DbConnection conn, DbTransaction t, String sourceFile, String description, Int32 patientId, Int32 accountId, Boolean isHidden, IProgress`1 progress, Int32 count, Int32 index, CancellationToken token) in /XMedicus/libxcarefiles/Files.cs:line 180
   at OpenMedicus.IO.Files.CopyFileAsync(String[] files, String description, Int32 patientId, Int32 accountId, Boolean isHidden, IProgress`1 progress, CancellationToken token) in /XMedicus/libxcarefiles/Files.cs:line 109
   at OpenMedicus.IO.FileManager.CopyFileAsync(String[] files, String destpath, Int32 patientId, Int32 accountId, Boolean isHidden, IProgress`1 progress, CancellationToken token) in /XMedicus/libxcarefiles/Manager.cs:line 163
   at OpenMedicus.Journal.Summary.CopyFilesAsync(FileManager fm, List`1 files, Int32 episodeId, String desc, List`1 tags) in /XMedicus/components/summary/Summary.cs:line 800
   at OpenMedicus.Journal.Summary.AttachFilesAsync(List`1 files, String description) in /XMedicus/components/summary/Summary.cs:line 917

Regression?

Not sure if it has been working before. (On Mono it worked).

Known Workarounds

None

Configuration

dotnet version: 6.0.6
macOS: Catalina

Other information

No response

Tagging subscribers to this area: @dotnet/area-system-io
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Issue Details

---

Description

dotnet on macOS is not able to copy files to a NFS share.

The NFS share is working perfectly from "Terminal" and "Finder", files can be created/copied and deleted all works.

But from a dotnet (Net6) application I get "UnauthorizedAccess", when writing. Read is working fine.

Reproduction Steps

Setup NFS share on Linux

/etc/exports

/files	*(fsid=1,crossmnt,rw,insecure,all_squash,async,no_subtree_check,anonuid=99,anongid=99)

Mount on macOS from Finder "nfs://servername/files" will mount on "/Volumes/files"

Terminal and Finder can read and write.

Expected behavior

Should be able to create directory and copy files

Actual behavior

Type: System.UnauthorizedAccessException
Message: Access to the path '/Volumes/files/p10001-20000/p13001-14000/p13101-13200/13156/70487.pdf' is denied.

at Interop.ThrowExceptionForIoErrno(ErrorInfo errorInfo, String path, Boolean isDirectory, Func2 errorRewriter) at Interop.CheckIo(Error error, String path, Boolean isDirectory, Func2 errorRewriter)
at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String path, OpenFlags flags, Int32 mode)
at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize)
at System.IO.Strategies.OSFileStreamStrategy..ctor(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize)
at System.IO.Strategies.FileStreamHelpers.ChooseStrategy(FileStream fileStream, String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, Int64 preallocationSize)
at System.IO.File.Create(String path)
at OpenMedicus.IO.Files.CopyFileAsync(DbConnection conn, DbTransaction t, String sourceFile, String description, Int32 patientId, Int32 accountId, Boolean isHidden, IProgress1 progress, Int32 count, Int32 index, CancellationToken token) in /XMedicus/libxcarefiles/Files.cs:line 180 at OpenMedicus.IO.Files.CopyFileAsync(String[] files, String description, Int32 patientId, Int32 accountId, Boolean isHidden, IProgress1 progress, CancellationToken token) in /XMedicus/libxcarefiles/Files.cs:line 109
at OpenMedicus.IO.FileManager.CopyFileAsync(String[] files, String destpath, Int32 patientId, Int32 accountId, Boolean isHidden, IProgress1 progress, CancellationToken token) in /XMedicus/libxcarefiles/Manager.cs:line 163 at OpenMedicus.Journal.Summary.CopyFilesAsync(FileManager fm, List1 files, Int32 episodeId, String desc, List1 tags) in /XMedicus/components/summary/Summary.cs:line 800 at OpenMedicus.Journal.Summary.AttachFilesAsync(List1 files, String description) in /XMedicus/components/summary/Summary.cs:line 917

Regression?

Not sure if it has been working before. (On Mono it worked).

Known Workarounds

None

Configuration

dotnet version: 6.0.6
macOS: Catalina

Other information

No response

Author:	mikkeljohnsen
Assignees:	-
Labels:	area-System.IO
Milestone:	-

[danmoseley]

Thanks for the report. It would be interesting to compare IO traces to when this is done successfully (eg in the shell). On Linux one would use strace. I don't have access to a Mac but I believe it has something similar called dtrace?

[jozkee]

It works on my macbook using the three ways you mentioned (finder, terminal, and .NET app).

This is my sudo exportfs -v on my Ubuntu NFS server:

/srv/nfs4/home  <world>(rw,wdelay,crossmnt,insecure,root_squash,no_subtree_check,sec=sys,rw,insecure,root_squash,no_all_squash)
/srv/nfs4       <world>(rw,wdelay,crossmnt,root_squash,no_subtree_check,fsid=0,sec=sys,rw,secure,root_squash,no_all_squash)

I also did a chmod 777 /srv/nfs4/home to allow the the client to write to the shared folder.

I'm not sure what might be different on your mac. Perhaps you could share the strace that @danmoseley mentioned (it's called dtruss on macos).

This issue has been marked needs-author-action and may be missing some important information.

[mikkeljohnsen]

...
select(0x39, 0x7FFEECD066D0, 0x7FFEECD06650, 0x7FFEECD065D0, 0x7FFEECD06750)		 = 0 0
select(0x39, 0x7FFEECD066D0, 0x7FFEECD06650, 0x7FFEECD065D0, 0x7FFEECD06750)		 = 0 0
select(0x39, 0x7FFEECD066D0, 0x7FFEECD06650, 0x7FFEECD065D0, 0x7FFEECD06750)		 = 0 0
select(0x39, 0x7FFEECD066D0, 0x7FFEECD06650, 0x7FFEECD065D0, 0x7FFEECD06750)		 = 0 0
workq_kernreturn(0x100, 0x70000E82AB80, 0x1)		 = 0 -2
bsdthread_ctl(0x100, 0x0, 0x21573)		 = 0 ?P???0
bsdthread_ctl(0x100, 0x0, 0x0)		 = 0 0
stat64("/Volumes/files/p10001-20000/p13001-14000/p13101-13200/13156/\0", 0x7FFEECD05960, 0x0)		 = 0 0
open("/Users/anja/Downloads/BekraeftelseFraTDC.pdf\0", 0x1000000, 0x1B6)		 = 327 0
fstat64(0x147, 0x7FFEECD05980, 0x0)		 = 0 0
flock(0x147, 0x5, 0x0)		 = 0 0
open("/Volumes/files/p10001-20000/p13001-14000/p13101-13200/13156/70493.pdf\0", 0x1000202, 0x1B6)		 = -1 1
psynch_cvsignal(0x7FDD962B2278, 0x100, 0x0)		 = 257 0
flock(0x147, 0x8, 0x0)		 = 0 0
close(0x147)		 = 0 0
sendto(0x67, 0x1835D5CB8, 0xE)		 = 14 0
recvmsg(0x67, 0x7FFEECD00DF0, 0x0)		 = -1 35
gettimeofday(0x7FFEECD007E8, 0x0, 0x0)		 = 0 0
psynch_cvwait(0x7FDD962B2278, 0x100000100, 0x0)		 = 0 0
gettimeofday(0x70000ED08A18, 0x0, 0x0)		 = 0 0
kevent(0x68, 0x0, 0x0)		 = 2 0
psynch_cvsignal(0x7FDD9680EA78, 0x1560000015700, 0x15500)		 = 257 0
psynch_cvwait(0x7FDD9680EA78, 0x1560100015700, 0x15500)		 = 0 read0
psynch_cvsignal(0x7FDD969A8278, 0x260000002700, 0x2600)		 = 257 0
recvmsg(0x67, 0x7FFEECD00C80, 0x0)		 = 20 0
dtrace: error on enabled probe ID 2252 (ID 167: syscall::write:return): invalid kernel access in action #12 at DIF offset 68
dtrace: error on enabled probe ID 2252 (ID 167: syscall::write:return): invalid kernel access in action #12 at DIF offset 68
psynch_cvwait(0x7FDD969A8278, 0x260100002700, 0x2600)		 = 0 0
psynch_cvsignal(0x7FDD96217878, 0x310000003200, 0x3100)		 = 257 0
psynch_cvsignal(0x7FDD958E1E78, 0x5E0000005F00, 0x5E00)		 = 257 0
psynch_cvsignal(0x7FDD968D9478, 0x1F0000002000, 0x1F00)		 = 257 0
dtrace: error on enabled probe ID 2252 (ID 167: syscall::write:return): invalid kernel access in action #12 at DIF offset 68
psynch_cvwait(0x7FDD96217878, 0x310100003200, 0x3100)		 = 0 0
psynch_cvwait(0x7FDD958E1E78, 0x5E0100005F00, 0x5E00)		 = 0 0
psynch_cvwait(0x7FDD968D9478, 0x1F0100002000, 0x1F00)		 = 0 0
...

[mikkeljohnsen]

@jozkee Could you try using this code:

			var sourceUri = new Uri(sourceFile);
			var destUri = new Uri(destFile);

			byte[] buffer = new byte[BufferSize];

			using (FileStream sourceStream = File.OpenRead(sourceUri.LocalPath))
			{
				using (FileStream destinationStream = File.Create(destUri.LocalPath))
				{
					long remaining = sourceStream.Length;

					while (remaining > 0)
					{
						int read = await sourceStream.ReadAsync(buffer, 0, BufferSize, token);
						if (token.IsCancellationRequested) return 0;

						if (read <= 0)
							throw new EndOfStreamException();

						await destinationStream.WriteAsync(buffer, 0, read, token);
						if (token.IsCancellationRequested) return 0;

						remaining -= read;

						total += read;

						//progress?.Report(total);
					}
				}
			}