fkie_cve-2024-49882
Vulnerability from fkie_nvd
Published
2024-10-21 18:15
Modified
2024-11-08 16:15
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix double brelse() the buffer of the extents path
In ext4_ext_try_to_merge_up(), set path[1].p_bh to NULL after it has been
released, otherwise it may be released twice. An example of what triggers
this is as follows:
split2 map split1
|--------|-------|--------|
ext4_ext_map_blocks
ext4_ext_handle_unwritten_extents
ext4_split_convert_extents
// path->p_depth == 0
ext4_split_extent
// 1. do split1
ext4_split_extent_at
|ext4_ext_insert_extent
| ext4_ext_create_new_leaf
| ext4_ext_grow_indepth
| le16_add_cpu(&neh->eh_depth, 1)
| ext4_find_extent
| // return -ENOMEM
|// get error and try zeroout
|path = ext4_find_extent
| path->p_depth = 1
|ext4_ext_try_to_merge
| ext4_ext_try_to_merge_up
| path->p_depth = 0
| brelse(path[1].p_bh) ---> not set to NULL here
|// zeroout success
// 2. update path
ext4_find_extent
// 3. do split2
ext4_split_extent_at
ext4_ext_insert_extent
ext4_ext_create_new_leaf
ext4_ext_grow_indepth
le16_add_cpu(&neh->eh_depth, 1)
ext4_find_extent
path[0].p_bh = NULL;
path->p_depth = 1
read_extent_tree_block ---> return err
// path[1].p_bh is still the old value
ext4_free_ext_path
ext4_ext_drop_refs
// path->p_depth == 1
brelse(path[1].p_bh) ---> brelse a buffer twice
Finally got the following WARRNING when removing the buffer from lru:
============================================
VFS: brelse: Trying to free free buffer
WARNING: CPU: 2 PID: 72 at fs/buffer.c:1241 __brelse+0x58/0x90
CPU: 2 PID: 72 Comm: kworker/u19:1 Not tainted 6.9.0-dirty #716
RIP: 0010:__brelse+0x58/0x90
Call Trace:
<TASK>
__find_get_block+0x6e7/0x810
bdev_getblk+0x2b/0x480
__ext4_get_inode_loc+0x48a/0x1240
ext4_get_inode_loc+0xb2/0x150
ext4_reserve_inode_write+0xb7/0x230
__ext4_mark_inode_dirty+0x144/0x6a0
ext4_ext_insert_extent+0x9c8/0x3230
ext4_ext_map_blocks+0xf45/0x2dc0
ext4_map_blocks+0x724/0x1700
ext4_do_writepages+0x12d6/0x2a70
[...]
============================================
References
Impacted products
Vendor | Product | Version | |
---|---|---|---|
linux | linux_kernel | * | |
linux | linux_kernel | * | |
linux | linux_kernel | * | |
linux | linux_kernel | * | |
linux | linux_kernel | * | |
linux | linux_kernel | * |
{ "configurations": [ { "nodes": [ { "cpeMatch": [ { "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "3B73A13A-D7BE-4035-BEF2-2821D9D5CB6D", "versionEndExcluding": "5.10.227", "versionStartIncluding": "3.7", "vulnerable": true }, { "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "4D51C05D-455B-4D8D-89E7-A58E140B864C", "versionEndExcluding": "5.15.168", "versionStartIncluding": "5.11", "vulnerable": true }, { "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "D01BD22E-ACD1-4618-9D01-6116570BE1EE", "versionEndExcluding": "6.1.113", "versionStartIncluding": "5.16", "vulnerable": true }, { "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "E90B9576-56C4-47BC-AAB0-C5B2D438F5D0", "versionEndExcluding": "6.6.55", "versionStartIncluding": "6.2", "vulnerable": true }, { "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "4C16BCE0-FFA0-4599-BE0A-1FD65101C021", "versionEndExcluding": "6.10.14", "versionStartIncluding": "6.7", "vulnerable": true }, { "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "54D9C704-D679-41A7-9C40-10A6B1E7FFE9", "versionEndExcluding": "6.11.3", "versionStartIncluding": "6.11", "vulnerable": true } ], "negate": false, "operator": "OR" } ] } ], "cveTags": [], "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix double brelse() the buffer of the extents path\n\nIn ext4_ext_try_to_merge_up(), set path[1].p_bh to NULL after it has been\nreleased, otherwise it may be released twice. An example of what triggers\nthis is as follows:\n\n split2 map split1\n|--------|-------|--------|\n\next4_ext_map_blocks\n ext4_ext_handle_unwritten_extents\n ext4_split_convert_extents\n // path-\u003ep_depth == 0\n ext4_split_extent\n // 1. do split1\n ext4_split_extent_at\n |ext4_ext_insert_extent\n | ext4_ext_create_new_leaf\n | ext4_ext_grow_indepth\n | le16_add_cpu(\u0026neh-\u003eeh_depth, 1)\n | ext4_find_extent\n | // return -ENOMEM\n |// get error and try zeroout\n |path = ext4_find_extent\n | path-\u003ep_depth = 1\n |ext4_ext_try_to_merge\n | ext4_ext_try_to_merge_up\n | path-\u003ep_depth = 0\n | brelse(path[1].p_bh) ---\u003e not set to NULL here\n |// zeroout success\n // 2. update path\n ext4_find_extent\n // 3. do split2\n ext4_split_extent_at\n ext4_ext_insert_extent\n ext4_ext_create_new_leaf\n ext4_ext_grow_indepth\n le16_add_cpu(\u0026neh-\u003eeh_depth, 1)\n ext4_find_extent\n path[0].p_bh = NULL;\n path-\u003ep_depth = 1\n read_extent_tree_block ---\u003e return err\n // path[1].p_bh is still the old value\n ext4_free_ext_path\n ext4_ext_drop_refs\n // path-\u003ep_depth == 1\n brelse(path[1].p_bh) ---\u003e brelse a buffer twice\n\nFinally got the following WARRNING when removing the buffer from lru:\n\n============================================\nVFS: brelse: Trying to free free buffer\nWARNING: CPU: 2 PID: 72 at fs/buffer.c:1241 __brelse+0x58/0x90\nCPU: 2 PID: 72 Comm: kworker/u19:1 Not tainted 6.9.0-dirty #716\nRIP: 0010:__brelse+0x58/0x90\nCall Trace:\n \u003cTASK\u003e\n __find_get_block+0x6e7/0x810\n bdev_getblk+0x2b/0x480\n __ext4_get_inode_loc+0x48a/0x1240\n ext4_get_inode_loc+0xb2/0x150\n ext4_reserve_inode_write+0xb7/0x230\n __ext4_mark_inode_dirty+0x144/0x6a0\n ext4_ext_insert_extent+0x9c8/0x3230\n ext4_ext_map_blocks+0xf45/0x2dc0\n ext4_map_blocks+0x724/0x1700\n ext4_do_writepages+0x12d6/0x2a70\n[...]\n============================================" }, { "lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: corregir el doble brelse() del b\u00fafer de la ruta de las extensiones En ext4_ext_try_to_merge_up(), establezca path[1].p_bh en NULL despu\u00e9s de que se haya liberado, de lo contrario, puede liberarse dos veces. Un ejemplo de lo que desencadena esto es el siguiente: split2 map split1 |--------|-------|--------| ext4_ext_map_blocks ext4_ext_handle_unwritten_extents ext4_split_convert_extents // path-\u0026gt;p_depth == 0 ext4_split_extent // 1. hacer split1 ext4_split_extent_at |ext4_ext_insert_extent | ext4_ext_create_new_leaf | ext4_ext_grow_indepth | le16_add_cpu(\u0026amp;neh-\u0026gt;eh_depth, 1) | ext4_find_extent | // devuelve -ENOMEM |// obtiene el error e intenta poner a cero |path = ext4_find_extent | path-\u0026gt;p_depth = 1 |ext4_ext_try_to_merge | ext4_ext_try_to_merge_up | path-\u0026gt;p_depth = 0 | brelse(path[1].p_bh) ---\u0026gt; no establecido en NULL aqu\u00ed |// puesta a cero exitosa // 2. actualizar ruta ext4_find_extent // 3. hacer split2 ext4_split_extent_at ext4_ext_insert_extent ext4_ext_create_new_leaf ext4_ext_grow_indepth le16_add_cpu(\u0026amp;neh-\u0026gt;eh_depth, 1) ext4_find_extent path[0].p_bh = NULL; path-\u0026gt;p_depth = 1 read_extent_tree_block ---\u0026gt; return err // path[1].p_bh sigue siendo el valor anterior ext4_free_ext_path ext4_ext_drop_refs // path-\u0026gt;p_depth == 1 brelse(path[1].p_bh) ---\u0026gt; brelse un buffer dos veces Finalmente obtuve la siguiente ADVERTENCIA al eliminar el buffer de lru: =============================================== VFS: brelse: Intentando liberar b\u00fafer libre ADVERTENCIA: CPU: 2 PID: 72 en fs/buffer.c:1241 __brelse+0x58/0x90 CPU: 2 PID: 72 Comm: kworker/u19:1 No contaminado 6.9.0-dirty #716 RIP: 0010:__brelse+0x58/0x90 Seguimiento de llamadas: __find_get_block+0x6e7/0x810 bdev_getblk+0x2b/0x480 __ext4_get_inode_loc+0x48a/0x1240 ext4_get_inode_loc+0xb2/0x150 ext4_reserve_inode_write+0xb7/0x230 __ext4_mark_inode_dirty+0x144/0x6a0 ext4_ext_insert_extent+0x9c8/0x3230 ext4_ext_map_blocks+0xf45/0x2dc0 ext4_map_blocks+0x724/0x1700 ext4_do_writepages+0x12d6/0x2a70 [...] ============================================" } ], "id": "CVE-2024-49882", "lastModified": "2024-11-08T16:15:30.123", "metrics": { "cvssMetricV31": [ { "cvssData": { "attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1" }, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary" } ] }, "published": "2024-10-21T18:15:10.790", "references": [ { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ], "url": "https://git.kernel.org/stable/c/230ee0535d01478bad9a3037292043f39b9be10b" }, { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ], "url": "https://git.kernel.org/stable/c/32bbb59e3f18facd7201bef110010bf35819b8c3" }, { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ], "url": "https://git.kernel.org/stable/c/68a69cf60660c73990c1875f94a5551600b04775" }, { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ], "url": "https://git.kernel.org/stable/c/7633407ca4ab8be2916ab214eb44ccebc6a50e1a" }, { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ], "url": "https://git.kernel.org/stable/c/78bbc3d15b6f443acb26e94418c445bac940d414" }, { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ], "url": "https://git.kernel.org/stable/c/b6c29c8f3d7cb67b505f3b2f6c242d52298d1f2e" }, { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d4574bda63906bf69660e001470bfe1a0ac524ae" }, { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ], "url": "https://git.kernel.org/stable/c/dcaa6c31134c0f515600111c38ed7750003e1b9c" }, { "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f9fd47c9d9548f9e47fa60098eab99dde175401d" } ], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [ { "description": [ { "lang": "en", "value": "CWE-415" } ], "source": "nvd@nist.gov", "type": "Primary" } ] }
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Sightings
Author | Source | Type | Date |
---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
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- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.