{"dataType": "CVE_RECORD", "dataVersion": "5.1", "cveMetadata": {"cveId": "CVE-2024-49868", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T12:17:06.019Z", "datePublished": "2024-10-21T18:01:10.722Z", "dateUpdated": "2025-05-04T09:39:56.588Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2025-05-04T09:39:56.588Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix a NULL pointer dereference when failed to start a new trasacntion\n\n[BUG]\nSyzbot reported a NULL pointer dereference with the following crash:\n\n FAULT_INJECTION: forcing a failure.\n start_transaction+0x830/0x1670 fs/btrfs/transaction.c:676\n prepare_to_relocate+0x31f/0x4c0 fs/btrfs/relocation.c:3642\n relocate_block_group+0x169/0xd20 fs/btrfs/relocation.c:3678\n ...\n BTRFS info (device loop0): balance: ended with status: -12\n Oops: general protection fault, probably for non-canonical address 0xdffffc00000000cc: 0000 [#1] PREEMPT SMP KASAN NOPTI\n KASAN: null-ptr-deref in range [0x0000000000000660-0x0000000000000667]\n RIP: 0010:btrfs_update_reloc_root+0x362/0xa80 fs/btrfs/relocation.c:926\n Call Trace:\n <TASK>\n commit_fs_roots+0x2ee/0x720 fs/btrfs/transaction.c:1496\n btrfs_commit_transaction+0xfaf/0x3740 fs/btrfs/transaction.c:2430\n del_balance_item fs/btrfs/volumes.c:3678 [inline]\n reset_balance_state+0x25e/0x3c0 fs/btrfs/volumes.c:3742\n btrfs_balance+0xead/0x10c0 fs/btrfs/volumes.c:4574\n btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3673\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:907 [inline]\n __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\n[CAUSE]\nThe allocation failure happens at the start_transaction() inside\nprepare_to_relocate(), and during the error handling we call\nunset_reloc_control(), which makes fs_info->balance_ctl to be NULL.\n\nThen we continue the error path cleanup in btrfs_balance() by calling\nreset_balance_state() which will call del_balance_item() to fully delete\nthe balance item in the root tree.\n\nHowever during the small window between set_reloc_contrl() and\nunset_reloc_control(), we can have a subvolume tree update and created a\nreloc_root for that subvolume.\n\nThen we go into the final btrfs_commit_transaction() of\ndel_balance_item(), and into btrfs_update_reloc_root() inside\ncommit_fs_roots().\n\nThat function checks if fs_info->reloc_ctl is in the merge_reloc_tree\nstage, but since fs_info->reloc_ctl is NULL, it results a NULL pointer\ndereference.\n\n[FIX]\nJust add extra check on fs_info->reloc_ctl inside\nbtrfs_update_reloc_root(), before checking\nfs_info->reloc_ctl->merge_reloc_tree.\n\nThat DEAD_RELOC_TREE handling is to prevent further modification to the\nreloc tree during merge stage, but since there is no reloc_ctl at all,\nwe do not need to bother that."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/btrfs/relocation.c"], "versions": [{"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "1282f001cbf56e5dd6e90a18e205a566793f4be0", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "d73d48acf36f57362df7e4f9d76568168bf5e944", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "37fee9c220b92c3b7bf22b51c51dde5364e7590b", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "d13249c0df7aab885acb149695f82c54c0822a70", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "7ad0c5868f2f0418619089513d95230c66cb7eb4", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "dc02c1440705e3451abd1c2c8114a5c1bb188e9f", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "39356ec0e319ed07627b3a0f402d0608546509e6", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "c3b47f49e83197e8dffd023ec568403bcdbb774b", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/btrfs/relocation.c"], "versions": [{"version": "5.4.285", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.227", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.168", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.113", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.55", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.10.14", "lessThanOrEqual": "6.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.11.3", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12", "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:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.4.285"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.10.227"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.15.168"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.1.113"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.6.55"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.10.14"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.11.3"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.12"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/1282f001cbf56e5dd6e90a18e205a566793f4be0"}, {"url": "https://git.kernel.org/stable/c/d73d48acf36f57362df7e4f9d76568168bf5e944"}, {"url": "https://git.kernel.org/stable/c/37fee9c220b92c3b7bf22b51c51dde5364e7590b"}, {"url": "https://git.kernel.org/stable/c/d13249c0df7aab885acb149695f82c54c0822a70"}, {"url": "https://git.kernel.org/stable/c/7ad0c5868f2f0418619089513d95230c66cb7eb4"}, {"url": "https://git.kernel.org/stable/c/dc02c1440705e3451abd1c2c8114a5c1bb188e9f"}, {"url": "https://git.kernel.org/stable/c/39356ec0e319ed07627b3a0f402d0608546509e6"}, {"url": "https://git.kernel.org/stable/c/c3b47f49e83197e8dffd023ec568403bcdbb774b"}], "title": "btrfs: fix a NULL pointer dereference when failed to start a new trasacntion", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2024-49868", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2024-10-22T13:47:20.255256Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-10-22T13:48:52.367Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2024-49868", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2024-10-22T13:47:20.255256Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-10-22T13:47:23.940Z"}}], "cna": {"title": "btrfs: fix a NULL pointer dereference when failed to start a new trasacntion", "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "1282f001cbf56e5dd6e90a18e205a566793f4be0", "versionType": "git"}, {"status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "d73d48acf36f57362df7e4f9d76568168bf5e944", "versionType": "git"}, {"status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "37fee9c220b92c3b7bf22b51c51dde5364e7590b", "versionType": "git"}, {"status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "d13249c0df7aab885acb149695f82c54c0822a70", "versionType": "git"}, {"status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "7ad0c5868f2f0418619089513d95230c66cb7eb4", "versionType": "git"}, {"status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "dc02c1440705e3451abd1c2c8114a5c1bb188e9f", "versionType": "git"}, {"status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "39356ec0e319ed07627b3a0f402d0608546509e6", "versionType": "git"}, {"status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "c3b47f49e83197e8dffd023ec568403bcdbb774b", "versionType": "git"}], "programFiles": ["fs/btrfs/relocation.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "unaffected", "version": "5.4.285", "versionType": "semver", "lessThanOrEqual": "5.4.*"}, {"status": "unaffected", "version": "5.10.227", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.168", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.113", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.55", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.10.14", "versionType": "semver", "lessThanOrEqual": "6.10.*"}, {"status": "unaffected", "version": "6.11.3", "versionType": "semver", "lessThanOrEqual": "6.11.*"}, {"status": "unaffected", "version": "6.12", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["fs/btrfs/relocation.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/1282f001cbf56e5dd6e90a18e205a566793f4be0"}, {"url": "https://git.kernel.org/stable/c/d73d48acf36f57362df7e4f9d76568168bf5e944"}, {"url": "https://git.kernel.org/stable/c/37fee9c220b92c3b7bf22b51c51dde5364e7590b"}, {"url": "https://git.kernel.org/stable/c/d13249c0df7aab885acb149695f82c54c0822a70"}, {"url": "https://git.kernel.org/stable/c/7ad0c5868f2f0418619089513d95230c66cb7eb4"}, {"url": "https://git.kernel.org/stable/c/dc02c1440705e3451abd1c2c8114a5c1bb188e9f"}, {"url": "https://git.kernel.org/stable/c/39356ec0e319ed07627b3a0f402d0608546509e6"}, {"url": "https://git.kernel.org/stable/c/c3b47f49e83197e8dffd023ec568403bcdbb774b"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix a NULL pointer dereference when failed to start a new trasacntion\n\n[BUG]\nSyzbot reported a NULL pointer dereference with the following crash:\n\n FAULT_INJECTION: forcing a failure.\n start_transaction+0x830/0x1670 fs/btrfs/transaction.c:676\n prepare_to_relocate+0x31f/0x4c0 fs/btrfs/relocation.c:3642\n relocate_block_group+0x169/0xd20 fs/btrfs/relocation.c:3678\n ...\n BTRFS info (device loop0): balance: ended with status: -12\n Oops: general protection fault, probably for non-canonical address 0xdffffc00000000cc: 0000 [#1] PREEMPT SMP KASAN NOPTI\n KASAN: null-ptr-deref in range [0x0000000000000660-0x0000000000000667]\n RIP: 0010:btrfs_update_reloc_root+0x362/0xa80 fs/btrfs/relocation.c:926\n Call Trace:\n <TASK>\n commit_fs_roots+0x2ee/0x720 fs/btrfs/transaction.c:1496\n btrfs_commit_transaction+0xfaf/0x3740 fs/btrfs/transaction.c:2430\n del_balance_item fs/btrfs/volumes.c:3678 [inline]\n reset_balance_state+0x25e/0x3c0 fs/btrfs/volumes.c:3742\n btrfs_balance+0xead/0x10c0 fs/btrfs/volumes.c:4574\n btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3673\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:907 [inline]\n __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\n[CAUSE]\nThe allocation failure happens at the start_transaction() inside\nprepare_to_relocate(), and during the error handling we call\nunset_reloc_control(), which makes fs_info->balance_ctl to be NULL.\n\nThen we continue the error path cleanup in btrfs_balance() by calling\nreset_balance_state() which will call del_balance_item() to fully delete\nthe balance item in the root tree.\n\nHowever during the small window between set_reloc_contrl() and\nunset_reloc_control(), we can have a subvolume tree update and created a\nreloc_root for that subvolume.\n\nThen we go into the final btrfs_commit_transaction() of\ndel_balance_item(), and into btrfs_update_reloc_root() inside\ncommit_fs_roots().\n\nThat function checks if fs_info->reloc_ctl is in the merge_reloc_tree\nstage, but since fs_info->reloc_ctl is NULL, it results a NULL pointer\ndereference.\n\n[FIX]\nJust add extra check on fs_info->reloc_ctl inside\nbtrfs_update_reloc_root(), before checking\nfs_info->reloc_ctl->merge_reloc_tree.\n\nThat DEAD_RELOC_TREE handling is to prevent further modification to the\nreloc tree during merge stage, but since there is no reloc_ctl at all,\nwe do not need to bother that."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.4.285"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.227"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.168"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.113"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.55"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.10.14"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.11.3"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2025-05-04T09:39:56.588Z"}}}, "cveMetadata": {"cveId": "CVE-2024-49868", "state": "PUBLISHED", "dateUpdated": "2025-05-04T09:39:56.588Z", "dateReserved": "2024-10-21T12:17:06.019Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2024-10-21T18:01:10.722Z", "assignerShortName": "Linux"}, "dataVersion": "5.1"}

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Informaci\u00f3n de BTRFS (dispositivo loop0): balance: finalizado con estado: -12 Vaya: error de protecci\u00f3n general, probablemente para la direcci\u00f3n no can\u00f3nica 0xdffffc00000000cc: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref en el rango [0x000000000000660-0x0000000000000667] RIP: 0010:btrfs_update_reloc_root+0x362/0xa80 fs/btrfs/relocation.c:926 Seguimiento de llamadas: commit_fs_roots+0x2ee/0x720 fs/btrfs/transaction.c:1496 btrfs_commit_transaction+0xfaf/0x3740 fs/btrfs/transaction.c:2430 del_balance_item fs/btrfs/volumes.c:3678 [en l\u00ednea] reset_balance_state+0x25e/0x3c0 fs/btrfs/volumes.c:3742 btrfs_balance+0xead/0x10c0 fs/btrfs/volumes.c:4574 btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3673 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f [CAUSA] El fallo de asignaci\u00f3n ocurre en start_transaction() dentro de prepare_to_relocate(), y durante el manejo de errores llamamos a unset_reloc_control(), lo que hace que fs_info-&gt;balance_ctl sea NULL. Luego continuamos con la limpieza de la ruta de error en btrfs_balance() llamando a reset_balance_state() que llamar\u00e1 a del_balance_item() para eliminar por completo el elemento de balance en el \u00e1rbol ra\u00edz. Sin embargo, durante la peque\u00f1a ventana entre set_reloc_contrl() y unset_reloc_control(), podemos tener una actualizaci\u00f3n del \u00e1rbol de subvolumen y crear un reloc_root para ese subvolumen. Luego pasamos a la btrfs_commit_transaction() final de del_balance_item() y a btrfs_update_reloc_root() dentro de commit_fs_roots(). Esa funci\u00f3n verifica si fs_info-&gt;reloc_ctl est\u00e1 en la etapa merge_reloc_tree, pero dado que fs_info-&gt;reloc_ctl es NULL, da como resultado una desreferencia de puntero NULL. [SOLUCI\u00d3N] Solo hay que a\u00f1adir una comprobaci\u00f3n adicional en fs_info-&gt;reloc_ctl dentro de btrfs_update_reloc_root(), antes de comprobar fs_info-&gt;reloc_ctl-&gt;merge_reloc_tree. El manejo de DEAD_RELOC_TREE sirve para evitar modificaciones adicionales del \u00e1rbol de reubicaci\u00f3n durante la etapa de fusi\u00f3n, pero como no hay ning\u00fan reloc_ctl, no tenemos que preocuparnos por eso."}], "id": "CVE-2024-49868", "lastModified": "2024-11-08T16:15:29.227", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2024-10-21T18:15:06.623", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1282f001cbf56e5dd6e90a18e205a566793f4be0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/37fee9c220b92c3b7bf22b51c51dde5364e7590b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/39356ec0e319ed07627b3a0f402d0608546509e6"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/7ad0c5868f2f0418619089513d95230c66cb7eb4"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c3b47f49e83197e8dffd023ec568403bcdbb774b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/d13249c0df7aab885acb149695f82c54c0822a70"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/d73d48acf36f57362df7e4f9d76568168bf5e944"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/dc02c1440705e3451abd1c2c8114a5c1bb188e9f"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-476"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: btrfs: fix a NULL pointer dereference when failed to start a new trasacntion", "id": "2320483", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2320483"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-476", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nbtrfs: fix a NULL pointer dereference when failed to start a new trasacntion\n[BUG]\nSyzbot reported a NULL pointer dereference with the following crash:\nFAULT_INJECTION: forcing a failure.\nstart_transaction+0x830/0x1670 fs/btrfs/transaction.c:676\nprepare_to_relocate+0x31f/0x4c0 fs/btrfs/relocation.c:3642\nrelocate_block_group+0x169/0xd20 fs/btrfs/relocation.c:3678\n...\nBTRFS info (device loop0): balance: ended with status: -12\nOops: general protection fault, probably for non-canonical address 0xdffffc00000000cc: 0000 [#1] PREEMPT SMP KASAN NOPTI\nKASAN: null-ptr-deref in range [0x0000000000000660-0x0000000000000667]\nRIP: 0010:btrfs_update_reloc_root+0x362/0xa80 fs/btrfs/relocation.c:926\nCall Trace:\n<TASK>\ncommit_fs_roots+0x2ee/0x720 fs/btrfs/transaction.c:1496\nbtrfs_commit_transaction+0xfaf/0x3740 fs/btrfs/transaction.c:2430\ndel_balance_item fs/btrfs/volumes.c:3678 [inline]\nreset_balance_state+0x25e/0x3c0 fs/btrfs/volumes.c:3742\nbtrfs_balance+0xead/0x10c0 fs/btrfs/volumes.c:4574\nbtrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3673\nvfs_ioctl fs/ioctl.c:51 [inline]\n__do_sys_ioctl fs/ioctl.c:907 [inline]\n__se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893\ndo_syscall_x64 arch/x86/entry/common.c:52 [inline]\ndo_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\nentry_SYSCALL_64_after_hwframe+0x77/0x7f\n[CAUSE]\nThe allocation failure happens at the start_transaction() inside\nprepare_to_relocate(), and during the error handling we call\nunset_reloc_control(), which makes fs_info->balance_ctl to be NULL.\nThen we continue the error path cleanup in btrfs_balance() by calling\nreset_balance_state() which will call del_balance_item() to fully delete\nthe balance item in the root tree.\nHowever during the small window between set_reloc_contrl() and\nunset_reloc_control(), we can have a subvolume tree update and created a\nreloc_root for that subvolume.\nThen we go into the final btrfs_commit_transaction() of\ndel_balance_item(), and into btrfs_update_reloc_root() inside\ncommit_fs_roots().\nThat function checks if fs_info->reloc_ctl is in the merge_reloc_tree\nstage, but since fs_info->reloc_ctl is NULL, it results a NULL pointer\ndereference.\n[FIX]\nJust add extra check on fs_info->reloc_ctl inside\nbtrfs_update_reloc_root(), before checking\nfs_info->reloc_ctl->merge_reloc_tree.\nThat DEAD_RELOC_TREE handling is to prevent further modification to the\nreloc tree during merge stage, but since there is no reloc_ctl at all,\nwe do not need to bother that."], "name": "CVE-2024-49868", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-10-21T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2024-49868\nhttps://nvd.nist.gov/vuln/detail/CVE-2024-49868\nhttps://lore.kernel.org/linux-cve-announce/2024102113-CVE-2024-49868-8dce@gregkh/T"], "threat_severity": "Moderate"}

{}