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| author | Ali Ahmet Memis <ali@iusegentoo.com> | 2026-08-21 01:45:27 +0000 |
|---|---|---|
| committer | Stafford Horne <shorne@gmail.com> | 2026-08-29 07:32:26 +0100 |
| commit | 78004e9a87f240df03e2f73120d291763c32e0a7 (patch) | |
| tree | 137c22dd795222931b9d2bf2501d37cd766741aa /scripts/Makefile.ubsan | |
| download | linux-stable-78004e9a87f240df03e2f73120d291763c32e0a7.tar.gz linux-stable-78004e9a87f240df03e2f73120d291763c32e0a7.zip | |
openrisc: fix arbitrary kernel memory access via or1k_atomic syscallgrafted
sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user
pointers, v1 and v2, and swaps the words they point to in hand-written
assembly.
l.lwz r29,0(r4)
l.lwz r27,0(r5)
l.sw 0(r4),r27
l.sw 0(r5),r29
The pointers are not checked with access_ok(). The four memory
accesses also have no exception table entries.
A caller passes a kernel address as either pointer, and the syscall
reads from and writes to it directly.
This gives an unprivileged process a kernel read/write primitive. It
overwrites kernel data such as the sys_call_table, gaining code
execution in kernel context.
Check both pointers before entering the critical section. Add fixups
for the four memory accesses so faults on valid but unmapped user
addresses return -EFAULT.
[shorne@gmail.com: fix comment style]
Fixes: 9d02a4283e9c ("OpenRISC: Boot code")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Diffstat (limited to 'scripts/Makefile.ubsan')
| -rw-r--r-- | scripts/Makefile.ubsan | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan new file mode 100644 index 000000000..734a102e6 --- /dev/null +++ b/scripts/Makefile.ubsan @@ -0,0 +1,28 @@ +# SPDX-License-Identifier: GPL-2.0 + +# Shared with KVM/arm64. +export CFLAGS_UBSAN_TRAP := $(call cc-option,-fsanitize-trap=undefined,-fsanitize-undefined-trap-on-error) + +# Enable available and selected UBSAN features. +ubsan-cflags-$(CONFIG_UBSAN_ALIGNMENT) += -fsanitize=alignment +ubsan-cflags-$(CONFIG_UBSAN_BOUNDS_STRICT) += -fsanitize=bounds-strict +ubsan-cflags-$(CONFIG_UBSAN_ARRAY_BOUNDS) += -fsanitize=array-bounds +ubsan-cflags-$(CONFIG_UBSAN_LOCAL_BOUNDS) += -fsanitize=local-bounds +ubsan-cflags-$(CONFIG_UBSAN_SHIFT) += -fsanitize=shift +ubsan-cflags-$(CONFIG_UBSAN_DIV_ZERO) += -fsanitize=integer-divide-by-zero +ubsan-cflags-$(CONFIG_UBSAN_UNREACHABLE) += -fsanitize=unreachable +ubsan-cflags-$(CONFIG_UBSAN_BOOL) += -fsanitize=bool +ubsan-cflags-$(CONFIG_UBSAN_ENUM) += -fsanitize=enum +ubsan-cflags-$(CONFIG_UBSAN_TRAP) += $(CFLAGS_UBSAN_TRAP) + +export CFLAGS_UBSAN := $(ubsan-cflags-y) + +ubsan-integer-wrap-cflags-$(CONFIG_UBSAN_INTEGER_WRAP) += \ + -DINTEGER_WRAP \ + -fsanitize-undefined-ignore-overflow-pattern=all \ + -fsanitize=signed-integer-overflow \ + -fsanitize=unsigned-integer-overflow \ + -fsanitize=implicit-signed-integer-truncation \ + -fsanitize=implicit-unsigned-integer-truncation \ + -fsanitize-ignorelist=$(srctree)/scripts/integer-wrap-ignore.scl +export CFLAGS_UBSAN_INTEGER_WRAP := $(ubsan-integer-wrap-cflags-y) |