RtlJaguarDevice: validate radiotap header length and read it_len as le16#38
Merged
Merged
Conversation
Two concerns left over from PR #31: 1. packet[2] was dereferenced with no check that length is large enough to hold the radiotap header. Bail early if length is smaller than sizeof(struct ieee80211_radiotap_header). 2. The radiotap it_len field is __le16 at bytes 2-3, not a single byte. Use get_unaligned_le16() to match Radiotap.c:215 and the IEEE80211_RADIOTAP_TX_FLAGS reader four lines down. Only caller is txdemo with a hardcoded local beacon, so this is defensive hardening rather than a deployed-system bug.
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
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Summary
Follow-up hardening on top of PR #31. Two concerns the PR #31 guard didn't cover:
packet[2]was dereferenced with no check thatlengthis large enough to hold the radiotap header. Bail early iflength < sizeof(struct ieee80211_radiotap_header).it_lenfield is__le16at bytes 2-3, not a single byte. Useget_unaligned_le16()to matchRadiotap.c:215and theIEEE80211_RADIOTAP_TX_FLAGSreader four lines down in the same function.Threat model: the only caller of
send_packetistxdemowith a hardcoded local beacon, so this is defensive hardening, not a deployed-system bug.Test plan
lengthwell abovesizeof(ieee80211_radiotap_header)andit_len = 0x0d)