{"id":"CVE-2026-23277","state":"PUBLISHED","title":"net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit\n\nteql_master_xmit() calls netdev_start_xmit(skb, slave) to transmit\nthrough slave devices, but does not update skb->dev to the slave device\nbeforehand.\n\nWhen a gretap tunnel is a TEQL slave, the transmit path reaches\niptunnel_xmit() which saves dev = skb->dev (still pointing to teql0\nmaster) and later calls iptunnel_xmit_stats(dev, pkt_len). This\nfunction does:\n\n    get_cpu_ptr(dev->tstats)\n\nSince teql_master_setup() does not set dev->pcpu_stat_type to\nNETDEV_PCPU_STAT_TSTATS, the core network stack never allocates tstats\nfor teql0, so dev->tstats is NULL. get_cpu_ptr(NULL) computes\nNULL + __per_cpu_offset[cpu], resulting in a page fault.\n\n BUG: unable to handle page fault for address: ffff8880e6659018\n #PF: supervisor write access in kernel mode\n #PF: error_code(0x0002) - not-present page\n PGD 68bc067 P4D 68bc067 PUD 0\n Oops: Oops: 0002 [#1] SMP KASAN PTI\n RIP: 0010:iptunnel_xmit (./include/net/ip_tunnels.h:664 net/ipv4/ip_tunnel_core.c:89)\n Call Trace:\n  <TASK>\n  ip_tunnel_xmit (net/ipv4/ip_tunnel.c:847)\n  __gre_xmit (net/ipv4/ip_gre.c:478)\n  gre_tap_xmit (net/ipv4/ip_gre.c:779)\n  teql_master_xmit (net/sched/sch_teql.c:319)\n  dev_hard_start_xmit (net/core/dev.c:3887)\n  sch_direct_xmit (net/sched/sch_generic.c:347)\n  __dev_queue_xmit (net/core/dev.c:4802)\n  neigh_direct_output (net/core/neighbour.c:1660)\n  ip_finish_output2 (net/ipv4/ip_output.c:237)\n  __ip_finish_output.part.0 (net/ipv4/ip_output.c:315)\n  ip_mc_output (net/ipv4/ip_output.c:369)\n  ip_send_skb (net/ipv4/ip_output.c:1508)\n  udp_send_skb (net/ipv4/udp.c:1195)\n  udp_sendmsg (net/ipv4/udp.c:1485)\n  inet_sendmsg (net/ipv4/af_inet.c:859)\n  __sys_sendto (net/socket.c:2206)\n\nFix this by setting skb->dev = slave before calling\nnetdev_start_xmit(), so that tunnel xmit functions see the correct\nslave device with properly allocated tstats.","publishedAt":"2026-03-20T08:08:57.394Z","updatedAt":"2026-10-15T01:13:33.847Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"383493b9940e3d1b5517424081b3e072e20ec43c","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"6b1f563d670162e188a0f2aec39c24b67b106e17","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"57c153249143333bbf4ecf927bdf8aa2696ee397","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"59b06d8b9bdb6b64b3c534c18da68bce5ccd31be","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"81a43e8005366f16e629d8c95dfe05beaa8d36a7","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"0bad9c86edd22dec4df83c2b29872d66fd8a2ff4","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"21ea283c2750c8307aa35ee832b0951cc993c27d","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"0cc0c2e661af418bbf7074179ea5cfffc0a5c466","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_teql.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.5","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.78","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.19","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.9","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_teql.c"]}],"references":["https://git.kernel.org/stable/c/383493b9940e3d1b5517424081b3e072e20ec43c","https://git.kernel.org/stable/c/6b1f563d670162e188a0f2aec39c24b67b106e17","https://git.kernel.org/stable/c/57c153249143333bbf4ecf927bdf8aa2696ee397","https://git.kernel.org/stable/c/59b06d8b9bdb6b64b3c534c18da68bce5ccd31be","https://git.kernel.org/stable/c/81a43e8005366f16e629d8c95dfe05beaa8d36a7","https://git.kernel.org/stable/c/0bad9c86edd22dec4df83c2b29872d66fd8a2ff4","https://git.kernel.org/stable/c/21ea283c2750c8307aa35ee832b0951cc993c27d","https://git.kernel.org/stable/c/0cc0c2e661af418bbf7074179ea5cfffc0a5c466","https://cert-portal.siemens.com/productcert/html/ssa-082556.html","https://cert-portal.siemens.com/productcert/html/ssa-019113.html","https://cert-portal.siemens.com/productcert/html/ssa-457936.html","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":[],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/23xxx/CVE-2026-23277.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23277","state":"PUBLISHED","datePublished":"2026-03-20T08:08:57.394Z","dateUpdated":"2026-10-15T01:13:33.847Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:37:45.991Z"},"containers":{"cna":{"title":"net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit\n\nteql_master_xmit() calls netdev_start_xmit(skb, slave) to transmit\nthrough slave devices, but does not update skb->dev to the slave device\nbeforehand.\n\nWhen a gretap tunnel is a TEQL slave, the transmit path reaches\niptunnel_xmit() which saves dev = skb->dev (still pointing to teql0\nmaster) and later calls iptunnel_xmit_stats(dev, pkt_len). This\nfunction does:\n\n    get_cpu_ptr(dev->tstats)\n\nSince teql_master_setup() does not set dev->pcpu_stat_type to\nNETDEV_PCPU_STAT_TSTATS, the core network stack never allocates tstats\nfor teql0, so dev->tstats is NULL. get_cpu_ptr(NULL) computes\nNULL + __per_cpu_offset[cpu], resulting in a page fault.\n\n BUG: unable to handle page fault for address: ffff8880e6659018\n #PF: supervisor write access in kernel mode\n #PF: error_code(0x0002) - not-present page\n PGD 68bc067 P4D 68bc067 PUD 0\n Oops: Oops: 0002 [#1] SMP KASAN PTI\n RIP: 0010:iptunnel_xmit (./include/net/ip_tunnels.h:664 net/ipv4/ip_tunnel_core.c:89)\n Call Trace:\n  <TASK>\n  ip_tunnel_xmit (net/ipv4/ip_tunnel.c:847)\n  __gre_xmit (net/ipv4/ip_gre.c:478)\n  gre_tap_xmit (net/ipv4/ip_gre.c:779)\n  teql_master_xmit (net/sched/sch_teql.c:319)\n  dev_hard_start_xmit (net/core/dev.c:3887)\n  sch_direct_xmit (net/sched/sch_generic.c:347)\n  __dev_queue_xmit (net/core/dev.c:4802)\n  neigh_direct_output (net/core/neighbour.c:1660)\n  ip_finish_output2 (net/ipv4/ip_output.c:237)\n  __ip_finish_output.part.0 (net/ipv4/ip_output.c:315)\n  ip_mc_output (net/ipv4/ip_output.c:369)\n  ip_send_skb (net/ipv4/ip_output.c:1508)\n  udp_send_skb (net/ipv4/udp.c:1195)\n  udp_sendmsg (net/ipv4/udp.c:1485)\n  inet_sendmsg (net/ipv4/af_inet.c:859)\n  __sys_sendto (net/socket.c:2206)\n\nFix this by setting skb->dev = slave before calling\nnetdev_start_xmit(), so that tunnel xmit functions see the correct\nslave device with properly allocated tstats."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"383493b9940e3d1b5517424081b3e072e20ec43c","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"6b1f563d670162e188a0f2aec39c24b67b106e17","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"57c153249143333bbf4ecf927bdf8aa2696ee397","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"59b06d8b9bdb6b64b3c534c18da68bce5ccd31be","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"81a43e8005366f16e629d8c95dfe05beaa8d36a7","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"0bad9c86edd22dec4df83c2b29872d66fd8a2ff4","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"21ea283c2750c8307aa35ee832b0951cc993c27d","versionType":"git"},{"version":"039f50629b7f860f36644ed1f34b27da9aa62f43","status":"affected","lessThan":"0cc0c2e661af418bbf7074179ea5cfffc0a5c466","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_teql.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.5","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.78","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.19","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.9","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_teql.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/383493b9940e3d1b5517424081b3e072e20ec43c"},{"url":"https://git.kernel.org/stable/c/6b1f563d670162e188a0f2aec39c24b67b106e17"},{"url":"https://git.kernel.org/stable/c/57c153249143333bbf4ecf927bdf8aa2696ee397"},{"url":"https://git.kernel.org/stable/c/59b06d8b9bdb6b64b3c534c18da68bce5ccd31be"},{"url":"https://git.kernel.org/stable/c/81a43e8005366f16e629d8c95dfe05beaa8d36a7"},{"url":"https://git.kernel.org/stable/c/0bad9c86edd22dec4df83c2b29872d66fd8a2ff4"},{"url":"https://git.kernel.org/stable/c/21ea283c2750c8307aa35ee832b0951cc993c27d"},{"url":"https://git.kernel.org/stable/c/0cc0c2e661af418bbf7074179ea5cfffc0a5c466"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T22:03:45.245Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5","versionEndExcluding":"6.1.167"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5","versionEndExcluding":"6.12.78"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5","versionEndExcluding":"6.18.19"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5","versionEndExcluding":"6.19.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"affected":[{"vendor":"Siemens","product":"SIMATIC 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