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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"git__linenlen calls memchar with null pointer","articleBody":"### Reproduction steps\r\n`git__linenlen` in `util.c` calls memchar with null pointer passed as argument 1.  Can be reproduced with the following code:\r\n\r\n```\r\n#include \u003cgit2.h\u003e\r\n\r\nint main()\r\n{\r\n    git_repository *repo = NULL;\r\n\r\n    git_libgit2_init();\r\n    git_repository_init(\u0026repo, \"testrepo\", 0);\r\n    git_repository_free(repo);\r\n\r\n    return 0;\r\n}\r\n```\r\n\r\n### Expected behavior\r\n\r\nAvoid call to memchr with null pointer.\r\n\r\n### Actual behavior\r\n\r\nWhen I test memory access errors in the R bindings [git2r](https://github.com/ropensci/git2r) using Undefined Behavior Sanitizer, I see `libgit2/src/util.c:354:8: runtime error: null pointer passed as argument 1, which is declared to never be null`\r\n\r\n### Version of libgit2 (release number or SHA1)\r\n\r\n99bb98c0e8abb97b1daa3aff0307b93ed9291c08\r\n\r\n### Operating system(s) tested\r\n\r\nFedora 28","author":{"url":"https://github.com/stewid","@type":"Person","name":"stewid"},"datePublished":"2018-07-18T12:09:29.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/4726/libgit2/issues/4726"}