bpf: Reject pkt arguments in mutating subprogs
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 7.2.9
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Reject pkt arguments in mutating subprogs The verifier tracks changes in how PTR_TO_PACKET registers' bounds are modified across subprog boundaries. PTR_TO_PACKET registers are actually passed as PTR_TO_MEM, which is assumed valid for the entire call. This is not the case with packet memory, where a pskb_* call may invalidate its memory region. Reject BPF code that passes PTR_TO_PACKET pointers to subprogs that may mutate a packet. We cannot pass the pointer as a true PTR_TO_PACKET because we would also need to somehow pass the PTR_TO_PACKET_META or PTR_TO_PACKET_END to the subprog. Since we cannot avoid representing the pointer in the subprog as PTR_TO_MEM, only permit it if the subprog is guaranteed not to mutate the packet.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 0b6b2bb9b90ad1e2d94d18f626258a1dbbdee0ea; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in a6c1edfbe240e4377038a0e1d233ad81fde9a21b; fixed in 7.2.9
- Linux Linux
Version range not reported
- KernelLinux
fixed in 7.2.9