UBUNTU-CVE-2026-98584: Infoleak

In the Linux kernel, the following vulnerability has been resolved: net/sched: fix potential stack infoleak in emtextdump() emtextdump() allocates struct tcfemtext on the stack without zeroing it. strscpy() writes the algorithm name and a NUL terminator into conf.algo[], leaving the remaining bytes uninitialised. nlaputnohdr() then copies the full struct to the netlink response. KMSAN on Linux 7.2-rc6 reports two kernel-infoleak splats from this path, one triggered via "tc filter show" and one via a raw RTMGETTFILTER dump: BUG: KMSAN: kernel-infoleak in copytoiter+0x1c9/0x2620 nlaputnohdr+0x83/0x130 emtextdump+0x291/0x550 Local variable conf created at: emtextdump+0x5d/0x550 Bytes 168-179 of 199 are uninitialized I am not certain whether this constitutes a real security problem in practice: the test was conducted in a controlled KMSAN environment and the leaked stack bytes may or may not carry sensitive data on actual production kernels. I am reporting it because KMSAN flagged it as a kernel-infoleak and the fix is straightforward. I can provide a userspace reproducer on request. The original code used strncpy() which zero-pads to the destination size. Commit b04202d6065c ("net/sched: replace strncpy with strscpy") replaced it with strscpy(), which does not pad, creating this condition. Zero-initialising the struct closes it.