On Fri, Jan 17, 2025 at 8:39 AM Mel Gorman <[email protected]> wrote: > > There is a submenu for 'Kernel hardening options' under "Security". > Move HARDENED_USERCOPY under the hardening options as it is clearly > related. > > Signed-off-by: Mel Gorman <[email protected]> > --- > security/Kconfig | 12 ------------ > security/Kconfig.hardening | 16 ++++++++++++++++ > 2 files changed, 16 insertions(+), 12 deletions(-)
Agree with Kees' comment regarding "Bounds checking" instead of "String manipulation", but beyond that this is fine with me. Acked-by: Paul Moore <[email protected]> > diff --git a/security/Kconfig b/security/Kconfig > index 28e685f53bd1..fe7346dc4bc3 100644 > --- a/security/Kconfig > +++ b/security/Kconfig > @@ -159,18 +159,6 @@ config LSM_MMAP_MIN_ADDR > this low address space will need the permission specific to the > systems running LSM. > > -config HARDENED_USERCOPY > - bool "Harden memory copies between kernel and userspace" > - imply STRICT_DEVMEM > - help > - This option checks for obviously wrong memory regions when > - copying memory to/from the kernel (via copy_to_user() and > - copy_from_user() functions) by rejecting memory ranges that > - are larger than the specified heap object, span multiple > - separately allocated pages, are not on the process stack, > - or are part of the kernel text. This prevents entire classes > - of heap overflow exploits and similar kernel memory exposures. > - > config FORTIFY_SOURCE > bool "Harden common str/mem functions against buffer overflows" > depends on ARCH_HAS_FORTIFY_SOURCE > diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening > index c9d5ca3d8d08..00e6e2ed0c43 100644 > --- a/security/Kconfig.hardening > +++ b/security/Kconfig.hardening > @@ -279,6 +279,22 @@ config ZERO_CALL_USED_REGS > > endmenu > > +menu "String manipulation" > + > +config HARDENED_USERCOPY > + bool "Harden memory copies between kernel and userspace" > + imply STRICT_DEVMEM > + help > + This option checks for obviously wrong memory regions when > + copying memory to/from the kernel (via copy_to_user() and > + copy_from_user() functions) by rejecting memory ranges that > + are larger than the specified heap object, span multiple > + separately allocated pages, are not on the process stack, > + or are part of the kernel text. This prevents entire classes > + of heap overflow exploits and similar kernel memory exposures. > + > +endmenu > + > menu "Hardening of kernel data structures" > > config LIST_HARDENED > -- > 2.43.0 > > -- paul-moore.com
