Bug 1226655 (CVE-2024-38574)

Summary: VUL-0: CVE-2024-38574: kernel: libbpf: prevent null-pointer dereference when prog to load has no BTF
Product: [Novell Products] SUSE Security Incidents Reporter: SMASH SMASH <smash_bz>
Component: IncidentsAssignee: Security Team bot <security-team>
Status: RESOLVED INVALID QA Contact: Security Team bot <security-team>
Severity: Normal    
Priority: P3 - Medium CC: camila.matos, mhocko
Version: unspecified   
Target Milestone: ---   
Hardware: Other   
OS: Other   
URL: https://smash.suse.de/issue/411440/
Whiteboard: CVSSv3.1:SUSE:CVE-2024-38574:5.5:(AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Found By: Security Response Team Services Priority:
Business Priority: Blocker: ---
Marketing QA Status: --- IT Deployment: ---

Description SMASH SMASH 2024-06-20 16:42:33 UTC 
In the Linux kernel, the following vulnerability has been resolved:

libbpf: Prevent null-pointer dereference when prog to load has no BTF

In bpf_objec_load_prog(), there's no guarantee that obj->btf is non-NULL
when passing it to btf__fd(), and this function does not perform any
check before dereferencing its argument (as bpf_object__btf_fd() used to
do). As a consequence, we get segmentation fault errors in bpftool (for
example) when trying to load programs that come without BTF information.

v2: Keep btf__fd() in the fix instead of reverting to bpf_object__btf_fd().

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-38574
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2024/CVE-2024-38574.mbox
https://git.kernel.org/stable/c/ef80b59acfa4dee4b5eaccb15572b69248831104
https://git.kernel.org/stable/c/1fd91360a75833b7110af9834ae26c977e1273e0
https://git.kernel.org/stable/c/9bf48fa19a4b1d186e08b20bf7e5de26a15644fb
https://www.cve.org/CVERecord?id=CVE-2024-38574