busybox: invalid free or segmentation fault via malformed gzip data (CVE-2021-28831)

decompress_gunzip.c in BusyBox through 1.32.1 mishandles the error bit on the huft_build result pointer, with a resultant invalid free or segmentation fault, via malformed gzip data.

References:

• https://nvd.nist.gov/vuln/detail/CVE-2021-28831
• https://security-tracker.debian.org/tracker/CVE-2021-28831

Patch:

https://git.busybox.net/busybox/commit/?id=f25d254dfd4243698c31a4f3153d4ac72aa9e9bd

Affected branches:

• master: 1.33.0-r5 (8457a320)
• 3.13-stable: 1.32.1-r4 (7acc3190)
• 3.12-stable: 1.31.1-r20 (0d639f13)
• 3.11-stable: 1.31.1-r10 (7332e004)
• 3.10-stable: 1.30.1-r5 (26527b05)