CVE-2023-54181: In the Linux kernel, the following vulnerability has been resolved: bpf: Fix issue in verifying allow_ptr_leaks After we converted the capabilities of our net

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix issue in verifying allow_ptr_leaks After we converted the capabilities of our net

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix issue in verifying allow_ptr_leaks After we converted the capabilities of our networking-bpf program from cap_sys_admin to cap_net_admin+cap_bpf, our networking-bpf program failed to start. Because it failed the bpf verifier, and the error log is "R3 pointer comparison prohibited". A simple reproducer as follows, SEC("cls-ingress") int ingress(struct __sk_buff *skb) { struct iphdr *iph = (void *)(long)skb->data + sizeof(struct ethhdr); if ((long)(iph + 1) > (long)skb->data_end) return TC_ACT_STOLEN; return TC_ACT_OK; } Per discussion with Yonghong and Alexei [1], comparison of two packet pointers is not a pointer leak. This patch fixes it. Our local kernel is 6.1.y and we expect this fix to be backported to 6.1.y, so stable is CCed. [1]. https://lore.kernel.org/bpf/CAADnVQ+Nmspr7Si+pxWn8zkE7hX-7s93ugwC+94aXSy4uQ9vBg@mail.gmail.com/

Description from the National Vulnerability Database, published by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

What it means for a small business

Linux is on the computers, phones or browsers your team uses every day. Turn on automatic updates and restart: most of these fixes only take effect after a restart.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.20%, higher than 9% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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