CVSS: 8.8EPSS: 0%CPEs: 1EXPL: 0CVE-2021-4440 – x86/xen: Drop USERGS_SYSRET64 paravirt call
https://notcve.org/view.php?id=CVE-2021-4440
In the Linux kernel, the following vulnerability has been resolved: x86/xen: Drop USERGS_SYSRET64 paravirt call commit afd30525a659ac0ae0904f0cb4a2ca75522c3123 upstream. USERGS_SYSRET64 is used to return from a syscall via SYSRET, but a Xen PV guest will nevertheless use the IRET hypercall, as there is no sysret PV hypercall defined. So instead of testing all the prerequisites for doing a sysret and then mangling the stack for Xen PV again for doing an iret just use the iret exit from the beginning. This can easily be done via an ALTERNATIVE like it is done for the sysenter compat case already. It should be noted that this drops the optimization in Xen for not restoring a few registers when returning to user mode, but it seems as if the saved instructions in the kernel more than compensate for this drop (a kernel build in a Xen PV guest was slightly faster with this patch applied). While at it remove the stale sysret32 remnants. [ pawan: Brad Spengler and Salvatore Bonaccorso <carnil@debian.org> reported a problem with the 5.10 backport commit edc702b4a820 ("x86/entry_64: Add VERW just before userspace transition"). When CONFIG_PARAVIRT_XXL=y, CLEAR_CPU_BUFFERS is not executed in syscall_return_via_sysret path as USERGS_SYSRET64 is runtime patched to: .cpu_usergs_sysret64 = { 0x0f, 0x01, 0xf8, 0x48, 0x0f, 0x07 }, // swapgs; sysretq which is missing CLEAR_CPU_BUFFERS. It turns out dropping USERGS_SYSRET64 simplifies the code, allowing CLEAR_CPU_BUFFERS to be explicitly added to syscall_return_via_sysret path. Below is with CONFIG_PARAVIRT_XXL=y and this patch applied: syscall_return_via_sysret: ... <+342>: swapgs <+345>: xchg %ax,%ax <+347>: verw -0x1a2(%rip) <------ <+354>: sysretq ] En el kernel de Linux, se resolvió la siguiente vulnerabilidad: x86/xen: elimine el commit de llamada paravirt USERGS_SYSRET64 afd30525a659ac0ae0904f0cb4a2ca75522c3123 en sentido ascendente. USERGS_SYSRET64 se usa para regresar de una llamada al sistema a través de SYSRET, pero un invitado Xen PV usará la hiperllamada IRET, ya que no hay ninguna hiperllamada PV sysret definida. Entonces, en lugar de probar todos los requisitos previos para hacer un sysret y luego alterar la pila para Xen PV nuevamente para hacer un iret, simplemente use la salida iret desde el principio. • https://git.kernel.org/stable/c/cea750c99d8f6391080c420f811a46b21bad7cf4 https://git.kernel.org/stable/c/1424ab4bb386df9cc590c73afa55f13e9b00dea2 https://grsecurity.net/cve-2021-4440_linux_cna_case_study • CWE-400: Uncontrolled Resource Consumption •
CVSS: -EPSS: 0%CPEs: 2EXPL: 0CVE-2024-37026 – drm/xe: Only use reserved BCS instances for usm migrate exec queue
https://notcve.org/view.php?id=CVE-2024-37026
In the Linux kernel, the following vulnerability has been resolved: drm/xe: Only use reserved BCS instances for usm migrate exec queue The GuC context scheduling queue is 2 entires deep, thus it is possible for a migration job to be stuck behind a fault if migration exec queue shares engines with user jobs. This can deadlock as the migrate exec queue is required to service page faults. Avoid deadlock by only using reserved BCS instances for usm migrate exec queue. (cherry picked from commit 04f4a70a183a688a60fe3882d6e4236ea02cfc67) • https://git.kernel.org/stable/c/a043fbab7af54c64017269dc96f43f441ed4bcaf https://git.kernel.org/stable/c/92deed4a9bfd9ef187764225bba530116c49e15c https://git.kernel.org/stable/c/c8ea2c31f5ea437199b239d76ad5db27343edb0c •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2024-37021 – fpga: manager: add owner module and take its refcount
https://notcve.org/view.php?id=CVE-2024-37021
In the Linux kernel, the following vulnerability has been resolved: fpga: manager: add owner module and take its refcount The current implementation of the fpga manager 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 manager if the parent device does not have a driver. To address this problem, add a module owner pointer to the fpga_manager struct and use it to take the module's refcount. Modify the functions for registering the manager to take an additional owner module parameter and rename them to avoid conflicts. Use the old function names for helper macros that automatically set the module that registers the manager as the owner. This ensures compatibility with existing low-level control modules and reduces the chances of registering a manager without setting the owner. Also, update the documentation to keep it consistent with the new interface for registering an fpga manager. Other changes: opportunistically move put_device() from __fpga_mgr_get() to fpga_mgr_get() and of_fpga_mgr_get() to improve code clarity since the manager device is taken in these functions. • https://git.kernel.org/stable/c/654ba4cc0f3ed7c0f08bfb39f66059d8c42943ee https://git.kernel.org/stable/c/2da62a139a6221a345db4eb9f4f1c4b0937c89ad https://git.kernel.org/stable/c/62ac496a01c9337a11362cea427038ba621ca9eb https://git.kernel.org/stable/c/4d4d2d4346857bf778fafaa97d6f76bb1663e3c9 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2024-36479 – fpga: bridge: add owner module and take its refcount
https://notcve.org/view.php?id=CVE-2024-36479
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. • https://git.kernel.org/stable/c/21aeda950c5f84a8351b862816d832120b217a9b https://git.kernel.org/stable/c/d7c4081c54a1d4068de9440957303a76f9e5c95b https://git.kernel.org/stable/c/6896b6b2e2d9ec4e1b0acb4c1698a75a4b34d125 https://git.kernel.org/stable/c/1da11f822042eb6ef4b6064dc048f157a7852529 •
CVSS: -EPSS: 0%CPEs: 6EXPL: 0CVE-2024-35247 – fpga: region: add owner module and take its refcount
https://notcve.org/view.php?id=CVE-2024-35247
In the Linux kernel, the following vulnerability has been resolved: fpga: region: add owner module and take its refcount The current implementation of the fpga region 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 region during programming if the parent device does not have a driver. To address this problem, add a module owner pointer to the fpga_region struct and use it to take the module's refcount. Modify the functions for registering a region to take an additional owner module parameter and rename them to avoid conflicts. Use the old function names for helper macros that automatically set the module that registers the region as the owner. This ensures compatibility with existing low-level control modules and reduces the chances of registering a region without setting the owner. Also, update the documentation to keep it consistent with the new interface for registering an fpga region. • https://git.kernel.org/stable/c/0fa20cdfcc1f68847cdfc47824476301eedc8297 https://git.kernel.org/stable/c/26e6e25d742e29885cf44274fcf6b744366c4702 https://git.kernel.org/stable/c/9b4eee8572dcf82b2ed17d9a328c7fb87df2f0e8 https://git.kernel.org/stable/c/75a001914a8d2ccdcbe4b8cc7e94ac71d0e66093 https://git.kernel.org/stable/c/4d7d12b643c00e7eea51b49a60a2ead182633ec8 https://git.kernel.org/stable/c/2279c09c36165ccded4d506d11a7714e13b56019 https://git.kernel.org/stable/c/b7c0e1ecee403a43abc89eb3e75672b01ff2ece9 •