kernel: Don't require /proc/kcore access when only kallsyms is used#1561
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KernelResolver::new() unconditionally queried the KASLR offset, which reads /proc/kcore. If that fails with EPERM (common in containers or unprivileged processes), resolver creation hard-fails -- even though kallsyms-only symbolization doesn't need the offset at all, since kallsyms addresses are already relocated. Only query the KASLR offset when a vmlinux resolver is actually in use. The kallsyms-only path now works without /proc/kcore access; vmlinux based resolution still requires it since we can't correctly relocate addresses without the offset. Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## main #1561 +/- ##
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- Coverage 95.75% 95.74% -0.02%
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Files 56 56
Lines 9549 9550 +1
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Hits 9144 9144
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danielocfb
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May 21, 2026
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Looks good to me, thanks!
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KernelResolver::new()unconditionally queries the KASLR offset, which reads/proc/kcore. If that fails withEPERM(common in containers or for unprivileged processes), resolver creation hard-fails — even though kallsyms-only symbolization doesn't need the offset at all, since kallsyms addresses are already relocated.This change only queries the KASLR offset when a vmlinux resolver is actually in use. The kallsyms-only path now works without
/proc/kcoreaccess; vmlinux based resolution still requires it since we can't correctly relocate addresses without the offset.Also moves the "no symbol source" check above the offset query so we don't needlessly touch
/proc/kcorewhen we're about to error out anyway.