{"api_version":"1","generated_at":"2026-06-24T13:39:07+00:00","cve":"CVE-2026-52939","urls":{"html":"https://cve.report/CVE-2026-52939","api":"https://cve.report/api/cve/CVE-2026-52939.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-52939","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-52939"},"summary":{"title":"net/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked atomic completion","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked atomic completion\n\nrds_ib_xmit_atomic() always programs a masked atomic opcode\n(IB_WR_MASKED_ATOMIC_CMP_AND_SWP or IB_WR_MASKED_ATOMIC_FETCH_AND_ADD)\nfor every RDS atomic cmsg.  But the completion-side switch in\nrds_ib_send_unmap_op() only handles the non-masked opcodes, so a masked\natomic completion falls through to default and returns rm == NULL while\nsend->s_op is left set.  rds_ib_send_cqe_handler() then dereferences the\nNULL rm via rm->m_final_op, oopsing in softirq context.  An unprivileged\nAF_RDS sendmsg() of an atomic cmsg over an active RDS/IB connection\ntriggers it; on hardware that natively accepts masked atomics (mlx4,\nmlx5) no extra setup is needed.\n\n  RDS/IB: rds_ib_send_unmap_op: unexpected opcode 0xd in WR!\n  Oops: general protection fault [#1] SMP KASAN\n  KASAN: null-ptr-deref in range [0x0000000000000190-0x0000000000000197]\n  RIP: rds_ib_send_cqe_handler+0x25c/0xb10 (net/rds/ib_send.c:282)\n  Call Trace:\n   <IRQ>\n   rds_ib_send_cqe_handler (net/rds/ib_send.c:282)\n   poll_scq (net/rds/ib_cm.c:274)\n   rds_ib_tasklet_fn_send (net/rds/ib_cm.c:294)\n   tasklet_action_common (kernel/softirq.c:943)\n   handle_softirqs (kernel/softirq.c:573)\n   run_ksoftirqd (kernel/softirq.c:479)\n   </IRQ>\n  Kernel panic - not syncing: Fatal exception in interrupt\n\nHandle the masked atomic opcodes in the same case as the non-masked\nones: they map to the same struct rds_message.atomic union member, so\nthe existing container_of()/rds_ib_send_unmap_atomic() body is correct\nfor them.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-06-24 08:16:24","updated_at":"2026-06-24 08:16:24"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/4dd262f875e87653df50b138de1390ab0628e6b7","name":"https://git.kernel.org/stable/c/4dd262f875e87653df50b138de1390ab0628e6b7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/34080db3e70ddf94c38512ad2331e3c3afca6cc1","name":"https://git.kernel.org/stable/c/34080db3e70ddf94c38512ad2331e3c3afca6cc1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0f22412a2f4fbbe0251c132abee045d15a90e5b6","name":"https://git.kernel.org/stable/c/0f22412a2f4fbbe0251c132abee045d15a90e5b6","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4fd34669558085bcb589aa2078a13b0ca79e360d","name":"https://git.kernel.org/stable/c/4fd34669558085bcb589aa2078a13b0ca79e360d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6e4615164d185a26badb2f376a2449f4d174a5f0","name":"https://git.kernel.org/stable/c/6e4615164d185a26badb2f376a2449f4d174a5f0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/dcf458120add64c96a6ef5cf719340453f6e6abf","name":"https://git.kernel.org/stable/c/dcf458120add64c96a6ef5cf719340453f6e6abf","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0f7baa82a24813cdad0b06a6f8f07e4824af5ed5","name":"https://git.kernel.org/stable/c/0f7baa82a24813cdad0b06a6f8f07e4824af5ed5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a0148342badd8c9b2e46551766a27cb76c82e715","name":"https://git.kernel.org/stable/c/a0148342badd8c9b2e46551766a27cb76c82e715","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-52939","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52939","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20c72bd5f5f902e5a8745d51573699605bf8d21c a0148342badd8c9b2e46551766a27cb76c82e715 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20c72bd5f5f902e5a8745d51573699605bf8d21c 4dd262f875e87653df50b138de1390ab0628e6b7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20c72bd5f5f902e5a8745d51573699605bf8d21c 6e4615164d185a26badb2f376a2449f4d174a5f0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20c72bd5f5f902e5a8745d51573699605bf8d21c 0f22412a2f4fbbe0251c132abee045d15a90e5b6 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20c72bd5f5f902e5a8745d51573699605bf8d21c 0f7baa82a24813cdad0b06a6f8f07e4824af5ed5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20c72bd5f5f902e5a8745d51573699605bf8d21c dcf458120add64c96a6ef5cf719340453f6e6abf git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20c72bd5f5f902e5a8745d51573699605bf8d21c 4fd34669558085bcb589aa2078a13b0ca79e360d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20c72bd5f5f902e5a8745d51573699605bf8d21c 34080db3e70ddf94c38512ad2331e3c3afca6cc1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2.6.37","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 2.6.37 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.259 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.210 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.176 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.143 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.94 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.36 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.13 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/rds/ib_send.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"a0148342badd8c9b2e46551766a27cb76c82e715","status":"affected","version":"20c72bd5f5f902e5a8745d51573699605bf8d21c","versionType":"git"},{"lessThan":"4dd262f875e87653df50b138de1390ab0628e6b7","status":"affected","version":"20c72bd5f5f902e5a8745d51573699605bf8d21c","versionType":"git"},{"lessThan":"6e4615164d185a26badb2f376a2449f4d174a5f0","status":"affected","version":"20c72bd5f5f902e5a8745d51573699605bf8d21c","versionType":"git"},{"lessThan":"0f22412a2f4fbbe0251c132abee045d15a90e5b6","status":"affected","version":"20c72bd5f5f902e5a8745d51573699605bf8d21c","versionType":"git"},{"lessThan":"0f7baa82a24813cdad0b06a6f8f07e4824af5ed5","status":"affected","version":"20c72bd5f5f902e5a8745d51573699605bf8d21c","versionType":"git"},{"lessThan":"dcf458120add64c96a6ef5cf719340453f6e6abf","status":"affected","version":"20c72bd5f5f902e5a8745d51573699605bf8d21c","versionType":"git"},{"lessThan":"4fd34669558085bcb589aa2078a13b0ca79e360d","status":"affected","version":"20c72bd5f5f902e5a8745d51573699605bf8d21c","versionType":"git"},{"lessThan":"34080db3e70ddf94c38512ad2331e3c3afca6cc1","status":"affected","version":"20c72bd5f5f902e5a8745d51573699605bf8d21c","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/rds/ib_send.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"2.6.37"},{"lessThan":"2.6.37","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.259","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.210","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.176","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.143","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.94","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.36","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.13","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.259","versionStartIncluding":"2.6.37","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.210","versionStartIncluding":"2.6.37","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.176","versionStartIncluding":"2.6.37","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.143","versionStartIncluding":"2.6.37","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.94","versionStartIncluding":"2.6.37","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.36","versionStartIncluding":"2.6.37","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.13","versionStartIncluding":"2.6.37","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1","versionStartIncluding":"2.6.37","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked atomic completion\n\nrds_ib_xmit_atomic() always programs a masked atomic opcode\n(IB_WR_MASKED_ATOMIC_CMP_AND_SWP or IB_WR_MASKED_ATOMIC_FETCH_AND_ADD)\nfor every RDS atomic cmsg.  But the completion-side switch in\nrds_ib_send_unmap_op() only handles the non-masked opcodes, so a masked\natomic completion falls through to default and returns rm == NULL while\nsend->s_op is left set.  rds_ib_send_cqe_handler() then dereferences the\nNULL rm via rm->m_final_op, oopsing in softirq context.  An unprivileged\nAF_RDS sendmsg() of an atomic cmsg over an active RDS/IB connection\ntriggers it; on hardware that natively accepts masked atomics (mlx4,\nmlx5) no extra setup is needed.\n\n  RDS/IB: rds_ib_send_unmap_op: unexpected opcode 0xd in WR!\n  Oops: general protection fault [#1] SMP KASAN\n  KASAN: null-ptr-deref in range [0x0000000000000190-0x0000000000000197]\n  RIP: rds_ib_send_cqe_handler+0x25c/0xb10 (net/rds/ib_send.c:282)\n  Call Trace:\n   <IRQ>\n   rds_ib_send_cqe_handler (net/rds/ib_send.c:282)\n   poll_scq (net/rds/ib_cm.c:274)\n   rds_ib_tasklet_fn_send (net/rds/ib_cm.c:294)\n   tasklet_action_common (kernel/softirq.c:943)\n   handle_softirqs (kernel/softirq.c:573)\n   run_ksoftirqd (kernel/softirq.c:479)\n   </IRQ>\n  Kernel panic - not syncing: Fatal exception in interrupt\n\nHandle the masked atomic opcodes in the same case as the non-masked\nones: they map to the same struct rds_message.atomic union member, so\nthe existing container_of()/rds_ib_send_unmap_atomic() body is correct\nfor them."}],"providerMetadata":{"dateUpdated":"2026-06-24T07:14:28.622Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/a0148342badd8c9b2e46551766a27cb76c82e715"},{"url":"https://git.kernel.org/stable/c/4dd262f875e87653df50b138de1390ab0628e6b7"},{"url":"https://git.kernel.org/stable/c/6e4615164d185a26badb2f376a2449f4d174a5f0"},{"url":"https://git.kernel.org/stable/c/0f22412a2f4fbbe0251c132abee045d15a90e5b6"},{"url":"https://git.kernel.org/stable/c/0f7baa82a24813cdad0b06a6f8f07e4824af5ed5"},{"url":"https://git.kernel.org/stable/c/dcf458120add64c96a6ef5cf719340453f6e6abf"},{"url":"https://git.kernel.org/stable/c/4fd34669558085bcb589aa2078a13b0ca79e360d"},{"url":"https://git.kernel.org/stable/c/34080db3e70ddf94c38512ad2331e3c3afca6cc1"}],"title":"net/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked atomic completion","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-52939","datePublished":"2026-06-24T07:14:28.622Z","dateReserved":"2026-06-09T07:44:35.370Z","dateUpdated":"2026-06-24T07:14:28.622Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-24 08:16:24","lastModifiedDate":"2026-06-24 08:16:24","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"52939","Ordinal":"1","Title":"net/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked a","CVE":"CVE-2026-52939","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"52939","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked atomic completion\n\nrds_ib_xmit_atomic() always programs a masked atomic opcode\n(IB_WR_MASKED_ATOMIC_CMP_AND_SWP or IB_WR_MASKED_ATOMIC_FETCH_AND_ADD)\nfor every RDS atomic cmsg.  But the completion-side switch in\nrds_ib_send_unmap_op() only handles the non-masked opcodes, so a masked\natomic completion falls through to default and returns rm == NULL while\nsend->s_op is left set.  rds_ib_send_cqe_handler() then dereferences the\nNULL rm via rm->m_final_op, oopsing in softirq context.  An unprivileged\nAF_RDS sendmsg() of an atomic cmsg over an active RDS/IB connection\ntriggers it; on hardware that natively accepts masked atomics (mlx4,\nmlx5) no extra setup is needed.\n\n  RDS/IB: rds_ib_send_unmap_op: unexpected opcode 0xd in WR!\n  Oops: general protection fault [#1] SMP KASAN\n  KASAN: null-ptr-deref in range [0x0000000000000190-0x0000000000000197]\n  RIP: rds_ib_send_cqe_handler+0x25c/0xb10 (net/rds/ib_send.c:282)\n  Call Trace:\n   <IRQ>\n   rds_ib_send_cqe_handler (net/rds/ib_send.c:282)\n   poll_scq (net/rds/ib_cm.c:274)\n   rds_ib_tasklet_fn_send (net/rds/ib_cm.c:294)\n   tasklet_action_common (kernel/softirq.c:943)\n   handle_softirqs (kernel/softirq.c:573)\n   run_ksoftirqd (kernel/softirq.c:479)\n   </IRQ>\n  Kernel panic - not syncing: Fatal exception in interrupt\n\nHandle the masked atomic opcodes in the same case as the non-masked\nones: they map to the same struct rds_message.atomic union member, so\nthe existing container_of()/rds_ib_send_unmap_atomic() body is correct\nfor them.","Type":"Description","Title":"net/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked a"}]}}}