CVE-2021-47527
published 2024-05-24CVE-2021-47527: In the Linux kernel, the following vulnerability has been resolved: serial: core: fix transmit-buffer reset and memleak Commit 761ed4a94582 ("tty: serial_core…
PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.25%
16.5th percentile
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")).
Affected
20 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.15.15-1 (bookworm) | linux 5.15.15-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 761ed4a94582ab291aa24dcbea4e01e8936488c8 < 011f6c92b5bf6e1fbfdedc8b5232f64c1c493206 | 011f6c92b5bf6e1fbfdedc8b5232f64c1c493206 |
| linux | linux | >= 761ed4a94582ab291aa24dcbea4e01e8936488c8 < e74d9663fd57640fc3394abb5c76fa95b9cc2f2e | e74d9663fd57640fc3394abb5c76fa95b9cc2f2e |
| linux | linux | >= 761ed4a94582ab291aa24dcbea4e01e8936488c8 < 1179b168fa3f3a6aae3bd140000455a0e58457db | 1179b168fa3f3a6aae3bd140000455a0e58457db |
| linux | linux | >= 761ed4a94582ab291aa24dcbea4e01e8936488c8 < c5da8aa441053958594f94254592bb41264bdfbf | c5da8aa441053958594f94254592bb41264bdfbf |
| linux | linux | >= 761ed4a94582ab291aa24dcbea4e01e8936488c8 < e1722acf4f0d4d67b60f57e08ce16f8b66cd4b8f | e1722acf4f0d4d67b60f57e08ce16f8b66cd4b8f |
| linux | linux | >= 761ed4a94582ab291aa24dcbea4e01e8936488c8 < 64e491c1634b73d3bddc081d08620bdc92ab2c12 | 64e491c1634b73d3bddc081d08620bdc92ab2c12 |
| linux | linux | >= 761ed4a94582ab291aa24dcbea4e01e8936488c8 < 00de977f9e0aa9760d9a79d1e41ff780f74e3424 | 00de977f9e0aa9760d9a79d1e41ff780f74e3424 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.84-1 | 5.10.84-1 |
| linux | linux_kernel | >= 0 < 5.15.15-1 | 5.15.15-1 |
| linux | linux_kernel | >= 0 < 5.15.15-1 | 5.15.15-1 |
| linux | linux_kernel | >= 0 < 5.15.15-1 | 5.15.15-1 |
| linux | linux_kernel | >= 4.10 < 4.14.257 | 4.14.257 |
| linux | linux_kernel | >= 4.15 < 4.19.220 | 4.19.220 |
| linux | linux_kernel | >= 4.20 < 5.4.164 | 5.4.164 |
| linux | linux_kernel | >= 4.9 < 4.9.292 | 4.9.292 |
| linux | linux_kernel | >= 5.11 < 5.15.7 | 5.15.7 |
| linux | linux_kernel | >= 5.5 < 5.10.84 | 5.10.84 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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OSV
CVE-2021-47527: In the Linux kernel, the following vulnerability has been resolved: serial: core: fix transmit-buffer reset and memleak Commit 761ed4a94582 ("tty: ser
osv·2024-05-24·CVSS 5.5
CVE-2021-47527 [MEDIUM] CVE-2021-47527: In the Linux kernel, the following vulnerability has been resolved: serial: core: fix transmit-buffer reset and memleak Commit 761ed4a94582 ("tty: ser
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 a5ba1
Red Hat
kernel: serial: core: fix transmit-buffer reset and memleak
vendor_redhat·2024-05-24·CVSS 5.5
CVE-2021-47527 [MEDIUM] CWE-400 kernel: serial: core: fix transmit-buffer reset and memleak
kernel: serial: core: fix transmit-buffer reset and memleak
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 buffe
Debian
CVE-2021-47527: linux - In the Linux kernel, the following vulnerability has been resolved: serial: cor...
vendor_debian·2021·CVSS 5.5
CVE-2021-47527 [MEDIUM] CVE-2021-47527: linux - In the Linux kernel, the following vulnerability has been resolved: serial: cor...
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 a5ba1
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/00de977f9e0aa9760d9a79d1e41ff780f74e3424https://git.kernel.org/stable/c/011f6c92b5bf6e1fbfdedc8b5232f64c1c493206https://git.kernel.org/stable/c/1179b168fa3f3a6aae3bd140000455a0e58457dbhttps://git.kernel.org/stable/c/64e491c1634b73d3bddc081d08620bdc92ab2c12https://git.kernel.org/stable/c/c5da8aa441053958594f94254592bb41264bdfbfhttps://git.kernel.org/stable/c/e1722acf4f0d4d67b60f57e08ce16f8b66cd4b8fhttps://git.kernel.org/stable/c/e74d9663fd57640fc3394abb5c76fa95b9cc2f2ehttps://git.kernel.org/stable/c/00de977f9e0aa9760d9a79d1e41ff780f74e3424https://git.kernel.org/stable/c/011f6c92b5bf6e1fbfdedc8b5232f64c1c493206https://git.kernel.org/stable/c/1179b168fa3f3a6aae3bd140000455a0e58457dbhttps://git.kernel.org/stable/c/64e491c1634b73d3bddc081d08620bdc92ab2c12https://git.kernel.org/stable/c/c5da8aa441053958594f94254592bb41264bdfbfhttps://git.kernel.org/stable/c/e1722acf4f0d4d67b60f57e08ce16f8b66cd4b8fhttps://git.kernel.org/stable/c/e74d9663fd57640fc3394abb5c76fa95b9cc2f2e
2024-05-24
Published