CVE-2025-21727

In the Linux kernel, the following vulnerability has been resolved: padata: fix UAF in padata_reorder A bug was found when run ltp test: BUG: KASAN: slab-use-after-free in padata_find_next+0x29/0x1a0 Read of size 4 at addr ffff88bbfe003524 by task kworker/u113:2/3039206 CPU: 0 PID: 3039206 Comm: kworker/u113:2 Kdump: loaded Not tainted 6.6.0+ Workqueue: pdecrypt_parallel padata_parallel_worker Call Trace: <TASK> dump_stack_lvl+0x32/0x50 print_address_description.constprop.0+0x6b/0x3d0 print_report+0xdd/0x2c0 kasan_report+0xa5/0xd0 padata_find_next+0x29/0x1a0 padata_reorder+0x131/0x220 padata_parallel_worker+0x3d/0xc0 process_one_work+0x2ec/0x5a0 If 'mdelay(10)' is added before calling 'padata_find_next' in the 'padata_reorder' function, this issue could be reproduced easily with ltp test (pcrypt_aead01). This can be explained as bellow: pcrypt_aead_encrypt ... padata_do_parallel refcount_inc(&pd->refcnt); // add refcnt ... padata_do_serial padata_reorder // pd while (1) { padata_find_next(pd, true); // using pd queue_work_on ... padata_serial_worker crypto_del_alg padata_put_pd_cnt // sub refcnt padata_free_shell padata_put_pd(ps->pd); // pd is freed // loop again, but pd is freed // call padata_find_next, UAF } In the padata_reorder function, when it loops in 'while', if the alg is deleted, the refcnt may be decreased to 0 before entering 'padata_find_next', which leads to UAF. As mentioned in [1], do_serial is supposed to be called with BHs disabled and always happen under RCU protection, to address this issue, add synchronize_rcu() in 'padata_free_shell' wait for all _do_serial calls to finish. [1] https://lore.kernel.org/all/20221028160401.cccypv4euxikusiq@parnassus.localdomain/ [2] https://lore.kernel.org/linux-kernel/jfjz5d7zwbytztackem7ibzalm5lnxldi2eofeiczqmqs2m7o6@fq426cwnjtkm/
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

24 Mar 2025, 18:58

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
First Time Linux linux Kernel
Linux
References () https://git.kernel.org/stable/c/0ae2f332cfd2d74cf3ce344ec9938cf3e29c3ccd - () https://git.kernel.org/stable/c/0ae2f332cfd2d74cf3ce344ec9938cf3e29c3ccd - Patch
References () https://git.kernel.org/stable/c/573ac9c70bf7885dc85d82fa44550581bfc3b738 - () https://git.kernel.org/stable/c/573ac9c70bf7885dc85d82fa44550581bfc3b738 - Patch
References () https://git.kernel.org/stable/c/80231f069240d52e98b6a317456c67b2eafd0781 - () https://git.kernel.org/stable/c/80231f069240d52e98b6a317456c67b2eafd0781 - Patch
References () https://git.kernel.org/stable/c/bbccae982e9fa1d7abcb23a5ec81cb0ec883f7de - () https://git.kernel.org/stable/c/bbccae982e9fa1d7abcb23a5ec81cb0ec883f7de - Patch
References () https://git.kernel.org/stable/c/e01780ea4661172734118d2a5f41bc9720765668 - () https://git.kernel.org/stable/c/e01780ea4661172734118d2a5f41bc9720765668 - Patch
References () https://git.kernel.org/stable/c/f3e0b9f790f8e8065d59e67b565a83154d9f3079 - () https://git.kernel.org/stable/c/f3e0b9f790f8e8065d59e67b565a83154d9f3079 - Patch
References () https://git.kernel.org/stable/c/f78170bee51469734b1a306a74fc5f777bb22ba6 - () https://git.kernel.org/stable/c/f78170bee51469734b1a306a74fc5f777bb22ba6 - Patch

13 Mar 2025, 13:15

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/f3e0b9f790f8e8065d59e67b565a83154d9f3079 -
  • () https://git.kernel.org/stable/c/f78170bee51469734b1a306a74fc5f777bb22ba6 -
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: padata: corrección de UAF en padata_reorder Se encontró un error al ejecutar la prueba ltp: ERROR: KASAN: slab-use-after-free in padata_find_next+0x29/0x1a0 Read of size 4 at addr ffff88bbfe003524 by task kworker/u113:2/3039206 CPU: 0 PID: 3039206 Comm: kworker/u113:2 Kdump: loaded Not tainted 6.6.0+ Workqueue: pdecrypt_parallel padata_parallel_worker Call Trace: dump_stack_lvl+0x32/0x50 print_address_description.constprop.0+0x6b/0x3d0 print_report+0xdd/0x2c0 kasan_report+0xa5/0xd0 padata_find_next+0x29/0x1a0 padata_reorder+0x131/0x220 padata_parallel_worker+0x3d/0xc0 process_one_work+0x2ec/0x5a0 If 'mdelay(10)' is added before calling 'padata_find_next' in the 'padata_reorder' function, this issue could be reproduced easily with ltp test (pcrypt_aead01). This can be explained as bellow: pcrypt_aead_encrypt ... padata_do_parallel refcount_inc(&amp;pd-&gt;refcnt); // add refcnt ... padata_do_serial padata_reorder // pd while (1) { padata_find_next(pd, true); // using pd queue_work_on ... padata_serial_worker crypto_del_alg padata_put_pd_cnt // sub refcnt padata_free_shell padata_put_pd(ps-&gt;pd); // pd is freed // loop again, but pd is freed // call padata_find_next, UAF } En la función padata_reorder, cuando se repite en 'while', si se elimina el alg, el refcnt puede disminuirse a 0 antes de ingresar a 'padata_find_next', lo que lleva a UAF. Como se mencionó en [1], se supone que do_serial se debe llamar con los BH deshabilitados y siempre ocurre bajo la protección de RCU, para abordar este problema, agreguesynchronous_rcu() en 'padata_free_shell' y espere a que finalicen todas las llamadas a _do_serial. [1] https://lore.kernel.org/all/20221028160401.cccypv4euxikusiq@parnassus.localdomain/ [2] https://lore.kernel.org/linux-kernel/jfjz5d7zwbytztackem7ibzalm5lnxldi2eofeiczqmqs2m7o6@fq426cwnjtkm/

27 Feb 2025, 18:15

Type Values Removed Values Added
CWE CWE-416
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.8

27 Feb 2025, 02:15

Type Values Removed Values Added
New CVE

Information

Published : 2025-02-27 02:15

Updated : 2025-03-24 18:58


NVD link : CVE-2025-21727

Mitre link : CVE-2025-21727

CVE.ORG link : CVE-2025-21727


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-416

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