Score:0

Where does apt download kernel debugging symbols from?

us flag

Long story short: I need debugging symbols of various kernel versions for scientific purposes. (Memory forensics)

I followed some guide which lead me to executing:

$ apt-get install  --print-uris linux-image-$(uname -r)-dbgsym
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following NEW packages will be installed:
  linux-image-5.4.0-58-generic-dbgsym
0 upgraded, 1 newly installed, 0 to remove and 284 not upgraded.
Need to get 15,4 kB of archives.
After this operation, 22,5 kB of additional disk space will be used.
'http://ddebs.ubuntu.com/pool/main/l/linux-signed/linux-image-5.4.0-58-generic-dbgsym_5.4.0-58.64_amd64.ddeb' linux-image-5.4.0-58-generic-dbgsym_5.4.0-58.64_amd64.ddeb 15420 MD5Sum:abf99aad97774011358418df34d0c5f1

On my Ubuntu machine. And voilá: I got /usr/lib/debug/boot/vmlinux-5.4.0-58-generic on that machine.

However: When I directly download the url that apt-get printed there due to --print-uris, the deb file does not contain the debugging symbol file! I was hoping that I would find debugging symbols there AND debugging symbols for different version in the same folder. But it seems like none of them contain the actual dwarf file.

Any help would be much obliged.

Score:0
us flag

Please note that the package in question comes with dependencies:

# LANG=C dpkg -i linux-image-5.4.0-58-generic-dbgsym_5.4.0-58.64_amd64.ddeb 
Selecting previously unselected package linux-image-5.4.0-58-generic-dbgsym.
(Reading database ... 473483 files and directories currently installed.)
Preparing to unpack linux-image-5.4.0-58-generic-dbgsym_5.4.0-58.64_amd64.ddeb ...
Unpacking linux-image-5.4.0-58-generic-dbgsym (5.4.0-58.64) ...
dpkg: dependency problems prevent configuration of linux-image-5.4.0-58-generic-dbgsym:
 linux-image-5.4.0-58-generic-dbgsym depends on linux-image-unsigned-5.4.0-58-generic-dbgsym; however:
  Package linux-image-unsigned-5.4.0-58-generic-dbgsym is not installed.
[...]

You want to install the latter as well.

lo-na-aleim avatar
us flag
That actually led me to the right place! For the next guy, they are stored here: http://ddebs.ubuntu.com/pool/main/l/linux/
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