Wireshark-commits: [Wireshark-commits] master efe2926: NFS: Fix hash table key memory corruption

From: Wireshark code review <code-review-do-not-reply@xxxxxxxxxxxxx>
Date: Mon, 26 Aug 2019 05:31:45 +0000
URL: https://code.wireshark.org/review/gitweb?p=wireshark.git;a=commit;h=efe2926a66d3d7187a260226678daeb2aa6e4832
Submitter: "Anders Broman <a.broman58@xxxxxxxxx>"
Changed: branch: master
Repository: wireshark

Commits:

efe2926 by Tomasz Moń (desowin@xxxxxxxxx):

    NFS: Fix hash table key memory corruption
    
    When the same (as determined by key_equal_func) key gets added to the
    GHashTable, old value gets freed and replaced with the new one. This is
    fine for hash tables where the key validity is not tightly coupled to
    the actual data.
    
    In the nfs_name_snoop_matched hash table the key becomes invalid once
    the value gets destroyed (because it shares the data pointed to by fh,
    which gets freed once the value is destroyed).
    
    A problematic capture includes packets such that the matching fh gets
    added twice to the nfs_name_snoop_matched hash table. Prior to this
    change the hash table would end up in a state where the new value is
    associated with the old key (which contains pointer to already freed
    memory). According to the nfs_name_snoop_matched_equal(), the old key
    was equal to the key intended for new value *at the time* of insertion.
    
    This change fixes the bug by using g_hash_table_replace() which does
    update the key in case it already exists in the GHashTable.
    
    Bug: 16017
    Bug: 16019
    Change-Id: Ib3943f1e27e82c05d9abaa1e436554b37a98488e
    Reviewed-on: https://code.wireshark.org/review/34360
    Reviewed-by: Michael Mann <mmann78@xxxxxxxxxxxx>
    Petri-Dish: Michael Mann <mmann78@xxxxxxxxxxxx>
    Tested-by: Petri Dish Buildbot
    Reviewed-by: Anders Broman <a.broman58@xxxxxxxxx>
    

Actions performed:

    from  35056a6   SIP: Ensure session-id is not empty
     add  efe2926   NFS: Fix hash table key memory corruption


Summary of changes:
 epan/dissectors/packet-nfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)