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 --- tools/perf/jvmti/Build | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) create mode 100644 tools/perf/jvmti/Build (limited to 'tools/perf/jvmti/Build') diff --git a/tools/perf/jvmti/Build b/tools/perf/jvmti/Build new file mode 100644 index 000000000..202cadaaf --- /dev/null +++ b/tools/perf/jvmti/Build @@ -0,0 +1,21 @@ +jvmti-y += libjvmti.o +jvmti-y += jvmti_agent.o + +# For strlcpy +jvmti-y += libstring.o libctype.o + +CFLAGS_jvmti = -fPIC -DPIC -I$(JDIR)/include -I$(JDIR)/include/linux +CFLAGS_REMOVE_jvmti = -Wmissing-declarations +CFLAGS_REMOVE_jvmti += -Wstrict-prototypes +CFLAGS_REMOVE_jvmti += -Wextra +CFLAGS_REMOVE_jvmti += -Wwrite-strings + +CFLAGS_libstring.o += -Wno-unused-parameter -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))" + +$(OUTPUT)jvmti/libstring.o: ../lib/string.c FORCE + $(call rule_mkdir) + $(call if_changed_dep,cc_o_c) + +$(OUTPUT)jvmti/libctype.o: ../lib/ctype.c FORCE + $(call rule_mkdir) + $(call if_changed_dep,cc_o_c) -- cgit v1.3.1