{"id":"CVE-2026-98592","state":"PUBLISHED","title":"net: spacemit: clear TX descriptor on fragment mapping failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: spacemit: clear TX descriptor on fragment mapping failure\n\nemac_tx_mem_map() writes TX_DESC_0_OWN into the ring descriptor for\nevery slot beyond old_head as soon as that slot's memset()'d local\ncopy is committed with \"*tx_desc_addr = tx_desc\", i.e. before the\nbuffers for that slot have necessarily all been mapped successfully.\nIf emac_tx_map_frag() then fails on a later fragment, the err_free_skb\npath calls emac_free_tx_buf() to unmap and drop the skb, but leaves\nthe already-written descriptor memory untouched, and tx_ring->head is\nnever advanced past old_head (the \"tx_ring->head = head\" store is\nskipped by the goto).\n\nSo a slot between old_head and the rolled-back head can be left with\nTX_DESC_0_OWN set and buffer_addr_{1,2} pointing at DMA mappings that\nemac_free_tx_buf() just tore down, while software considers that slot\nfree again. The next successful emac_tx_mem_map() call only rebuilds\nold_head itself; if the DMA engine auto-advances into the following\ndescriptor once it finishes old_head's packet, it will fetch that\nstale, already-unmapped address.\n\nemac_tx_clean_desc() already treats emac_free_tx_buf() and clearing\nthe descriptor as a pair when reclaiming completed descriptors; do\nthe same in the mapping failure path.","publishedAt":"2026-10-18T15:19:04.373Z","updatedAt":"2026-10-19T09:22:17.811Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"bfec6d7f2001c7470c3cd261ae65a3ba8737f226","status":"affected","lessThan":"ca9986cc824f2feb79b4a83e5f6f4c24c2140448","versionType":"git"},{"version":"bfec6d7f2001c7470c3cd261ae65a3ba8737f226","status":"affected","lessThan":"3001a103a367c6051c43aff363b6979c10e65347","versionType":"git"},{"version":"bfec6d7f2001c7470c3cd261ae65a3ba8737f226","status":"affected","lessThan":"2d14720beb58870b15a52b236c3ab0be0e06e915","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/spacemit/k1_emac.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"6.18.55","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/spacemit/k1_emac.c"]}],"references":["https://git.kernel.org/stable/c/ca9986cc824f2feb79b4a83e5f6f4c24c2140448","https://git.kernel.org/stable/c/3001a103a367c6051c43aff363b6979c10e65347","https://git.kernel.org/stable/c/2d14720beb58870b15a52b236c3ab0be0e06e915"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98592.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98592","state":"PUBLISHED","datePublished":"2026-10-18T15:19:04.373Z","dateUpdated":"2026-10-19T09:22:17.811Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.359Z"},"containers":{"cna":{"title":"net: spacemit: clear TX descriptor on fragment mapping failure","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: spacemit: clear TX descriptor on fragment mapping failure\n\nemac_tx_mem_map() writes TX_DESC_0_OWN into the ring descriptor for\nevery slot beyond old_head as soon as that slot's memset()'d local\ncopy is committed with \"*tx_desc_addr = tx_desc\", i.e. before the\nbuffers for that slot have necessarily all been mapped successfully.\nIf emac_tx_map_frag() then fails on a later fragment, the err_free_skb\npath calls emac_free_tx_buf() to unmap and drop the skb, but leaves\nthe already-written descriptor memory untouched, and tx_ring->head is\nnever advanced past old_head (the \"tx_ring->head = head\" store is\nskipped by the goto).\n\nSo a slot between old_head and the rolled-back head can be left with\nTX_DESC_0_OWN set and buffer_addr_{1,2} pointing at DMA mappings that\nemac_free_tx_buf() just tore down, while software considers that slot\nfree again. The next successful emac_tx_mem_map() call only rebuilds\nold_head itself; if the DMA engine auto-advances into the following\ndescriptor once it finishes old_head's packet, it will fetch that\nstale, already-unmapped address.\n\nemac_tx_clean_desc() already treats emac_free_tx_buf() and clearing\nthe descriptor as a pair when reclaiming completed descriptors; do\nthe same in the mapping failure path."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"bfec6d7f2001c7470c3cd261ae65a3ba8737f226","status":"affected","lessThan":"ca9986cc824f2feb79b4a83e5f6f4c24c2140448","versionType":"git"},{"version":"bfec6d7f2001c7470c3cd261ae65a3ba8737f226","status":"affected","lessThan":"3001a103a367c6051c43aff363b6979c10e65347","versionType":"git"},{"version":"bfec6d7f2001c7470c3cd261ae65a3ba8737f226","status":"affected","lessThan":"2d14720beb58870b15a52b236c3ab0be0e06e915","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/spacemit/k1_emac.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"6.18.55","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/spacemit/k1_emac.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ca9986cc824f2feb79b4a83e5f6f4c24c2140448"},{"url":"https://git.kernel.org/stable/c/3001a103a367c6051c43aff363b6979c10e65347"},{"url":"https://git.kernel.org/stable/c/2d14720beb58870b15a52b236c3ab0be0e06e915"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:22:17.811Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"6.18.55"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"7.2.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}