{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2021-47375", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-05-21T14:58:30.811Z", "datePublished": "2024-05-21T15:03:39.090Z", "dateUpdated": "2026-05-11T13:53:29.691Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T13:53:29.691Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nblktrace: Fix uaf in blk_trace access after removing by sysfs\n\nThere is an use-after-free problem triggered by following process:\n\n P1(sda)\t\t\t\tP2(sdb)\n\t\t\techo 0 > /sys/block/sdb/trace/enable\n\t\t\t blk_trace_remove_queue\n\t\t\t synchronize_rcu\n\t\t\t blk_trace_free\n\t\t\t relay_close\nrcu_read_lock\n__blk_add_trace\n trace_note_tsk\n (Iterate running_trace_list)\n\t\t\t relay_close_buf\n\t\t\t\t relay_destroy_buf\n\t\t\t\t kfree(buf)\n trace_note(sdb's bt)\n relay_reserve\n buf->offset <- nullptr deference (use-after-free) !!!\nrcu_read_unlock\n\n[ 502.714379] BUG: kernel NULL pointer dereference, address:\n0000000000000010\n[ 502.715260] #PF: supervisor read access in kernel mode\n[ 502.715903] #PF: error_code(0x0000) - not-present page\n[ 502.716546] PGD 103984067 P4D 103984067 PUD 17592b067 PMD 0\n[ 502.717252] Oops: 0000 [#1] SMP\n[ 502.720308] RIP: 0010:trace_note.isra.0+0x86/0x360\n[ 502.732872] Call Trace:\n[ 502.733193] __blk_add_trace.cold+0x137/0x1a3\n[ 502.733734] blk_add_trace_rq+0x7b/0xd0\n[ 502.734207] blk_add_trace_rq_issue+0x54/0xa0\n[ 502.734755] blk_mq_start_request+0xde/0x1b0\n[ 502.735287] scsi_queue_rq+0x528/0x1140\n...\n[ 502.742704] sg_new_write.isra.0+0x16e/0x3e0\n[ 502.747501] sg_ioctl+0x466/0x1100\n\nReproduce method:\n ioctl(/dev/sda, BLKTRACESETUP, blk_user_trace_setup[buf_size=127])\n ioctl(/dev/sda, BLKTRACESTART)\n ioctl(/dev/sdb, BLKTRACESETUP, blk_user_trace_setup[buf_size=127])\n ioctl(/dev/sdb, BLKTRACESTART)\n\n echo 0 > /sys/block/sdb/trace/enable &\n // Add delay(mdelay/msleep) before kernel enters blk_trace_free()\n\n ioctl$SG_IO(/dev/sda, SG_IO, ...)\n // Enters trace_note_tsk() after blk_trace_free() returned\n // Use mdelay in rcu region rather than msleep(which may schedule out)\n\nRemove blk_trace from running_list before calling blk_trace_free() by\nsysfs if blk_trace is at Blktrace_running state." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "kernel/trace/blktrace.c" ], "versions": [ { "version": "c71a896154119f4ca9e89d6078f5f63ad60ef199", "lessThan": "488da313edf3abea7f7733efe011c96b23740ab5", "status": "affected", "versionType": "git" }, { "version": "c71a896154119f4ca9e89d6078f5f63ad60ef199", "lessThan": "dacfd5e4d1142bfb3809aab3634a375f6f373269", "status": "affected", "versionType": "git" }, { "version": "c71a896154119f4ca9e89d6078f5f63ad60ef199", "lessThan": "d56171d9360c0170c5c5f8f7e2362a2e999eca40", "status": "affected", "versionType": "git" }, { "version": "c71a896154119f4ca9e89d6078f5f63ad60ef199", "lessThan": "677e362ba807f3aafe6f405c07e0b37244da5222", "status": "affected", "versionType": "git" }, { "version": "c71a896154119f4ca9e89d6078f5f63ad60ef199", "lessThan": "ebb8d26d93c3ec3c7576c52a8373a2309423c069", "status": "affected", "versionType": "git" }, { "version": "c71a896154119f4ca9e89d6078f5f63ad60ef199", "lessThan": "3815fe7371d2411ce164281cef40d9fc7b323dee", "status": "affected", "versionType": "git" }, { "version": "c71a896154119f4ca9e89d6078f5f63ad60ef199", "lessThan": "a5f8e86192612d0183047448d8bbe7918b3f1a26", "status": "affected", "versionType": "git" }, { "version": "c71a896154119f4ca9e89d6078f5f63ad60ef199", "lessThan": "5afedf670caf30a2b5a52da96eb7eac7dee6a9c9", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "kernel/trace/blktrace.c" ], "versions": [ { "version": "2.6.30", "status": "affected" }, { "version": "0", "lessThan": "2.6.30", "status": "unaffected", "versionType": "semver" }, { "version": "4.4.286", "lessThanOrEqual": "4.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "4.9.285", "lessThanOrEqual": "4.9.*", "status": "unaffected", "versionType": "semver" }, { "version": "4.14.249", "lessThanOrEqual": "4.14.*", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.209", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.150", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.70", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.14.9", "lessThanOrEqual": "5.14.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "4.4.286" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "4.9.285" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "4.14.249" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "4.19.209" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.4.150" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.10.70" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.14.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.15" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/488da313edf3abea7f7733efe011c96b23740ab5" }, { "url": "https://git.kernel.org/stable/c/dacfd5e4d1142bfb3809aab3634a375f6f373269" }, { "url": "https://git.kernel.org/stable/c/d56171d9360c0170c5c5f8f7e2362a2e999eca40" }, { "url": "https://git.kernel.org/stable/c/677e362ba807f3aafe6f405c07e0b37244da5222" }, { "url": "https://git.kernel.org/stable/c/ebb8d26d93c3ec3c7576c52a8373a2309423c069" }, { "url": "https://git.kernel.org/stable/c/3815fe7371d2411ce164281cef40d9fc7b323dee" }, { "url": "https://git.kernel.org/stable/c/a5f8e86192612d0183047448d8bbe7918b3f1a26" }, { "url": "https://git.kernel.org/stable/c/5afedf670caf30a2b5a52da96eb7eac7dee6a9c9" } ], "title": "blktrace: Fix uaf in blk_trace access after removing by sysfs", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "problemTypes": [ { "descriptions": [ { "type": "CWE", "cweId": "CWE-416", "lang": "en", "description": "CWE-416 Use After Free" } ] } ], "metrics": [ { "cvssV3_1": { "scope": "UNCHANGED", "version": "3.1", "baseScore": 6.2, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH" } }, { "other": { "type": "ssvc", "content": { "timestamp": "2024-06-17T17:37:23.607827Z", "id": "CVE-2021-47375", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-10-27T13:59:18.148Z" } }, { "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:32:08.654Z" }, "title": "CVE Program Container", "references": [ { "url": "https://git.kernel.org/stable/c/488da313edf3abea7f7733efe011c96b23740ab5", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/dacfd5e4d1142bfb3809aab3634a375f6f373269", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/d56171d9360c0170c5c5f8f7e2362a2e999eca40", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/677e362ba807f3aafe6f405c07e0b37244da5222", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/ebb8d26d93c3ec3c7576c52a8373a2309423c069", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/3815fe7371d2411ce164281cef40d9fc7b323dee", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/a5f8e86192612d0183047448d8bbe7918b3f1a26", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/5afedf670caf30a2b5a52da96eb7eac7dee6a9c9", "tags": [ "x_transferred" ] } ] } ] } }