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-rw-r--r--arch/powerpc/mm/fault.c28
1 files changed, 13 insertions, 15 deletions
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 04505f938bbc..389a2a875262 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -210,28 +210,26 @@ static bool bad_kernel_fault(struct pt_regs *regs, unsigned long error_code,
return true;
}
- if (!is_exec && address < TASK_SIZE && (error_code & (DSISR_PROTFAULT | DSISR_KEYFAULT)) &&
- !search_exception_tables(regs->nip)) {
- pr_crit_ratelimited("Kernel attempted to access user page (%lx) - exploit attempt? (uid: %d)\n",
- address,
- from_kuid(&init_user_ns, current_uid()));
- }
-
// Kernel fault on kernel address is bad
if (address >= TASK_SIZE)
return true;
- // Fault on user outside of certain regions (eg. copy_tofrom_user()) is bad
- if (!search_exception_tables(regs->nip))
- return true;
+ // Read/write fault blocked by KUAP is bad, it can never succeed.
+ if (bad_kuap_fault(regs, address, is_write)) {
+ pr_crit_ratelimited("Kernel attempted to %s user page (%lx) - exploit attempt? (uid: %d)\n",
+ is_write ? "write" : "read", address,
+ from_kuid(&init_user_ns, current_uid()));
+
+ // Fault on user outside of certain regions (eg. copy_tofrom_user()) is bad
+ if (!search_exception_tables(regs->nip))
+ return true;
- // Read/write fault in a valid region (the exception table search passed
- // above), but blocked by KUAP is bad, it can never succeed.
- if (bad_kuap_fault(regs, address, is_write))
+ // Read/write fault in a valid region (the exception table search passed
+ // above), but blocked by KUAP is bad, it can never succeed.
return WARN(true, "Bug: %s fault blocked by KUAP!", is_write ? "Write" : "Read");
+ }
- // What's left? Kernel fault on user in well defined regions (extable
- // matched), and allowed by KUAP in the faulting context.
+ // What's left? Kernel fault on user and allowed by KUAP in the faulting context.
return false;
}