prog,btf: explicitly refuse ambiguous AttachTo targets #897
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lmb
approved these changes
Jan 13, 2023
| @@ -891,6 +891,12 @@ func findTargetInKernel(name string, progType ProgramType, attachType AttachType | |||
| } | |||
| return module, id, nil | |||
| } | |||
| // See cilium/ebpf#894. Until we can disambiguate between equally-named kernel | |||
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This reads to me like we'll at some point be able to drop this. Based on your research, we will never be able to disambiguate in all cases, so this won't go away. I'd probably just drop the comment.
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There's been talks of including symbol addresses in Func, but I've suggested to also include source file names, otherwise users wouldn't be able to reliably specify (in ELF section names) which symbol they're interested in.
There are more than 500 (unique) ambiguous symbols in 6.1, so this is a pretty heavy limitation that should be lifted at some point.
See cilium#894 for more context. Explicitly refuse loading programs with multiple AttachTo candidates. BTF needs to carry more information to allow disambiguating between them. The kernel API likely needs to be extended to allow specifying which candidate to pick. Signed-off-by: Timo Beckers <timo@isovalent.com>
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See #894 for more context. Explicitly refuse loading programs with multiple AttachTo candidates. BTF needs to carry more information to allow disambiguating between them. The kernel API likely needs to be extended to allow specifying which candidate to pick.