Lucene search

K
debiancveDebian Security Bug TrackerDEBIANCVE:CVE-2021-47527
HistoryMay 24, 2024 - 3:15 p.m.

CVE-2021-47527

2024-05-2415:15:15
Debian Security Bug Tracker
security-tracker.debian.org
2
linux kernel
insecure
vulnerability

6.8 Medium

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

10.3%

In the Linux kernel, the following vulnerability has been resolved: serial: core: fix transmit-buffer reset and memleak Commit 761ed4a94582 (“tty: serial_core: convert uart_close to use tty_port_close”) converted serial core to use tty_port_close() but failed to notice that the transmit buffer still needs to be freed on final close. Not freeing the transmit buffer means that the buffer is no longer cleared on next open so that any ioctl() waiting for the buffer to drain might wait indefinitely (e.g. on termios changes) or that stale data can end up being transmitted in case tx is restarted. Furthermore, the buffer of any port that has been opened would leak on driver unbind. Note that the port lock is held when clearing the buffer pointer due to the ldisc race worked around by commit a5ba1d95e46e (“uart: fix race between uart_put_char() and uart_shutdown()”). Also note that the tty-port shutdown() callback is not called for console ports so it is not strictly necessary to free the buffer page after releasing the lock (cf. d72402145ace (“tty/serial: do not free trasnmit buffer page under port lock”)).

6.8 Medium

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

10.3%

Related for DEBIANCVE:CVE-2021-47527