CVE-2024-50142

In the Linux kernel, the following vulnerability has been resolved:

xfrm: validate new SAs prefixlen using SA family when sel.family is unset

This expands the validation introduced in commit 07bf7908950a (xfrm: Validate address prefix lengths in the xfrm selector.)

syzbot created an SA with usersa.sel.family = AF_UNSPEC usersa.sel.prefixlen_s = 128 usersa.family = AF_INET

Because of the AF_UNSPEC selector, verify_newsa_info doesnt put limits on prefixlen_{s,d}. But then copy_from_user_state sets x->sel.family to usersa.family (AF_INET). Do the same conversion in verify_newsa_info before validating prefixlen_{s,d}, since thats how prefixlen is going to be used later on.

Affected Software

References

• https://git.kernel.org/stable/c/2d08a6c31c65f23db71a5385ee9cf9d8f9a67a71
• https://git.kernel.org/stable/c/3f0ab59e6537c6a8f9e1b355b48f9c05a76e8563
• https://git.kernel.org/stable/c/401ad99a5ae7180dd9449eac104cb755f442e7f3
• https://git.kernel.org/stable/c/7d9868180bd1e4cf37e7c5067362658971162366
• https://git.kernel.org/stable/c/8df5cd51fd70c33aa1776e5cbcd82b0a86649d73
• https://git.kernel.org/stable/c/bce1afaa212ec380bf971614f70909a27882b862
• https://git.kernel.org/stable/c/e68dd80ba498265d2266b12dc3459164f4ff0c4a
• https://git.kernel.org/stable/c/f31398570acf0f0804c644006f7bfa9067106b0a