Potential segfault in the time crate

2020-11-18T12:00:00
ID OSV:RUSTSEC-2020-0071
Type osv
Reporter Google
Modified 2021-10-19T22:13:58

Description

Impact

Unix-like operating systems may segfault due to dereferencing a dangling pointer in specific circumstances. This requires an environment variable to be set in a different thread than the affected functions. This may occur without the user's knowledge, notably in a third-party library.

The affected functions from time 0.2.7 through 0.2.22 are:

  • time::UtcOffset::local_offset_at
  • time::UtcOffset::try_local_offset_at
  • time::UtcOffset::current_local_offset
  • time::UtcOffset::try_current_local_offset
  • time::OffsetDateTime::now_local
  • time::OffsetDateTime::try_now_local

The affected functions in time 0.1 (all versions) are:

  • at
  • at_utc
  • now

Non-Unix targets (including Windows and wasm) are unaffected.

Patches

Pending a proper fix, the internal method that determines the local offset has been modified to always return None on the affected operating systems. This has the effect of returning an Err on the try_* methods and UTC on the non-try_* methods.

Users and library authors with time in their dependency tree should perform cargo update, which will pull in the updated, unaffected code.

Users of time 0.1 do not have a patch and should upgrade to an unaffected version: time 0.2.23 or greater or the 0.3 series.

Workarounds

No workarounds are known.

References

time-rs/time#293