|author||Stephen Kitt <firstname.lastname@example.org>||2021-11-05 13:45:18 -0700|
|committer||Linus Torvalds <email@example.com>||2021-11-06 13:30:43 -0700|
mm: remove HARDENED_USERCOPY_FALLBACK
This has served its purpose and is no longer used. All usercopy violations appear to have been handled by now, any remaining instances (or new bugs) will cause copies to be rejected. This isn't a direct revert of commit 2d891fbc3bb6 ("usercopy: Allow strict enforcement of whitelists"); since usercopy_fallback is effectively 0, the fallback handling is removed too. This also removes the usercopy_fallback module parameter on slab_common. Link: https://github.com/KSPP/linux/issues/153 Link: https://firstname.lastname@example.org Signed-off-by: Stephen Kitt <email@example.com> Suggested-by: Kees Cook <firstname.lastname@example.org> Acked-by: Kees Cook <email@example.com> Reviewed-by: Joel Stanley <firstname.lastname@example.org> [defconfig change] Acked-by: David Rientjes <email@example.com> Cc: Christoph Lameter <firstname.lastname@example.org> Cc: Pekka Enberg <email@example.com> Cc: Joonsoo Kim <firstname.lastname@example.org> Cc: Vlastimil Babka <email@example.com> Cc: James Morris <firstname.lastname@example.org> Cc: "Serge E . Hallyn" <email@example.com> Signed-off-by: Andrew Morton <firstname.lastname@example.org> Signed-off-by: Linus Torvalds <email@example.com>
Diffstat (limited to 'security')
1 files changed, 0 insertions, 14 deletions
diff --git a/security/Kconfig b/security/Kconfig
index 0ced7fd33e4d..d9698900c9b7 100644
@@ -163,20 +163,6 @@ config HARDENED_USERCOPY
or are part of the kernel text. This kills entire classes
of heap overflow exploits and similar kernel memory exposures.
- bool "Allow usercopy whitelist violations to fallback to object size"
- depends on HARDENED_USERCOPY
- default y
- This is a temporary option that allows missing usercopy whitelists
- to be discovered via a WARN() to the kernel log, instead of
- rejecting the copy, falling back to non-whitelisted hardened
- usercopy that checks the slab allocation size instead of the
- whitelist size. This option will be removed once it seems like
- all missing usercopy whitelists have been identified and fixed.
- Booting with "slab_common.usercopy_fallback=Y/N" can change
- this setting.
bool "Refuse to copy allocations that span multiple pages"
depends on HARDENED_USERCOPY