Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
dm-pcache: reject option groups without values
The pcache target parses optional arguments as name/value pairs. A table that advertises one optional argument and supplies only a recognized option name, for example “cache_mode”, reaches parse_cache_opts() with argc == 1. The parser consumes the name, decrements argc to zero, then calls dm_shift_arg() again for the value. dm_shift_arg() returns NULL when no arguments remain, and the following strcmp() dereferences that NULL pointer.
Check that each recognized option has a value before consuming it. This keeps valid “cache_mode writeback” and “data_crc true/false” tables unchanged while making malformed tables fail during target construction with a precise missing-value error.
Details
- Affected product:
- Debian 10 ELS
- Affected packages:
- linux @ 4.19.0