Memory-safety fixes: uninitialized reads and a realloc leak#613
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Four sites used a value that may never have been set: - tape_get_pews leaves *pews unset on -LTFS_UNSUPPORTED, which the caller treats as non-fatal before computing pews + 10. - ltfs_profiler_set left ret unset when the volume had neither an iosched nor a device handle, then tested it. - _get_dump derived a transfer length from cap_buf without checking the READ BUFFER result, so a failed read produced a garbage length. - the ICU normalize helpers leave their output pointer unset on error, but the callers compared that pointer against the input (to decide whether to free a no-op result) before checking the return code, reading uninitialized memory and potentially leaking the input buffer. Initialize pews and ret, check the READ BUFFER result, and check the normalize return code before the pointer comparison in all five callers.
realloc was assigned back to priv.dk_list, so a failure overwrote the only pointer to the existing buffer with NULL and leaked it. Use a temporary and free the original on failure.
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Two commits:
tape_get_pewsleaves*pewsunset on-LTFS_UNSUPPORTEDwhile the caller computespews + 10;ltfs_profiler_settested an unsetretwhen the volume had neither an iosched nor a device handle;_get_dumpderived a transfer length fromcap_bufwithout checking the READ BUFFER result; the ICU normalize callers compared the output pointer against the input before checking the return code, reading uninitialized memory and potentially leaking the input buffer.reallocwas assigned straight back topriv.dk_list, so a failure overwrote the only pointer to the existing buffer with NULL and leaked it.