{"id":"CVE-2026-52941","summary":"net/smc: avoid NULL deref of conn-\u003elnk in smc_msg_event tracepoint","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: avoid NULL deref of conn-\u003elnk in smc_msg_event tracepoint\n\nThe smc_msg_event tracepoint class, shared by smc_tx_sendmsg and\nsmc_rx_recvmsg, unconditionally dereferences smc-\u003econn.lnk:\n\n\t__string(name, smc-\u003econn.lnk-\u003eibname)\n\nconn-\u003elnk is only set for SMC-R; for SMC-D it is NULL. Other code on\nthese paths already handles this (e.g. !conn-\u003elnk in\nSMC_STAT_RMB_TX_SIZE_SMALL()). With the tracepoint enabled, the first\nsendmsg()/recvmsg() on an SMC-D socket crashes:\n\n  Oops: general protection fault, probably for non-canonical address\n  KASAN: null-ptr-deref in range [...]\n  RIP: 0010:strlen+0x1e/0xa0\n  Call Trace:\n   trace_event_raw_event_smc_msg_event (net/smc/smc_tracepoint.h:44)\n   smc_rx_recvmsg (net/smc/smc_rx.c:515)\n   smc_recvmsg (net/smc/af_smc.c:2859)\n   __sys_recvfrom (net/socket.c:2315)\n   __x64_sys_recvfrom (net/socket.c:2326)\n   do_syscall_64\n\nThe faulting address 0x3e0 is offsetof(struct smc_link, ibname),\nconfirming the NULL -\u003elnk deref. Enabling the tracepoint requires\nroot, but the trigger itself is unprivileged: socket(AF_SMC, ...) has\nno capability check, and SMC-D negotiation needs no admin step on\ns390 or on x86 with the loopback ISM device loaded.\n\nLog an empty device name for SMC-D instead of dereferencing NULL.","modified":"2026-07-10T03:53:50.248903202Z","published":"2026-06-24T07:14:29.943Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52941.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/561cf66fa9b6c86dfe4e687d2d1aeaaa6739917f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/68200112534bb2acd1d7117dc2d5c124868d866d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/720c76b930c52cd58f50eb6b10569d03dccc7959"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7bf563badd37cb796df5477d2b78bb64148a1268"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b706d6d76a2a2793fe5ad0fbc2a75b6a460094ef"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d2ea0b8aef8746e147602eac87ca8538f4bc7e66"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52941.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52941"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"aff3083f10bff7a37eaa2b4e6bc5fb627ddd5f84"},{"fixed":"68200112534bb2acd1d7117dc2d5c124868d866d"},{"fixed":"720c76b930c52cd58f50eb6b10569d03dccc7959"},{"fixed":"b706d6d76a2a2793fe5ad0fbc2a75b6a460094ef"},{"fixed":"d2ea0b8aef8746e147602eac87ca8538f4bc7e66"},{"fixed":"561cf66fa9b6c86dfe4e687d2d1aeaaa6739917f"},{"fixed":"7bf563badd37cb796df5477d2b78bb64148a1268"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52941.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.175"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.142"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.92"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.34"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52941.json"}}],"schema_version":"1.7.5"}