From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall 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 Signed-off-by: Stafford Horne --- fs/unicode/Makefile | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 fs/unicode/Makefile (limited to 'fs/unicode/Makefile') diff --git a/fs/unicode/Makefile b/fs/unicode/Makefile new file mode 100644 index 000000000..d95be7fb9 --- /dev/null +++ b/fs/unicode/Makefile @@ -0,0 +1,41 @@ +# SPDX-License-Identifier: GPL-2.0 + +ifneq ($(CONFIG_UNICODE),) +obj-y += unicode.o +endif +obj-$(CONFIG_UNICODE) += utf8data.o +obj-$(CONFIG_UNICODE_NORMALIZATION_KUNIT_TEST) += tests/utf8_kunit.o + +unicode-y := utf8-norm.o utf8-core.o + +$(obj)/utf8-data.o: $(obj)/utf8data.c + +# In the normal build, the checked-in utf8data.c is just shipped. +# +# To generate utf8data.c from UCD, put *.txt files in this directory +# and pass REGENERATE_UTF8DATA=1 from the command line. +ifdef REGENERATE_UTF8DATA + +quiet_cmd_utf8data = GEN $@ + cmd_utf8data = $< \ + -a $(src)/DerivedAge.txt \ + -c $(src)/DerivedCombiningClass.txt \ + -p $(src)/DerivedCoreProperties.txt \ + -d $(src)/UnicodeData.txt \ + -f $(src)/CaseFolding.txt \ + -n $(src)/NormalizationCorrections.txt \ + -t $(src)/NormalizationTest.txt \ + -o $@ + +$(obj)/utf8data.c: $(obj)/mkutf8data $(filter %.txt, $(cmd_utf8data)) FORCE + $(call if_changed,utf8data) + +else + +$(obj)/utf8data.c: $(src)/utf8data.c_shipped FORCE + $(call if_changed,copy) + +endif + +targets += utf8data.c +hostprogs += mkutf8data -- cgit v1.3.1