In the Linux kernel, the following vulnerability has been resolved:
serial: core: fix infinite loop in handle_tx() for PORT_UNKNOWN
uart_write_room() and uart_write() behave inconsistently when
xmit_buf is NULL (which happens for PORT_UNKNOWN ports that were
never properly initialized):
- uart_write_room() returns kfifo_avail() which can be > 0
- uart_write() checks xmit_buf and returns 0 if NULL
This inconsistency causes an infinite loop in drivers that rely on
tty_write_room() to determine if they can write:
while (tty_write_room(tty) > 0) {
written = tty->ops->write(...);
// written is always 0, loop never exits
}
For example, caif_serial's handle_tx() enters an infinite loop when
used with PORT_UNKNOWN serial ports, causing system hangs.
Fix by making uart_write_room() also check xmit_buf and return 0 if
it's NULL, consistent with uart_write().
Reproducer: https://gist.github.com/mrpre/d9a694cc0e19828ee3bc3b37983fde13
References
Configurations
Configuration 1 (hide)
|
History
26 May 2026, 14:26
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* |
|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
| CWE | CWE-835 | |
| First Time |
Linux
Linux linux Kernel |
|
| References | () https://git.kernel.org/stable/c/455ce986fa356ff43a43c0d363ba95fa152f21d5 - Patch | |
| References | () https://git.kernel.org/stable/c/bc70f2b36cf474d5cc8ecbcaf57f3e326fdec67c - Patch | |
| References | () https://git.kernel.org/stable/c/efe85a557186b7fe915572ae93a8f3f78bfd9a22 - Patch |
03 Apr 2026, 16:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-03 16:16
Updated : 2026-05-26 14:26
NVD link : CVE-2026-23472
Mitre link : CVE-2026-23472
CVE.ORG link : CVE-2026-23472
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-835
Loop with Unreachable Exit Condition ('Infinite Loop')