Aspnetcode run with non-root user in linux

Question

I'm trying to run a veery simple hello world aspnetcore application inside a docker image (that inherits from microsoft/aspnetcore) with non-root user and I'm getting this error:

crit: Microsoft.AspNetCore.Server.Kestrel[0] Unable to start Kestrel. System.AggregateException: One or more errors occurred. (Error -13 EACCES permission denied) ---> Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.UvException: Error -13 EACCES permission denied at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.Libuv.ThrowError(Int32 statusCode) at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.Libuv.tcp_bind(UvTcpHandle handle, SockAddr& addr, Int32 flags) at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.UvTcpHandle.Bind(ServerAddress address) at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.TcpListenerPrimary.CreateListenSocket() at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Listener.b__8_0(Object state) --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.ListenerPrimary.d__12.MoveNext() --- End of inner exception stack trace --- at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions) at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken) at Microsoft.AspNetCore.Server.Kestrel.Internal.KestrelEngine.CreateServer(ServerAddress address) at Microsoft.AspNetCore.Server.Kestrel.KestrelServer.Start[TContext](IHttpApplication`1 application) ---> (Inner Exception #0) Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.UvException: Error -13 EACCES permission denied at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.Libuv.ThrowError(Int32 statusCode) at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.Libuv.tcp_bind(UvTcpHandle handle, SockAddr& addr, Int32 flags) at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.UvTcpHandle.Bind(ServerAddress address) at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.TcpListenerPrimary.CreateListenSocket() at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Listener.b__8_0(Object state) --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.ListenerPrimary.d__12.MoveNext()<---

It seems that aspnetcore could not be run without root permissions, and in some scenarios with very restricted security policies root user is not allow to run the main process of a docker image.

Is it any way to run aspnetcore application in linux with non-root user?

Sudo option is not valid becuase the same security policy.

Thanks,

Answer 1

Finally the problem was that I was trying to use port 80 for binding my app. If you use higher ports, ie, 5000. There are no problems with permissions.