Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
dm mirror: fix integer overflow in create_dirty_log()
The argument count calculation in create_dirty_log() performs
*args_used = 2 + param_count before validating against argc. When a
user provides a param_count close to UINT_MAX via the device mapper
table string, this unsigned addition wraps around to a small value,
causing the subsequent argc < *args_used check to be bypassed.
The overflowed param_count is then passed as argc to dm_dirty_log_create(), where it can cause out-of-bounds reads on the argv array.
Fix by comparing param_count against argc - 2 before performing the addition, following the same pattern used by parse_features() in the same file. Since argc >= 2 is already guaranteed, the subtraction is safe.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 5.14.0 (+5 more)
In the Linux kernel, the following vulnerability has been resolved:
dm mirror: fix integer overflow in create_dirty_log()
The argument count calculation in create_dirty_log() performs
*args_used = 2 + param_count before validating against argc. When a
user provides a param_count close to UINT_MAX via the device mapper
table string, this unsigned addition wraps around to a small value,
causing the subsequent argc < *args_used check to be bypassed.
The overflowed param_count is then passed as argc to dm_dirty_log_create(), where it can cause out-of-bounds reads on the argv array.
Fix by comparing param_count against argc - 2 before performing the addition, following the same pattern used by parse_features() in the same file. Since argc >= 2 is already guaranteed, the subtraction is safe.