In the Linux kernel, the following vulnerability has been resolved:
fpga: bridge: add owner module and take its refcount
The current implementation of the fpga bridge assumes that the low-level
module registers a driver for the parent device and uses its owner pointer
to take the module’s refcount. This approach is problematic since it can
lead to a null pointer dereference while attempting to get the bridge if
the parent device does not have a driver.
To address this problem, add a module owner pointer to the fpga_bridge
struct and use it to take the module’s refcount. Modify the function for
registering a bridge to take an additional owner module parameter and
rename it to avoid conflicts. Use the old function name for a helper macro
that automatically sets the module that registers the bridge as the owner.
This ensures compatibility with existing low-level control modules and
reduces the chances of registering a bridge without setting the owner.
Also, update the documentation to keep it consistent with the new interface
for registering an fpga bridge.
Other changes: opportunistically move put_device() from __fpga_bridge_get()
to fpga_bridge_get() and of_fpga_bridge_get() to improve code clarity since
the bridge device is taken in these functions.
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"Documentation/driver-api/fpga/fpga-bridge.rst",
"drivers/fpga/fpga-bridge.c",
"include/linux/fpga/fpga-bridge.h"
],
"versions": [
{
"version": "21aeda950c5f",
"lessThan": "d7c4081c54a1",
"status": "affected",
"versionType": "git"
},
{
"version": "21aeda950c5f",
"lessThan": "6896b6b2e2d9",
"status": "affected",
"versionType": "git"
},
{
"version": "21aeda950c5f",
"lessThan": "1da11f822042",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"Documentation/driver-api/fpga/fpga-bridge.rst",
"drivers/fpga/fpga-bridge.c",
"include/linux/fpga/fpga-bridge.h"
],
"versions": [
{
"version": "4.10",
"status": "affected"
},
{
"version": "0",
"lessThan": "4.10",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.6.33",
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.9.4",
"lessThanOrEqual": "6.9.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.10",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]