CVE-2022-49287

In the Linux kernel, the following vulnerability has been resolved: tpm: fix reference counting for struct tpm_chip The following sequence of operations results in a refcount warning: 1. Open device /dev/tpmrm. 2. Remove module tpm_tis_spi. 3. Write a TPM command to the file descriptor opened at step 1. ------------[ cut here ]------------ WARNING: CPU: 3 PID: 1161 at lib/refcount.c:25 kobject_get+0xa0/0xa4 refcount_t: addition on 0; use-after-free. Modules linked in: tpm_tis_spi tpm_tis_core tpm mdio_bcm_unimac brcmfmac sha256_generic libsha256 sha256_arm hci_uart btbcm bluetooth cfg80211 vc4 brcmutil ecdh_generic ecc snd_soc_core crc32_arm_ce libaes raspberrypi_hwmon ac97_bus snd_pcm_dmaengine bcm2711_thermal snd_pcm snd_timer genet snd phy_generic soundcore [last unloaded: spi_bcm2835] CPU: 3 PID: 1161 Comm: hold_open Not tainted 5.10.0ls-main-dirty #2 Hardware name: BCM2711 [<c0410c3c>] (unwind_backtrace) from [<c040b580>] (show_stack+0x10/0x14) [<c040b580>] (show_stack) from [<c1092174>] (dump_stack+0xc4/0xd8) [<c1092174>] (dump_stack) from [<c0445a30>] (__warn+0x104/0x108) [<c0445a30>] (__warn) from [<c0445aa8>] (warn_slowpath_fmt+0x74/0xb8) [<c0445aa8>] (warn_slowpath_fmt) from [<c08435d0>] (kobject_get+0xa0/0xa4) [<c08435d0>] (kobject_get) from [<bf0a715c>] (tpm_try_get_ops+0x14/0x54 [tpm]) [<bf0a715c>] (tpm_try_get_ops [tpm]) from [<bf0a7d6c>] (tpm_common_write+0x38/0x60 [tpm]) [<bf0a7d6c>] (tpm_common_write [tpm]) from [<c05a7ac0>] (vfs_write+0xc4/0x3c0) [<c05a7ac0>] (vfs_write) from [<c05a7ee4>] (ksys_write+0x58/0xcc) [<c05a7ee4>] (ksys_write) from [<c04001a0>] (ret_fast_syscall+0x0/0x4c) Exception stack(0xc226bfa8 to 0xc226bff0) bfa0: 00000000 000105b4 00000003 beafe664 00000014 00000000 bfc0: 00000000 000105b4 000103f8 00000004 00000000 00000000 b6f9c000 beafe684 bfe0: 0000006c beafe648 0001056c b6eb6944 ---[ end trace d4b8409def9b8b1f ]--- The reason for this warning is the attempt to get the chip->dev reference in tpm_common_write() although the reference counter is already zero. Since commit 8979b02aaf1d ("tpm: Fix reference count to main device") the extra reference used to prevent a premature zero counter is never taken, because the required TPM_CHIP_FLAG_TPM2 flag is never set. Fix this by moving the TPM 2 character device handling from tpm_chip_alloc() to tpm_add_char_device() which is called at a later point in time when the flag has been set in case of TPM2. Commit fdc915f7f719 ("tpm: expose spaces via a device link /dev/tpmrm<n>") already introduced function tpm_devs_release() to release the extra reference but did not implement the required put on chip->devs that results in the call of this function. Fix this by putting chip->devs in tpm_chip_unregister(). Finally move the new implementation for the TPM 2 handling into a new function to avoid multiple checks for the TPM_CHIP_FLAG_TPM2 flag in the good case and error cases.
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:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

25 Mar 2025, 15:24

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: tpm: arreglo del recuento de referencias para struct tpm_chip La siguiente secuencia de operaciones genera una advertencia de recuento de referencias: 1. Abra el dispositivo /dev/tpmrm. 2. Elimine el módulo tpm_tis_spi. 3. Escriba un comando TPM en el descriptor de archivo abierto en el paso 1. ------------[ cortar aquí ]------------ ADVERTENCIA: CPU: 3 PID: 1161 en lib/refcount.c:25 kobject_get+0xa0/0xa4 refcount_t: adición en 0; use-after-free. Módulos vinculados en: tpm_tis_spi tpm_tis_core tpm mdio_bcm_unimac brcmfmac sha256_generic libsha256 sha256_arm hci_uart btbcm bluetooth cfg80211 vc4 brcmutil ecdh_generic ecc snd_soc_core crc32_arm_ce libaes raspberrypi_hwmon ac97_bus snd_pcm_dmaengine bcm2711_thermal snd_pcm snd_timer genet snd phy_generic soundcore [última descarga: spi_bcm2835] CPU: 3 PID: 1161 Comm: hold_open No contaminado 5.10.0ls-main-dirty #2 Nombre del hardware: BCM2711 [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [] (show_stack) desde [] (dump_stack+0xc4/0xd8) [] (dump_stack) from [] (__warn+0x104/0x108) [] (__warn) from [] (warn_slowpath_fmt+0x74/0xb8) [] (warn_slowpath_fmt) from [] (kobject_get+0xa0/0xa4) [] (kobject_get) desde [] (tpm_try_get_ops+0x14/0x54 [tpm]) [] (tpm_try_get_ops [tpm]) desde[] (tpm_common_write+0x38/0x60 [tpm]) [] (tpm_common_write [tpm]) desde[] (vfs_write+0xc4/0x3c0) [] (vfs_write) desde[] (ksys_write+0x58/0xcc) [] (ksys_write) desde[] (ret_fast_syscall+0x0/0x4c) Pila de excepciones (0xc226bfa8 a 0xc226bff0) bfa0: 00000000 000105b4 00000003 beafe664 00000014 00000000 bfc0: 00000000 000105b4 000103f8 00000004 00000000 00000000 b6f9c000 beafe684 bfe0: 0000006c beafe648 0001056c b6eb6944 ---[ fin del seguimiento d4b8409def9b8b1f ]--- El motivo de esta advertencia es el intento de obtener el chip-&gt;dev referencia en tpm_common_write() aunque el contador de referencia ya es cero. Desde el commit 8979b02aaf1d ("tpm: Fix reference count to main device") la referencia adicional utilizada para evitar un contador cero prematuro nunca se toma, porque el indicador TPM_CHIP_FLAG_TPM2 requerido nunca se establece. Corrija esto moviendo la gestión del dispositivo de caracteres TPM 2 de tpm_chip_alloc() a tpm_add_char_device() que se llama en un punto posterior en el tiempo cuando el indicador se ha establecido en el caso de TPM2. el commit fdc915f7f719 ("tpm: exponer espacios a través de un enlace de dispositivo /dev/tpmrm") ya introdujo la función tpm_devs_release() para liberar la referencia adicional pero no implementó la función put en chip-&gt;devs requerida que da como resultado la llamada de esta función. Corrija esto colocando chip-&gt;devs en tpm_chip_unregister(). Finalmente, mueva la nueva implementación para la gestión de TPM 2 a una nueva función para evitar múltiples verificaciones del indicador TPM_CHIP_FLAG_TPM2 en los casos buenos y de error.
First Time Linux
Linux linux Kernel
References () https://git.kernel.org/stable/c/290e05f346d1829e849662c97e42d5ad984f5258 - () https://git.kernel.org/stable/c/290e05f346d1829e849662c97e42d5ad984f5258 - Patch
References () https://git.kernel.org/stable/c/2f928c0d5c02dbab49e8c19d98725c822f6fc409 - () https://git.kernel.org/stable/c/2f928c0d5c02dbab49e8c19d98725c822f6fc409 - Patch
References () https://git.kernel.org/stable/c/473a66f99cb8173c14138c5a5c69bfad04e8f9ac - () https://git.kernel.org/stable/c/473a66f99cb8173c14138c5a5c69bfad04e8f9ac - Patch
References () https://git.kernel.org/stable/c/662893b4f6bd466ff9e1cd454c44c26d32d554fe - () https://git.kernel.org/stable/c/662893b4f6bd466ff9e1cd454c44c26d32d554fe - Patch
References () https://git.kernel.org/stable/c/6e7baf84149fb43950631415de231b3a41915aa3 - () https://git.kernel.org/stable/c/6e7baf84149fb43950631415de231b3a41915aa3 - Patch
References () https://git.kernel.org/stable/c/7e0438f83dc769465ee663bb5dcf8cc154940712 - () https://git.kernel.org/stable/c/7e0438f83dc769465ee663bb5dcf8cc154940712 - Patch
References () https://git.kernel.org/stable/c/a27ed2f3695baf15f9b34d2d7a1f9fc105539a81 - () https://git.kernel.org/stable/c/a27ed2f3695baf15f9b34d2d7a1f9fc105539a81 - Patch
References () https://git.kernel.org/stable/c/cb64bd038beacb4331fe464a36c8b5481e8f51e2 - () https://git.kernel.org/stable/c/cb64bd038beacb4331fe464a36c8b5481e8f51e2 - Patch

27 Feb 2025, 19:15

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

26 Feb 2025, 07:01

Type Values Removed Values Added
New CVE

Information

Published : 2025-02-26 07:01

Updated : 2025-03-25 15:24


NVD link : CVE-2022-49287

Mitre link : CVE-2022-49287

CVE.ORG link : CVE-2022-49287


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-416

Use After Free