fix(storage): bounds-check the file basename in PurgeUploads Walk callback#4860
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milosgajdos merged 1 commit intoApr 22, 2026
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…lback PurgeUploads' Walk callback split the visited path with path.Split and indexed file[0] immediately. path.Split returns an empty basename for paths that end in a trailing slash - in practice this happens when an S3 driver surfaces a bare directory (common prefix) with an empty Key. Indexing a zero-length string then panics with 'index out of range [0] with length 0' and takes down the whole PurgeUploads goroutine (distribution#4713). Guard the length before touching file[0] so a trailing-slash / empty-basename entry is simply skipped as 'not a reserved directory', which matches what the branch was trying to do anyway. Runtime behaviour for every non-empty entry is unchanged. Closes distribution#4713 Signed-off-by: SAY-5 <SAY-5@users.noreply.github.com>
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What
Fixes #4713.
PurgeUploads'
Walkcallback split the visited path withpath.Splitand then indexedfile[0]immediately.path.Splitreturns an empty basename for paths that end in a trailing slash - in practice this happens when an S3 driver surfaces a bare directory (common prefix) with an empty Key. Indexing a zero-length string panics withindex out of range [0] with length 0and takes down the whole PurgeUploads goroutine, as seen in the report's trace (purgeuploads.go:73→s3.go:1023).Fix
Guard the length before touching
file[0]so a trailing-slash / empty-basename entry is skipped as 'not a reserved directory' - matching what the branch was trying to do anyway. Runtime behaviour for every non-empty entry is unchanged; only the zero-length edge case stops crashing.Verification
Locally on macOS, go 1.26.2:
gofmt -s -l registry/storage/purgeuploads.go: cleango vet ./registry/storage/...: cleango test -count=1 -run TestPurge ./registry/storage/: passCloses #4713