Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Fix crash when rebind ccp device for ccp.ko
When CONFIG_CRYPTO_DEV_CCP_DEBUGFS is enabled, rebinding the ccp device causes the following crash:
$ echo ‘0000:0a:00.2’ > /sys/bus/pci/drivers/ccp/unbind $ echo ‘0000:0a:00.2’ > /sys/bus/pci/drivers/ccp/bind
[ 204.976930] BUG: kernel NULL pointer dereference, address: 0000000000000098
[ 204.978026] #PF: supervisor write access in kernel mode
[ 204.979126] #PF: error_code(0x0002) - not-present page
[ 204.980226] PGD 0 P4D 0
[ 204.981317] Oops: Oops: 0002 [#1] SMP NOPTI
…
[ 204.997852] Call Trace:
[ 204.999074]
This patch sets ccp_debugfs_dir to NULL after destroying it in ccp5_debugfs_destroy, allowing the directory dentry to be recreated when rebinding the ccp device.
Tested on AMD Ryzen 7 1700X.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- kernel-uek @ 5.4.17 (+8 more)
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Fix crash when rebind ccp device for ccp.ko
When CONFIG_CRYPTO_DEV_CCP_DEBUGFS is enabled, rebinding the ccp device causes the following crash:
$ echo ‘0000:0a:00.2’ > /sys/bus/pci/drivers/ccp/unbind $ echo ‘0000:0a:00.2’ > /sys/bus/pci/drivers/ccp/bind
[ 204.976930] BUG: kernel NULL pointer dereference, address: 0000000000000098
[ 204.978026] #PF: supervisor write access in kernel mode
[ 204.979126] #PF: error_code(0x0002) - not-present page
[ 204.980226] PGD 0 P4D 0
[ 204.981317] Oops: Oops: 0002 [#1] SMP NOPTI
…
[ 204.997852] Call Trace:
[ 204.999074]
This patch sets ccp_debugfs_dir to NULL after destroying it in ccp5_debugfs_destroy, allowing the directory dentry to be recreated when rebinding the ccp device.
Tested on AMD Ryzen 7 1700X.