iPhone7, iOS 14.2 Restore, ASR failure: Socket unexpectedly closed while trying to read() offset 0x3E0000

[fermulator]

Hi team!

As you probably get often, I've a failed iPhone 7, it tried to upgrade from iOS 14.1 to 14.2, and got stuck. Then it went into recovery mode boot loop.

I have tried this procedure on two different systems (Linux Mint 18.3, and Ubuntu 18.04), following all the necessary compilation/package installations.

ASR STATUS: restore
ASR: asr: 
ASR: Socket unexpectedly closed while trying to read() offset 0x3E0000
ASR: asr: Failed to read the stream: Input/output error
ASR: __decompressChunk: backing store read at offset 995473 length 225492 failed with error 5
ASR: __decompressChunk() error: 5
ASR STATUS: fail
ASR: Could not restore - Input/output error
ASR STATUS: fail
restore_apfs_image : failed to restore an APFS image, error = 14

That (I think) is the core error logs.

Full logs here: iphone7_idevicerestore_error_logs.txt

I used:

1. https://launchpad.net/~quamotion/+archive/ubuntu/ppa for pkgs
2. compiled idevicerestore, libimobiledevice, libirecovery

$ dpkg --list | egrep "liplist|libusb|usbmux|libidev"
ii  libgusb2:amd64                                                   0.2.11-1                                            amd64        GLib wrapper around libusb1
ii  libusb-0.1-4:amd64                                               2:0.1.12-31                                         amd64        userspace USB programming library
ii  libusb-0.1-4:i386                                                2:0.1.12-31                                         i386         userspace USB programming library
ii  libusb-1.0-0:amd64                                               2:1.0.21-2                                          amd64        userspace USB programming library
ii  libusb-1.0-0:i386                                                2:1.0.21-2                                          i386         userspace USB programming library
ii  libusb-1.0-0-dev:amd64                                           2:1.0.21-2                                          amd64        userspace USB programming library development files
ii  libusb-dev                                                       2:0.1.12-31                                         amd64        userspace USB programming library development files
ii  libusbmuxd-dev:amd64                                             2.0.3-1.3.6-0bionic                                 amd64        USB multiplexor daemon for iPhone and iPod Touch devices - devel
ii  libusbmuxd-tools                                                 2.0.3-1.3.6-0bionic                                 amd64        USB multiplexor daemon for iPhone and iPod Touch devices - tools
rc  libusbmuxd1                                                      1.0.7-2ubuntu0.1                                    amd64        USB multiplexor daemon for iPhone and iPod Touch devices - library
rc  libusbmuxd2                                                      1.0.8-2ubuntu1                                      amd64        USB multiplexor daemon for iPhone and iPod Touch devices - library
ii  libusbmuxd4:amd64                                                1.12.0-1.2.178-0bionic                              amd64        USB multiplexor daemon for iPhone and iPod Touch devices - library
ii  libusbmuxd6:amd64                                                2.0.3-1.3.6-0bionic                                 amd64        USB multiplexor daemon for iPhone and iPod Touch devices - library
ii  libusbredirhost1:amd64                                           0.7.1-1                                             amd64        Implementing the usb-host (*) side of a usbredir connection (runtime)
ii  libusbredirparser1:amd64                                         0.7.1-1                                             amd64        Parser for the usbredir protocol (runtime)
ii  usbmuxd                                                          1.1.2-1.3.6-0bionic                                 amd64        USB multiplexor daemon for iPhone and iPod Touch devices

[fermulator]

I found notes in https://github.com/libimobiledevice/idevicerestore/issues/364, noting a potential known issue in the send(); https://github.com/libimobiledevice/libusbmuxd/commit/73cb5c182e36e7aafcff8a8932b21c6ab5cae5a6 looks like a relevant workaround; (I think my version of libusbmuxd would not have that fix?)