From 8633e74002cd48a0842c6147978184dfe1787926 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Wed, 13 Dec 2023 14:40:26 +0100 Subject: [PATCH] riscv: Fix module_alloc() that did not reset the linear mapping permissions [ Upstream commit 749b94b08005929bbc636df21a23322733166e35 ] After unloading a module, we must reset the linear mapping permissions, see the example below: Before unloading a module: 0xffffaf809d65d000-0xffffaf809d6dc000 0x000000011d65d000 508K PTE . .. .. D A G . . W R V 0xffffaf809d6dc000-0xffffaf809d6dd000 0x000000011d6dc000 4K PTE . .. .. D A G . . . R V 0xffffaf809d6dd000-0xffffaf809d6e1000 0x000000011d6dd000 16K PTE . .. .. D A G . . W R V 0xffffaf809d6e1000-0xffffaf809d6e7000 0x000000011d6e1000 24K PTE . .. .. D A G . X . R V After unloading a module: 0xffffaf809d65d000-0xffffaf809d6e1000 0x000000011d65d000 528K PTE . .. .. D A G . . W R V 0xffffaf809d6e1000-0xffffaf809d6e7000 0x000000011d6e1000 24K PTE . .. .. D A G . X W R V The last mapping is not reset and we end up with WX mappings in the linear mapping. So add VM_FLUSH_RESET_PERMS to our module_alloc() definition. Fixes: 0cff8bff7af8 ("riscv: avoid the PIC offset of static percpu data in module beyond 2G limits") Signed-off-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20231213134027.155327-2-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin --- arch/riscv/kernel/module.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c index 7c651d5..df4f6fe 100644 --- a/arch/riscv/kernel/module.c +++ b/arch/riscv/kernel/module.c @@ -440,7 +440,8 @@ void *module_alloc(unsigned long size) { return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, GFP_KERNEL, - PAGE_KERNEL, 0, NUMA_NO_NODE, + PAGE_KERNEL, VM_FLUSH_RESET_PERMS, + NUMA_NO_NODE, __builtin_return_address(0)); } #endif -- 2.7.4