Description
In the Linux kernel, the following vulnerability has been resolved: net: nfc: nci: Add parameter validation for packet data Syzbot reported an uninitialized value bug in nci_init_req, which was introduced by commit 5aca7966d2a7 ("Merge tag 'perf-tools-fixes-for-v6.17-2025-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools"). This bug arises due to very limited and poor input validation that was done at nic_valid_size(). This validation only validates the skb->len (directly reflects size provided at the userspace interface) with the length provided in the buffer itself (interpreted as NCI_HEADER). This leads to the processing of memory content at the address assuming the correct layout per what opcode requires there. This leads to the accesses to buffer of `skb_buff->data` which is not assigned anything yet. Following the same silent drop of packets of invalid sizes at `nic_valid_size()`, add validation of the data in the respective handlers and return error values in case of failure. Release the skb if error values are returned from handlers in `nci_nft_packet` and effectively do a silent drop Possible TODO: because we silently drop the packets, the call to `nci_request` will be waiting for completion of request and will face timeouts. These timeouts can get excessively logged in the dmesg. A proper handling of them may require to export `nci_request_cancel` (or propagate error handling from the nft packets handlers).
Product status
6a2968aaf50c7a22fced77a5e24aa636281efca8 (git) before 8fcc7315a10a84264e55bb65ede10f0af20a983f
6a2968aaf50c7a22fced77a5e24aa636281efca8 (git) before bfdda0123dde406dbff62e7e9136037e97998a15
6a2968aaf50c7a22fced77a5e24aa636281efca8 (git) before 0ba68bea1e356f466ad29449938bea12f5f3711f
6a2968aaf50c7a22fced77a5e24aa636281efca8 (git) before 74837bca0748763a77f77db47a0bdbe63b347628
6a2968aaf50c7a22fced77a5e24aa636281efca8 (git) before c395d1e548cc68e84584ffa2e3ca9796a78bf7b9
6a2968aaf50c7a22fced77a5e24aa636281efca8 (git) before 9c328f54741bd5465ca1dc717c84c04242fac2e1
3.2
Any version before 3.2
5.15.195 (semver)
6.1.156 (semver)
6.6.112 (semver)
6.12.53 (semver)
6.17.3 (semver)
6.18-rc1 (original_commit_for_fix)
References
git.kernel.org/...c/8fcc7315a10a84264e55bb65ede10f0af20a983f
git.kernel.org/...c/bfdda0123dde406dbff62e7e9136037e97998a15
git.kernel.org/...c/0ba68bea1e356f466ad29449938bea12f5f3711f
git.kernel.org/...c/74837bca0748763a77f77db47a0bdbe63b347628
git.kernel.org/...c/c395d1e548cc68e84584ffa2e3ca9796a78bf7b9
git.kernel.org/...c/9c328f54741bd5465ca1dc717c84c04242fac2e1
