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”)).
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/tty/serial/serial_core.c"
],
"versions": [
{
"version": "761ed4a94582",
"lessThan": "011f6c92b5bf",
"status": "affected",
"versionType": "git"
},
{
"version": "761ed4a94582",
"lessThan": "e74d9663fd57",
"status": "affected",
"versionType": "git"
},
{
"version": "761ed4a94582",
"lessThan": "1179b168fa3f",
"status": "affected",
"versionType": "git"
},
{
"version": "761ed4a94582",
"lessThan": "c5da8aa44105",
"status": "affected",
"versionType": "git"
},
{
"version": "761ed4a94582",
"lessThan": "e1722acf4f0d",
"status": "affected",
"versionType": "git"
},
{
"version": "761ed4a94582",
"lessThan": "64e491c1634b",
"status": "affected",
"versionType": "git"
},
{
"version": "761ed4a94582",
"lessThan": "00de977f9e0a",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/tty/serial/serial_core.c"
],
"versions": [
{
"version": "4.9",
"status": "affected"
},
{
"version": "0",
"lessThan": "4.9",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "4.9.292",
"lessThanOrEqual": "4.9.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "4.14.257",
"lessThanOrEqual": "4.14.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "4.19.220",
"lessThanOrEqual": "4.19.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.4.164",
"lessThanOrEqual": "5.4.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.10.84",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.15.7",
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.16",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]
git.kernel.org/stable/c/00de977f9e0aa9760d9a79d1e41ff780f74e3424
git.kernel.org/stable/c/011f6c92b5bf6e1fbfdedc8b5232f64c1c493206
git.kernel.org/stable/c/1179b168fa3f3a6aae3bd140000455a0e58457db
git.kernel.org/stable/c/64e491c1634b73d3bddc081d08620bdc92ab2c12
git.kernel.org/stable/c/c5da8aa441053958594f94254592bb41264bdfbf
git.kernel.org/stable/c/e1722acf4f0d4d67b60f57e08ce16f8b66cd4b8f
git.kernel.org/stable/c/e74d9663fd57640fc3394abb5c76fa95b9cc2f2e