--- title: Retiring BSD-Compress Proposed For Linux PPP Network Code description: A patch proposes removing BSD-Compress support from the Linux kernel's PPP networking code. The decoder assumes a 32-bit accumulator but declares it as... canonical: https://daily.dev/posts/retiring-bsd-compress-proposed-for-linux-ppp-network-code-n6mvsukhi twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Retiring BSD-Compress Proposed For Linux PPP Network Code | daily.dev og:description: A patch proposes removing BSD-Compress support from the Linux kernel's PPP networking code. The decoder assumes a 32-bit accumulator but declares it as... og:url: https://daily.dev/posts/retiring-bsd-compress-proposed-for-linux-ppp-network-code-n6mvsukhi og:image: https://api.daily.dev/og/posts/N6mVSUkhi.png og:image:alt: Retiring BSD-Compress Proposed For Linux PPP Network Code og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Retiring BSD-Compress Proposed For Linux PPP Network Code **[Phoronix](https://daily.dev/sources/phoronix)** · 2 min read · 0 upvotes · 0 comments ## Summary A patch proposes removing BSD-Compress support from the Linux kernel's PPP networking code. The decoder assumes a 32-bit accumulator but declares it as unsigned long, so on 64-bit systems leftover bits corrupt the next code. An x86-64 PPP-over-PTY loopback test reproduces a fatal bad-code error on the first compressed packet, after which pppd disables compression and the link continues uncompressed. The compression routine hasn't changed since Linux 2.1.67 (1997) and the decompression routine since Linux 1.3.33 (1995). A 2024 review suggested unsigned int, and the decoder still uses unsigned long. The PPP drivers and compressors are orphaned in the kernel, and the removal patch is pending on the netdev mailing list. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Why does BSD-Compress for PPP fail on 64-bit Linux systems? The BSD-Compress decoder assumes a 32-bit accumulator but declares it as 'unsigned long', so on 64-bit systems leftover bits from previous shifts survive and corrupt the next code. An x86-64 PPP-over-PTY loopback test reproduces a fatal bad-code error on the first compressed packet, causing pppd to disable compression and log 'Lost compression sync: disabling compression'. _Developers maintaining legacy PPP or networking stacks can follow kernel patch discussions like this on daily.dev._ ### Is the Linux kernel's PPP code still actively maintained? No, the PPP protocol drivers and compressors are orphaned within the Linux kernel. The BSD-Compress compression routine hasn't changed since Linux 2.1.67 in 1997, and the decompression routine since Linux 1.3.33 in 1995, with only module integration, kernel API, and allocation hardening updates since then. _Anyone relying on orphaned kernel subsystems can track removal proposals like this one via daily.dev._ ## Similar posts on daily.dev - [Patches Provide For Much Faster In-Kernel Zstd Due To Embarrassingly Bad Inefficiency](https://daily.dev/posts/patches-provide-for-much-faster-in-kernel-zstd-due-to-embarrassingly-bad-inefficiency-zshp9rw2o) · Phoronix · 1 upvotes · 0 comments - [Zstd Improvement For Linux 7.4 To Avoid Redundant Initialization](https://daily.dev/posts/zstd-improvement-for-linux-7-4-to-avoid-redundant-initialization-vmxghhcdw) · Phoronix · 0 upvotes · 0 comments - [Big Fish: Exploiting a 37-Year-Old Kernel Bug in OpenBSD](https://daily.dev/posts/big-fish-exploiting-a-37-year-old-kernel-bug-in-openbsd-u6hc8g4lt) · Hacker News · 0 upvotes · 0 comments - [CVE-2026-14266: Inside the 7-Zip Heap Overflow Hiding in XZ Archives Since 2021](https://daily.dev/posts/cve-2026-14266-inside-the-7-zip-heap-overflow-hiding-in-xz-archives-since-2021-bfyx6nvg2) · Latest Hacking News · 0 upvotes · 0 comments --- Tags: [#linux](https://daily.dev/tags/linux), [#networking](https://daily.dev/tags/networking) [View this post on daily.dev](https://daily.dev/posts/retiring-bsd-compress-proposed-for-linux-ppp-network-code-n6mvsukhi) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Retiring BSD-Compress Proposed For Linux PPP Network Code","url":"https://daily.dev/posts/retiring-bsd-compress-proposed-for-linux-ppp-network-code-n6mvsukhi","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/retiring-bsd-compress-proposed-for-linux-ppp-network-code-n6mvsukhi"},"datePublished":"2026-10-28T10:05:39.336Z","dateModified":"2026-10-28T10:08:44.928Z","description":"A patch proposes removing BSD-Compress support from the Linux kernel's PPP networking code. 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An x86-64 PPP-over-PTY loopback test reproduces a fatal bad-code error on the first compressed packet, causing pppd to disable compression and log 'Lost compression sync: disabling compression'. Developers maintaining legacy PPP or networking stacks can follow kernel patch discussions like this on daily.dev."}},{"@type":"Question","name":"Is the Linux kernel's PPP code still actively maintained?","acceptedAnswer":{"@type":"Answer","text":"No, the PPP protocol drivers and compressors are orphaned within the Linux kernel. The BSD-Compress compression routine hasn't changed since Linux 2.1.67 in 1997, and the decompression routine since Linux 1.3.33 in 1995, with only module integration, kernel API, and allocation hardening updates since then. Anyone relying on orphaned kernel subsystems can track removal proposals like this one via daily.dev."}}]} ```