CVE-2021-47435
Linux dm NULL Pointer Dereference
Description
In the Linux kernel, the following vulnerability has been resolved: dm: fix mempool NULL pointer race when completing IO dm_io_dec_pending() calls end_io_acct() first and will then dec md in-flight pending count. But if a task is swapping DM table at same time this can result in a crash due to mempool->elements being NULL: task1 task2 do_resume ->do_suspend ->dm_wait_for_completion bio_endio ->clone_endio ->dm_io_dec_pending ->end_io_acct ->wakeup task1 ->dm_swap_table ->__bind ->__bind_mempools ->bioset_exit ->mempool_exit ->free_io [ 67.330330] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 ...... [ 67.330494] pstate: 80400085 (Nzcv daIf +PAN -UAO) [ 67.330510] pc : mempool_free+0x70/0xa0 [ 67.330515] lr : mempool_free+0x4c/0xa0 [ 67.330520] sp : ffffff8008013b20 [ 67.330524] x29: ffffff8008013b20 x28: 0000000000000004 [ 67.330530] x27: ffffffa8c2ff40a0 x26: 00000000ffff1cc8 [ 67.330535] x25: 0000000000000000 x24: ffffffdada34c800 [ 67.330541] x23: 0000000000000000 x22: ffffffdada34c800 [ 67.330547] x21: 00000000ffff1cc8 x20: ffffffd9a1304d80 [ 67.330552] x19: ffffffdada34c970 x18: 000000b312625d9c [ 67.330558] x17: 00000000002dcfbf x16: 00000000000006dd [ 67.330563] x15: 000000000093b41e x14: 0000000000000010 [ 67.330569] x13: 0000000000007f7a x12: 0000000034155555 [ 67.330574] x11: 0000000000000001 x10: 0000000000000001 [ 67.330579] x9 : 0000000000000000 x8 : 0000000000000000 [ 67.330585] x7 : 0000000000000000 x6 : ffffff80148b5c1a [ 67.330590] x5 : ffffff8008013ae0 x4 : 0000000000000001 [ 67.330596] x3 : ffffff80080139c8 x2 : ffffff801083bab8 [ 67.330601] x1 : 0000000000000000 x0 : ffffffdada34c970 [ 67.330609] Call trace: [ 67.330616] mempool_free+0x70/0xa0 [ 67.330627] bio_put+0xf8/0x110 [ 67.330638] dec_pending+0x13c/0x230 [ 67.330644] clone_endio+0x90/0x180 [ 67.330649] bio_endio+0x198/0x1b8 [ 67.330655] dec_pending+0x190/0x230 [ 67.330660] clone_endio+0x90/0x180 [ 67.330665] bio_endio+0x198/0x1b8 [ 67.330673] blk_update_request+0x214/0x428 [ 67.330683] scsi_end_request+0x2c/0x300 [ 67.330688] scsi_io_completion+0xa0/0x710 [ 67.330695] scsi_finish_command+0xd8/0x110 [ 67.330700] scsi_softirq_done+0x114/0x148 [ 67.330708] blk_done_softirq+0x74/0xd0 [ 67.330716] __do_softirq+0x18c/0x374 [ 67.330724] irq_exit+0xb4/0xb8 [ 67.330732] __handle_domain_irq+0x84/0xc0 [ 67.330737] gic_handle_irq+0x148/0x1b0 [ 67.330744] el1_irq+0xe8/0x190 [ 67.330753] lpm_cpuidle_enter+0x4f8/0x538 [ 67.330759] cpuidle_enter_state+0x1fc/0x398 [ 67.330764] cpuidle_enter+0x18/0x20 [ 67.330772] do_idle+0x1b4/0x290 [ 67.330778] cpu_startup_entry+0x20/0x28 [ 67.330786] secondary_start_kernel+0x160/0x170 Fix this by: 1) Establishing pointers to 'struct dm_io' members in dm_io_dec_pending() so that they may be passed into end_io_acct() _after_ free_io() is called. 2) Moving end_io_acct() after free_io().
INFO
Published Date :
May 22, 2024, 7:15 a.m.
Last Modified :
Jan. 31, 2025, 3:16 p.m.
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Remotely Exploitable :
No
Impact Score :
3.6
Exploitability Score :
1.0
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-47435.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-47435 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-47435 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Jan. 31, 2025
Action Type Old Value New Value Added CVSS V3.1 NIST AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE NIST CWE-476 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions up to (excluding) 4.9.313 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.10 up to (excluding) 4.14.278 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.15 up to (excluding) 4.19.242 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.20 up to (excluding) 5.4.193 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.113 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.14.14 *cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:* Changed Reference Type https://git.kernel.org/stable/c/6e506f07c5b561d673dd0b0d8f7f420cc48024fb No Types Assigned https://git.kernel.org/stable/c/6e506f07c5b561d673dd0b0d8f7f420cc48024fb Patch Changed Reference Type https://git.kernel.org/stable/c/6e506f07c5b561d673dd0b0d8f7f420cc48024fb No Types Assigned https://git.kernel.org/stable/c/6e506f07c5b561d673dd0b0d8f7f420cc48024fb Patch Changed Reference Type https://git.kernel.org/stable/c/9e07272cca2ed76f7f6073f4444b1143828c8d87 No Types Assigned https://git.kernel.org/stable/c/9e07272cca2ed76f7f6073f4444b1143828c8d87 Patch Changed Reference Type https://git.kernel.org/stable/c/9e07272cca2ed76f7f6073f4444b1143828c8d87 No Types Assigned https://git.kernel.org/stable/c/9e07272cca2ed76f7f6073f4444b1143828c8d87 Patch Changed Reference Type https://git.kernel.org/stable/c/9fb7cd5c7fef0f1c982e3cd27745a0dec260eaed No Types Assigned https://git.kernel.org/stable/c/9fb7cd5c7fef0f1c982e3cd27745a0dec260eaed Patch Changed Reference Type https://git.kernel.org/stable/c/9fb7cd5c7fef0f1c982e3cd27745a0dec260eaed No Types Assigned https://git.kernel.org/stable/c/9fb7cd5c7fef0f1c982e3cd27745a0dec260eaed Patch Changed Reference Type https://git.kernel.org/stable/c/ad1393b92e5059218d055bfec8f4946d85ad04c4 No Types Assigned https://git.kernel.org/stable/c/ad1393b92e5059218d055bfec8f4946d85ad04c4 Patch Changed Reference Type https://git.kernel.org/stable/c/ad1393b92e5059218d055bfec8f4946d85ad04c4 No Types Assigned https://git.kernel.org/stable/c/ad1393b92e5059218d055bfec8f4946d85ad04c4 Patch Changed Reference Type https://git.kernel.org/stable/c/d208b89401e073de986dc891037c5a668f5d5d95 No Types Assigned https://git.kernel.org/stable/c/d208b89401e073de986dc891037c5a668f5d5d95 Patch Changed Reference Type https://git.kernel.org/stable/c/d208b89401e073de986dc891037c5a668f5d5d95 No Types Assigned https://git.kernel.org/stable/c/d208b89401e073de986dc891037c5a668f5d5d95 Patch Changed Reference Type https://git.kernel.org/stable/c/d29c78d3f9c5d2604548c1065bf1ec212728ea61 No Types Assigned https://git.kernel.org/stable/c/d29c78d3f9c5d2604548c1065bf1ec212728ea61 Patch Changed Reference Type https://git.kernel.org/stable/c/d29c78d3f9c5d2604548c1065bf1ec212728ea61 No Types Assigned https://git.kernel.org/stable/c/d29c78d3f9c5d2604548c1065bf1ec212728ea61 Patch Changed Reference Type https://git.kernel.org/stable/c/d35aef9c60d310eff3eaddacce301efe877e2b7c No Types Assigned https://git.kernel.org/stable/c/d35aef9c60d310eff3eaddacce301efe877e2b7c Patch Changed Reference Type https://git.kernel.org/stable/c/d35aef9c60d310eff3eaddacce301efe877e2b7c No Types Assigned https://git.kernel.org/stable/c/d35aef9c60d310eff3eaddacce301efe877e2b7c Patch -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/6e506f07c5b561d673dd0b0d8f7f420cc48024fb Added Reference https://git.kernel.org/stable/c/9e07272cca2ed76f7f6073f4444b1143828c8d87 Added Reference https://git.kernel.org/stable/c/9fb7cd5c7fef0f1c982e3cd27745a0dec260eaed Added Reference https://git.kernel.org/stable/c/ad1393b92e5059218d055bfec8f4946d85ad04c4 Added Reference https://git.kernel.org/stable/c/d208b89401e073de986dc891037c5a668f5d5d95 Added Reference https://git.kernel.org/stable/c/d29c78d3f9c5d2604548c1065bf1ec212728ea61 Added Reference https://git.kernel.org/stable/c/d35aef9c60d310eff3eaddacce301efe877e2b7c -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 28, 2024
Action Type Old Value New Value -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 22, 2024
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: dm: fix mempool NULL pointer race when completing IO dm_io_dec_pending() calls end_io_acct() first and will then dec md in-flight pending count. But if a task is swapping DM table at same time this can result in a crash due to mempool->elements being NULL: task1 task2 do_resume ->do_suspend ->dm_wait_for_completion bio_endio ->clone_endio ->dm_io_dec_pending ->end_io_acct ->wakeup task1 ->dm_swap_table ->__bind ->__bind_mempools ->bioset_exit ->mempool_exit ->free_io [ 67.330330] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 ...... [ 67.330494] pstate: 80400085 (Nzcv daIf +PAN -UAO) [ 67.330510] pc : mempool_free+0x70/0xa0 [ 67.330515] lr : mempool_free+0x4c/0xa0 [ 67.330520] sp : ffffff8008013b20 [ 67.330524] x29: ffffff8008013b20 x28: 0000000000000004 [ 67.330530] x27: ffffffa8c2ff40a0 x26: 00000000ffff1cc8 [ 67.330535] x25: 0000000000000000 x24: ffffffdada34c800 [ 67.330541] x23: 0000000000000000 x22: ffffffdada34c800 [ 67.330547] x21: 00000000ffff1cc8 x20: ffffffd9a1304d80 [ 67.330552] x19: ffffffdada34c970 x18: 000000b312625d9c [ 67.330558] x17: 00000000002dcfbf x16: 00000000000006dd [ 67.330563] x15: 000000000093b41e x14: 0000000000000010 [ 67.330569] x13: 0000000000007f7a x12: 0000000034155555 [ 67.330574] x11: 0000000000000001 x10: 0000000000000001 [ 67.330579] x9 : 0000000000000000 x8 : 0000000000000000 [ 67.330585] x7 : 0000000000000000 x6 : ffffff80148b5c1a [ 67.330590] x5 : ffffff8008013ae0 x4 : 0000000000000001 [ 67.330596] x3 : ffffff80080139c8 x2 : ffffff801083bab8 [ 67.330601] x1 : 0000000000000000 x0 : ffffffdada34c970 [ 67.330609] Call trace: [ 67.330616] mempool_free+0x70/0xa0 [ 67.330627] bio_put+0xf8/0x110 [ 67.330638] dec_pending+0x13c/0x230 [ 67.330644] clone_endio+0x90/0x180 [ 67.330649] bio_endio+0x198/0x1b8 [ 67.330655] dec_pending+0x190/0x230 [ 67.330660] clone_endio+0x90/0x180 [ 67.330665] bio_endio+0x198/0x1b8 [ 67.330673] blk_update_request+0x214/0x428 [ 67.330683] scsi_end_request+0x2c/0x300 [ 67.330688] scsi_io_completion+0xa0/0x710 [ 67.330695] scsi_finish_command+0xd8/0x110 [ 67.330700] scsi_softirq_done+0x114/0x148 [ 67.330708] blk_done_softirq+0x74/0xd0 [ 67.330716] __do_softirq+0x18c/0x374 [ 67.330724] irq_exit+0xb4/0xb8 [ 67.330732] __handle_domain_irq+0x84/0xc0 [ 67.330737] gic_handle_irq+0x148/0x1b0 [ 67.330744] el1_irq+0xe8/0x190 [ 67.330753] lpm_cpuidle_enter+0x4f8/0x538 [ 67.330759] cpuidle_enter_state+0x1fc/0x398 [ 67.330764] cpuidle_enter+0x18/0x20 [ 67.330772] do_idle+0x1b4/0x290 [ 67.330778] cpu_startup_entry+0x20/0x28 [ 67.330786] secondary_start_kernel+0x160/0x170 Fix this by: 1) Establishing pointers to 'struct dm_io' members in dm_io_dec_pending() so that they may be passed into end_io_acct() _after_ free_io() is called. 2) Moving end_io_acct() after free_io(). Added Reference kernel.org https://git.kernel.org/stable/c/9fb7cd5c7fef0f1c982e3cd27745a0dec260eaed [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/d35aef9c60d310eff3eaddacce301efe877e2b7c [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/9e07272cca2ed76f7f6073f4444b1143828c8d87 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/ad1393b92e5059218d055bfec8f4946d85ad04c4 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/d29c78d3f9c5d2604548c1065bf1ec212728ea61 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/6e506f07c5b561d673dd0b0d8f7f420cc48024fb [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/d208b89401e073de986dc891037c5a668f5d5d95 [No types assigned]
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-47435 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-47435
weaknesses.