SSSD / sssd

#3571 mmap cache: consistency check might fail if there are hash collisions
Closed: Fixed Opened by sbose.

Closed: Fixed
Reopen Issue

The consistency checks for the memory cache records might lead to a false corruption detection if there is a hash collision.

E.g. if there is a hash collision between an entry with a very short name and another entry with a very long name the check in sss_mc_find_record()

    if (key->len > strs_len
        || (name_ptr + key->len) > (strs_offset + strs_len)
        || (uint8_t *)rec->data + strs_offset + strs_len > max_addr) {

might fail if the entry with the short name is the first one found and key->len of the long (fully-qualified) name is larger then all strings of the entry with the sort name (gecos and shell might be empty).

This will cause an unneeded sss_mmap_cache_reset().

The checks including key->len should be removed at this point or the string comparison should be done before the consistency check best witn strncmp() and a suitable choosen size.

https://github.com/SSSD/sssd/pull/455

Metadata Update from @sbose:
- Custom field patch adjusted to on

Metadata Update from @jhrozek:
- Issue set to the milestone: SSSD 1.16.1
- Issue tagged with: PR, bug

Metadata Update from @jhrozek:
- Issue assigned to sbose

Metadata Update from @sbose:
- Custom field rhbz adjusted to https://bugzilla.redhat.com/show_bug.cgi?id=1490120

Issue linked to Bugzilla: Bug 1490120

And maybe also https://bugzilla.redhat.com/show_bug.cgi?id=1326007. We can link BZ later after confirmation that fix works.

master:

  • 4382047490dd4f80b407cc1e618da048f13e5f8f

Additional fix from patchset for regression test

master:

  • fd17e0925dbcafedb878ddf828a37743c115c9dd
Edited by lslebodn

Since the PRs were merged, I'm going to close this ticket. Feel free to push back if this ticket was in fact waiting for another fix, but according to the PR, we're just waiting for a confirmation about sssd-1-13 backport.

Metadata Update from @jhrozek:
- Issue priority set to: critical

sssd-1-14:

  • 1b70f422c99664ae3de22fc7100ca3a57139152f

sssd-1-13:

  • 5b0d4d85e1ea6d5102aaf0f3fe9fc7a4d942c414

SSSD is moving from Pagure to Github. This means that new issues and pull requests
will be accepted only in SSSD's github repository.

This issue has been cloned to Github and is available here:
- https://github.com/SSSD/sssd/issues/4595

If you want to receive further updates on the issue, please navigate to the github issue
and click on subscribe button.

Thank you for understanding. We apologize for all inconvenience.
Metadata

PR bug

None
None
Low
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