Fix possible LogMessage-related crash (NVTable) #1970
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Subtracting an out-of-boundary number from a pointer is undefined. The result may underflow causing a crash. Signed-off-by: László Várady <laszlo.varady@balabit.com>
furiel
approved these changes
Apr 6, 2018
|
success |
MrAnno
changed the title
bazsi
approved these changes
Apr 7, 2018
|
Indeed good catch, and I guess it was very difficult to diagnose. Nice job! |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Subtracting an "out-of-boundary" number from a pointer is undefined.
The result may underflow making the condition false, causing a crash.
(
alloc_sizeis the size of a new entry that we want to store in NVTable.)Apart from this, my change is an equivalent transformation.
This bug has been identified on a Solaris 11 machine, where
NVTableis often stored on low addresses.