CVE-2024-47794
- Source
- https://cve.org/CVERecord?id=CVE-2024-47794
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2024-47794.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2024-47794
- Downstream
- Related
- Published
- 2025-01-11T12:25:14Z
- Modified
- 2026-08-12T03:30:44Z
- Severity
-
- 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- bpf: Prevent tailcall infinite loop caused by freplace
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
bpf: Prevent tailcall infinite loop caused by freplace
There is a potential infinite loop issue that can occur when using a combination of tail calls and freplace.
In an upcoming selftest, the attach target for entry_freplace of tailcall_freplace.c is subprog_tc of tc_bpf2bpf.c, while the tail call in entry_freplace leads to entry_tc. This results in an infinite loop:
entry_tc -> subprog_tc -> entry_freplace --tailcall-> entry_tc.
The problem arises because the tail_call_cnt in entry_freplace resets to zero each time entry_freplace is executed, causing the tail call mechanism to never terminate, eventually leading to a kernel panic.
To fix this issue, the solution is twofold:
- Prevent updating a program extended by an freplace program to a prog_array map.
- Prevent extending a program that is already part of a prog_array map with an freplace program.
This ensures that:
- If a program or its subprogram has been extended by an freplace program, it can no longer be updated to a prog_array map.
- If a program has been added to a prog_array map, neither it nor its subprograms can be extended by an freplace program.
Moreover, an extension program should not be tailcalled. As such, return -EINVAL if the program has a type of BPF_PROG_TYPE_EXT when adding it to a prog_array map.
Additionally, fix a minor code style issue by replacing eight spaces with a tab for proper formatting.
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/47xxx/CVE-2024-47794.json" }- References
-
- https://git.kernel.org/stable/c/987aa730bad3e1ef66d9f30182294daa78f6387d
- https://git.kernel.org/stable/c/d6083f040d5d8f8d748462c77e90547097df936e
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/47xxx/CVE-2024-47794.json
- https://nvd.nist.gov/vuln/detail/CVE-2024-47794
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git