fix a bug in PerformBaseRelocation#116
Open
H4ckF0rFun wants to merge 1 commit intofancycode:masterfrom
Open
Conversation
Author
|
And in fact, it is not necessary to determine whether the end is reached based on whether the virtual address of the next block is 0 or not. directory_size and the size of each block are enough to tell if the end is reached. |
This file contains hidden or 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
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Bug
The end cannot be determined based on whether the Virtual Address of the next IMAGE_BASE_RELOCATION is 0 or not. In fact, it is possible that the next IMAGE_BASE_RELOCATION exceeds the size of the entire directory.
The data it contains is completely uncertain.
Instead, use directory size to determine if you've reached the end.
Sample:
By the time you get to the end, you have exceeded the size of the entire relocation table, and the memory after that is invalid, which will cause an exception if you use the Virtual Address
Why does this approach work most of the time?
The secetion in which the relocation table is located is page aligned, and in most cases there is memory for alignment behind the relocation table, which is filled with 0x00.