_CFXMLInterface: account for possible nullptr return
#5082
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
|
@swift-ci please test |
|
CC: @jmschonfeld |
parkera
reviewed
Sep 6, 2024
| CFStringRef resultString = __CFSwiftXMLParserBridgeCF.CFStringCreateWithCString(NULL, (const char*)result, kCFStringEncodingUTF8); | ||
| CFStringRef resultString = NULL; | ||
| if (result) { | ||
| __CFSwiftXMLParserBridgeCF.CFStringCreateWithCString(NULL, (const char*)result, kCFStringEncodingUTF8); |
There was a problem hiding this comment.
Nit - inconsistent spacing in the file.
Is xmlFree(NULL) ok to call?
There was a problem hiding this comment.
Yes, AFAIK, xmlFree behaves as free, where nullptr as an argument is well defined.
|
@swift-ci please test Windows platform |
`xmlSplitQName2` may return `nullptr` for the result, which when passed to `CFStringCreateWithCString` would attempt to perform `strlen(nullptr)` which is ill-defined. When updating libxml2 on Windows, we would perform an invalid memory access due to the `strlen` invocation inside `CFStringCreateWithCString`. Protect against this case, returning `NULL` instead.
|
@swift-ci please test |
parkera
approved these changes
Sep 9, 2024
|
@swift-ci please test windows platform |
|
Any update |
|
Not pushing forward on this for the time being as the motivation behind this was behavioural changes in libxml2 2.13.x which has ABI breakages that are difficult to address. |
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Outdated suggestions cannot be applied.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.
xmlSplitQName2may returnnullptrfor the result, which when passed toCFStringCreateWithCStringwould attempt to performstrlen(nullptr)which is ill-defined. When updating libxml2 on Windows, we would perform an invalid memory access due to thestrleninvocation insideCFStringCreateWithCString. Protect against this case, returningNULLinstead.