CVE-2026-43197

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

netconsole: avoid OOB reads, msg is not nul-terminated

msg passed to netconsole from the console subsystem is not guaranteed

to be nul-terminated. Before recent

commit 7eab73b18630 ("netconsole: convert to NBCON console infrastructure")

the message would be placed in printk_shared_pbufs, a static global

buffer, so KASAN had harder time catching OOB accesses. Now we see:

printk: console [netcon_ext0] enabled

BUG: KASAN: slab-out-of-bounds in string+0x1f7/0x240

Read of size 1 at addr ffff88813b6d4c00 by task pr/netcon_ext0/594

CPU: 65 UID: 0 PID: 594 Comm: pr/netcon_ext0 Not tainted 6.19.0-11754-g4246fd6547c9

Call Trace:

kasan_report+0xe4/0x120

string+0x1f7/0x240

vsnprintf+0x655/0xba0

scnprintf+0xba/0x120

netconsole_write+0x3fe/0xa10

nbcon_emit_next_record+0x46e/0x860

nbcon_kthread_func+0x623/0x750

Allocated by task 1:

nbcon_alloc+0x1ea/0x450

register_console+0x26b/0xe10

init_netconsole+0xbb0/0xda0

The buggy address belongs to the object at ffff88813b6d4000

which belongs to the cache kmalloc-4k of size 4096

The buggy address is located 0 bytes to the right of

allocated 3072-byte region [ffff88813b6d4000, ffff88813b6d4c00)