{"api_version":"1","generated_at":"2026-05-01T21:59:34+00:00","cve":"CVE-2026-43054","urls":{"html":"https://cve.report/CVE-2026-43054","api":"https://cve.report/api/cve/CVE-2026-43054.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43054","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43054"},"summary":{"title":"scsi: target: tcm_loop: Drain commands in target_reset handler","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: target: tcm_loop: Drain commands in target_reset handler\n\ntcm_loop_target_reset() violates the SCSI EH contract: it returns SUCCESS\nwithout draining any in-flight commands.  The SCSI EH documentation\n(scsi_eh.rst) requires that when a reset handler returns SUCCESS the driver\nhas made lower layers \"forget about timed out scmds\" and is ready for new\ncommands.  Every other SCSI LLD (virtio_scsi, mpt3sas, ipr, scsi_debug,\nmpi3mr) enforces this by draining or completing outstanding commands before\nreturning SUCCESS.\n\nBecause tcm_loop_target_reset() doesn't drain, the SCSI EH reuses in-flight\nscsi_cmnd structures for recovery commands (e.g. TUR) while the target core\nstill has async completion work queued for the old se_cmd.  The memset in\nqueuecommand zeroes se_lun and lun_ref_active, causing\ntransport_lun_remove_cmd() to skip its percpu_ref_put().  The leaked LUN\nreference prevents transport_clear_lun_ref() from completing, hanging\nconfigfs LUN unlink forever in D-state:\n\n  INFO: task rm:264 blocked for more than 122 seconds.\n  rm              D    0   264    258 0x00004000\n  Call Trace:\n   __schedule+0x3d0/0x8e0\n   schedule+0x36/0xf0\n   transport_clear_lun_ref+0x78/0x90 [target_core_mod]\n   core_tpg_remove_lun+0x28/0xb0 [target_core_mod]\n   target_fabric_port_unlink+0x50/0x60 [target_core_mod]\n   configfs_unlink+0x156/0x1f0 [configfs]\n   vfs_unlink+0x109/0x290\n   do_unlinkat+0x1d5/0x2d0\n\nFix this by making tcm_loop_target_reset() actually drain commands:\n\n 1. Issue TMR_LUN_RESET via tcm_loop_issue_tmr() to drain all commands that\n    the target core knows about (those not yet CMD_T_COMPLETE).\n\n 2. Use blk_mq_tagset_busy_iter() to iterate all started requests and\n    flush_work() on each se_cmd — this drains any deferred completion work\n    for commands that already had CMD_T_COMPLETE set before the TMR (which\n    the TMR skips via __target_check_io_state()).  This is the same pattern\n    used by mpi3mr, scsi_debug, and libsas to drain outstanding commands\n    during reset.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-01 15:16:51","updated_at":"2026-05-01 15:24:14"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/1333eee56cdf3f0cf67c6ab4114c2c9e0a952026","name":"https://git.kernel.org/stable/c/1333eee56cdf3f0cf67c6ab4114c2c9e0a952026","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/05ac3754467363558a0a54ae4bb7c89b2c9574cf","name":"https://git.kernel.org/stable/c/05ac3754467363558a0a54ae4bb7c89b2c9574cf","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/15f5241d5a52364a7e7867b49128b0442dbcad9d","name":"https://git.kernel.org/stable/c/15f5241d5a52364a7e7867b49128b0442dbcad9d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/7cbd69aaa507b1245240a28022bf5da0f07c68d9","name":"https://git.kernel.org/stable/c/7cbd69aaa507b1245240a28022bf5da0f07c68d9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a836054ea81014117ec6b73529a21626a9e1f829","name":"https://git.kernel.org/stable/c/a836054ea81014117ec6b73529a21626a9e1f829","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/103f79e4949513247d763c6e7f3cbbf62017afdf","name":"https://git.kernel.org/stable/c/103f79e4949513247d763c6e7f3cbbf62017afdf","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/757c43c692294cdfad31390accc0e90429b2ef8a","name":"https://git.kernel.org/stable/c/757c43c692294cdfad31390accc0e90429b2ef8a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-43054","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43054","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3 757c43c692294cdfad31390accc0e90429b2ef8a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3 103f79e4949513247d763c6e7f3cbbf62017afdf git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3 15f5241d5a52364a7e7867b49128b0442dbcad9d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3 7cbd69aaa507b1245240a28022bf5da0f07c68d9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3 a836054ea81014117ec6b73529a21626a9e1f829 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3 05ac3754467363558a0a54ae4bb7c89b2c9574cf git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3 1333eee56cdf3f0cf67c6ab4114c2c9e0a952026 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.13","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.13 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.203 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.168 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.134 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.81 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.22 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.12 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * 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":["drivers/target/loopback/tcm_loop.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"757c43c692294cdfad31390accc0e90429b2ef8a","status":"affected","version":"e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3","versionType":"git"},{"lessThan":"103f79e4949513247d763c6e7f3cbbf62017afdf","status":"affected","version":"e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3","versionType":"git"},{"lessThan":"15f5241d5a52364a7e7867b49128b0442dbcad9d","status":"affected","version":"e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3","versionType":"git"},{"lessThan":"7cbd69aaa507b1245240a28022bf5da0f07c68d9","status":"affected","version":"e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3","versionType":"git"},{"lessThan":"a836054ea81014117ec6b73529a21626a9e1f829","status":"affected","version":"e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3","versionType":"git"},{"lessThan":"05ac3754467363558a0a54ae4bb7c89b2c9574cf","status":"affected","version":"e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3","versionType":"git"},{"lessThan":"1333eee56cdf3f0cf67c6ab4114c2c9e0a952026","status":"affected","version":"e0eb5d38b732b011cd9ed5b1bf9f59b83c2500d3","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/target/loopback/tcm_loop.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.13"},{"lessThan":"5.13","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.203","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.168","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.134","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.81","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.22","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.12","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.203","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.168","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.134","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.81","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.22","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.12","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"5.13","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: target: tcm_loop: Drain commands in target_reset handler\n\ntcm_loop_target_reset() violates the SCSI EH contract: it returns SUCCESS\nwithout draining any in-flight commands.  The SCSI EH documentation\n(scsi_eh.rst) requires that when a reset handler returns SUCCESS the driver\nhas made lower layers \"forget about timed out scmds\" and is ready for new\ncommands.  Every other SCSI LLD (virtio_scsi, mpt3sas, ipr, scsi_debug,\nmpi3mr) enforces this by draining or completing outstanding commands before\nreturning SUCCESS.\n\nBecause tcm_loop_target_reset() doesn't drain, the SCSI EH reuses in-flight\nscsi_cmnd structures for recovery commands (e.g. TUR) while the target core\nstill has async completion work queued for the old se_cmd.  The memset in\nqueuecommand zeroes se_lun and lun_ref_active, causing\ntransport_lun_remove_cmd() to skip its percpu_ref_put().  The leaked LUN\nreference prevents transport_clear_lun_ref() from completing, hanging\nconfigfs LUN unlink forever in D-state:\n\n  INFO: task rm:264 blocked for more than 122 seconds.\n  rm              D    0   264    258 0x00004000\n  Call Trace:\n   __schedule+0x3d0/0x8e0\n   schedule+0x36/0xf0\n   transport_clear_lun_ref+0x78/0x90 [target_core_mod]\n   core_tpg_remove_lun+0x28/0xb0 [target_core_mod]\n   target_fabric_port_unlink+0x50/0x60 [target_core_mod]\n   configfs_unlink+0x156/0x1f0 [configfs]\n   vfs_unlink+0x109/0x290\n   do_unlinkat+0x1d5/0x2d0\n\nFix this by making tcm_loop_target_reset() actually drain commands:\n\n 1. Issue TMR_LUN_RESET via tcm_loop_issue_tmr() to drain all commands that\n    the target core knows about (those not yet CMD_T_COMPLETE).\n\n 2. Use blk_mq_tagset_busy_iter() to iterate all started requests and\n    flush_work() on each se_cmd — this drains any deferred completion work\n    for commands that already had CMD_T_COMPLETE set before the TMR (which\n    the TMR skips via __target_check_io_state()).  This is the same pattern\n    used by mpi3mr, scsi_debug, and libsas to drain outstanding commands\n    during reset."}],"providerMetadata":{"dateUpdated":"2026-05-01T14:15:47.396Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/757c43c692294cdfad31390accc0e90429b2ef8a"},{"url":"https://git.kernel.org/stable/c/103f79e4949513247d763c6e7f3cbbf62017afdf"},{"url":"https://git.kernel.org/stable/c/15f5241d5a52364a7e7867b49128b0442dbcad9d"},{"url":"https://git.kernel.org/stable/c/7cbd69aaa507b1245240a28022bf5da0f07c68d9"},{"url":"https://git.kernel.org/stable/c/a836054ea81014117ec6b73529a21626a9e1f829"},{"url":"https://git.kernel.org/stable/c/05ac3754467363558a0a54ae4bb7c89b2c9574cf"},{"url":"https://git.kernel.org/stable/c/1333eee56cdf3f0cf67c6ab4114c2c9e0a952026"}],"title":"scsi: target: tcm_loop: Drain commands in target_reset handler","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43054","datePublished":"2026-05-01T14:15:47.396Z","dateReserved":"2026-05-01T14:12:55.980Z","dateUpdated":"2026-05-01T14:15:47.396Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-01 15:16:51","lastModifiedDate":"2026-05-01 15:24:14","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43054","Ordinal":"1","Title":"scsi: target: tcm_loop: Drain commands in target_reset handler","CVE":"CVE-2026-43054","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43054","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: target: tcm_loop: Drain commands in target_reset handler\n\ntcm_loop_target_reset() violates the SCSI EH contract: it returns SUCCESS\nwithout draining any in-flight commands.  The SCSI EH documentation\n(scsi_eh.rst) requires that when a reset handler returns SUCCESS the driver\nhas made lower layers \"forget about timed out scmds\" and is ready for new\ncommands.  Every other SCSI LLD (virtio_scsi, mpt3sas, ipr, scsi_debug,\nmpi3mr) enforces this by draining or completing outstanding commands before\nreturning SUCCESS.\n\nBecause tcm_loop_target_reset() doesn't drain, the SCSI EH reuses in-flight\nscsi_cmnd structures for recovery commands (e.g. TUR) while the target core\nstill has async completion work queued for the old se_cmd.  The memset in\nqueuecommand zeroes se_lun and lun_ref_active, causing\ntransport_lun_remove_cmd() to skip its percpu_ref_put().  The leaked LUN\nreference prevents transport_clear_lun_ref() from completing, hanging\nconfigfs LUN unlink forever in D-state:\n\n  INFO: task rm:264 blocked for more than 122 seconds.\n  rm              D    0   264    258 0x00004000\n  Call Trace:\n   __schedule+0x3d0/0x8e0\n   schedule+0x36/0xf0\n   transport_clear_lun_ref+0x78/0x90 [target_core_mod]\n   core_tpg_remove_lun+0x28/0xb0 [target_core_mod]\n   target_fabric_port_unlink+0x50/0x60 [target_core_mod]\n   configfs_unlink+0x156/0x1f0 [configfs]\n   vfs_unlink+0x109/0x290\n   do_unlinkat+0x1d5/0x2d0\n\nFix this by making tcm_loop_target_reset() actually drain commands:\n\n 1. Issue TMR_LUN_RESET via tcm_loop_issue_tmr() to drain all commands that\n    the target core knows about (those not yet CMD_T_COMPLETE).\n\n 2. Use blk_mq_tagset_busy_iter() to iterate all started requests and\n    flush_work() on each se_cmd — this drains any deferred completion work\n    for commands that already had CMD_T_COMPLETE set before the TMR (which\n    the TMR skips via __target_check_io_state()).  This is the same pattern\n    used by mpi3mr, scsi_debug, and libsas to drain outstanding commands\n    during reset.","Type":"Description","Title":"scsi: target: tcm_loop: Drain commands in target_reset handler"}]}}}