In the Linux kernel, the following vulnerability has been resolved:
net: dsa: microchip: Added the condition for scheduling ksz_mib_read_work
When the ksz module is installed and removed using rmmod, kernel crashes
with null pointer dereferrence error. During rmmod, ksz_switch_remove
function tries to cancel the mib_read_workqueue using
cancel_delayed_work_sync routine and unregister switch from dsa.
During dsa_unregister_switch it calls ksz_mac_link_down, which in turn
reschedules the workqueue since mib_interval is non-zero.
Due to which queue executed after mib_interval and it tries to access
dp->slave. But the slave is unregistered in the ksz_switch_remove
function. Hence kernel crashes.
To avoid this crash, before canceling the workqueue, resetted the
mib_interval to 0.
v1 -> v2:
-Removed the if condition in ksz_mib_read_work
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/net/dsa/microchip/ksz_common.c"
],
"versions": [
{
"version": "469b390e1ba3",
"lessThan": "f2e1de075018",
"status": "affected",
"versionType": "git"
},
{
"version": "469b390e1ba3",
"lessThan": "383239a33cf2",
"status": "affected",
"versionType": "git"
},
{
"version": "469b390e1ba3",
"lessThan": "ef1100ef20f2",
"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/net/dsa/microchip/ksz_common.c"
],
"versions": [
{
"version": "5.7",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.7",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.10.75",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.14.14",
"lessThanOrEqual": "5.14.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.15",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]