Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
xfrm: xfrm_alloc_spi shouldn’t use 0 as SPI
x->id.spi == 0 means “no SPI assigned”, but since commit 94f39804d891 (“xfrm: Duplicate SPI Handling”), we now create states and add them to the byspi list with this value.
__xfrm_state_delete doesn’t remove those states from the byspi list, since they shouldn’t be there, and this shows up as a UAF the next time we go through the byspi list.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 7 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , Ubuntu 20.04 ELS
- Affected packages:
- kernel @ 3.10.0 (+4 more)
In the Linux kernel, the following vulnerability has been resolved:
xfrm: xfrm_alloc_spi shouldn’t use 0 as SPI
x->id.spi == 0 means “no SPI assigned”, but since commit 94f39804d891 (“xfrm: Duplicate SPI Handling”), we now create states and add them to the byspi list with this value.
__xfrm_state_delete doesn’t remove those states from the byspi list, since they shouldn’t be there, and this shows up as a UAF the next time we go through the byspi list.