{"id":"CVE-2026-74719","state":"PUBLISHED","title":"net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler()\n\nThe SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT branch in\nsmc_llc_event_handler() stores an incoming qentry into the local LLC flow\nwithout first checking whether a qentry is already pending. If a malicious or\nbuggy peer sends a second CONFIRM_LINK or ADD_LINK_CONT request while a flow is\nactive and flow->qentry is already set, smc_llc_flow_qentry_set() overwrites the\npointer without freeing the previous allocation, leaking one kmalloc-96 object\nper spurious message.\n\nThe sibling SMC_LLC_DELETE_LINK branch already has the correct !flow->qentry\nguard. Apply the same guard to the CONFIRM_LINK/ADD_LINK_CONT branch so that a\nduplicate message when qentry is already occupied falls through to break and is\nfreed by the kfree(qentry) at the out: label, rather than silently leaking the\nexisting allocation.\n\nThe response direction (smc_llc_rx_response()) is unaffected: it already guards\nwith flow->qentry at the equivalent site and drops duplicate responses\ncorrectly.","publishedAt":"2026-08-22T15:33:12.716Z","updatedAt":"2026-08-22T15:33:12.716Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"e384f3cba6ea709f5b2272b1770db4ce14047f78","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"a1e980d7a9e7ee6faf4f5fd7b450413b969af26d","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"e0eb87677c76b157cdf8eb7c1f19e56227165a33","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"06734dfeaeba886aab1bf147249195b888ac3e4d","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"c23c409228629107203d3c3e95fff1473173f1a6","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"10cb31b2b74cb664c6c95cf72364d7d5c483ab82","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"bfc336a9fbbf09805f3dfe25c195a4db90af2846","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"976245094925bab9bc39366b2e9ab44ffcde61d0","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_llc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.8","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.8","versionType":"semver"},{"version":"5.10.265","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.216","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.152","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.104","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.45","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.9","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_llc.c"]}],"references":["https://git.kernel.org/stable/c/e384f3cba6ea709f5b2272b1770db4ce14047f78","https://git.kernel.org/stable/c/a1e980d7a9e7ee6faf4f5fd7b450413b969af26d","https://git.kernel.org/stable/c/e0eb87677c76b157cdf8eb7c1f19e56227165a33","https://git.kernel.org/stable/c/06734dfeaeba886aab1bf147249195b888ac3e4d","https://git.kernel.org/stable/c/c23c409228629107203d3c3e95fff1473173f1a6","https://git.kernel.org/stable/c/10cb31b2b74cb664c6c95cf72364d7d5c483ab82","https://git.kernel.org/stable/c/bfc336a9fbbf09805f3dfe25c195a4db90af2846","https://git.kernel.org/stable/c/976245094925bab9bc39366b2e9ab44ffcde61d0"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74719.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74719","state":"PUBLISHED","datePublished":"2026-08-22T15:33:12.716Z","dateUpdated":"2026-08-22T15:33:12.716Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.929Z"},"containers":{"cna":{"title":"net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler()\n\nThe SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT branch in\nsmc_llc_event_handler() stores an incoming qentry into the local LLC flow\nwithout first checking whether a qentry is already pending. If a malicious or\nbuggy peer sends a second CONFIRM_LINK or ADD_LINK_CONT request while a flow is\nactive and flow->qentry is already set, smc_llc_flow_qentry_set() overwrites the\npointer without freeing the previous allocation, leaking one kmalloc-96 object\nper spurious message.\n\nThe sibling SMC_LLC_DELETE_LINK branch already has the correct !flow->qentry\nguard. Apply the same guard to the CONFIRM_LINK/ADD_LINK_CONT branch so that a\nduplicate message when qentry is already occupied falls through to break and is\nfreed by the kfree(qentry) at the out: label, rather than silently leaking the\nexisting allocation.\n\nThe response direction (smc_llc_rx_response()) is unaffected: it already guards\nwith flow->qentry at the equivalent site and drops duplicate responses\ncorrectly."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"e384f3cba6ea709f5b2272b1770db4ce14047f78","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"a1e980d7a9e7ee6faf4f5fd7b450413b969af26d","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"e0eb87677c76b157cdf8eb7c1f19e56227165a33","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"06734dfeaeba886aab1bf147249195b888ac3e4d","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"c23c409228629107203d3c3e95fff1473173f1a6","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"10cb31b2b74cb664c6c95cf72364d7d5c483ab82","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"bfc336a9fbbf09805f3dfe25c195a4db90af2846","versionType":"git"},{"version":"0fb0b02bd6fd26cba38002be4a6bbcae2228fd44","status":"affected","lessThan":"976245094925bab9bc39366b2e9ab44ffcde61d0","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_llc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.8","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.8","versionType":"semver"},{"version":"5.10.265","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.216","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.152","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.104","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.45","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.9","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_llc.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/e384f3cba6ea709f5b2272b1770db4ce14047f78"},{"url":"https://git.kernel.org/stable/c/a1e980d7a9e7ee6faf4f5fd7b450413b969af26d"},{"url":"https://git.kernel.org/stable/c/e0eb87677c76b157cdf8eb7c1f19e56227165a33"},{"url":"https://git.kernel.org/stable/c/06734dfeaeba886aab1bf147249195b888ac3e4d"},{"url":"https://git.kernel.org/stable/c/c23c409228629107203d3c3e95fff1473173f1a6"},{"url":"https://git.kernel.org/stable/c/10cb31b2b74cb664c6c95cf72364d7d5c483ab82"},{"url":"https://git.kernel.org/stable/c/bfc336a9fbbf09805f3dfe25c195a4db90af2846"},{"url":"https://git.kernel.org/stable/c/976245094925bab9bc39366b2e9ab44ffcde61d0"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-22T15:33:12.716Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"5.10.265"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"5.15.216"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.1.183"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.6.152"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.12.104"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.18.45"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"7.1.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}