Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen()
Patch series “lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen()”, v2.
This series fixes an off-by-one out-of-bounds read in ucs2_strnlen().
The first patch is the real fix, the second patch comes as a bonus and fixes the code indentation.
This patch (of 2):
ucs2_strnlen() checks the current character before checking whether the caller-provided maximum length has been reached. If the input is not NUL-terminated within that bound, the loop can read one ucs2_char_t past the limit.
Test the length before dereferencing to prevent an off-by-one out-of-bounds read.
Details
- Affected product:
- Debian 10 ELS , Debian 11 ELS , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 5.4.0 (+4 more)