From 0c710050c47d45eb77b28c271cddefc5c785cb40 Mon Sep 17 00:00:00 2001 From: Zhe Qiao Date: Wed, 31 Jul 2024 16:45:47 +0800 Subject: [PATCH] riscv/mm: Add handling for VM_FAULT_SIGSEGV in mm_fault_error() Handle VM_FAULT_SIGSEGV in the page fault path so that we correctly kill the process and we don't BUG() the kernel. Fixes: 07037db5d479 ("RISC-V: Paging and MMU") Signed-off-by: Zhe Qiao Reviewed-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20240731084547.85380-1-qiaozhe@iscas.ac.cn Signed-off-by: Palmer Dabbelt --- arch/riscv/mm/fault.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c index 5224f3733802..a9f2b4af8f3f 100644 --- a/arch/riscv/mm/fault.c +++ b/arch/riscv/mm/fault.c @@ -61,26 +61,27 @@ static inline void no_context(struct pt_regs *regs, unsigned long addr) static inline void mm_fault_error(struct pt_regs *regs, unsigned long addr, vm_fault_t fault) { + if (!user_mode(regs)) { + no_context(regs, addr); + return; + } + if (fault & VM_FAULT_OOM) { /* * We ran out of memory, call the OOM killer, and return the userspace * (which will retry the fault, or kill us if we got oom-killed). */ - if (!user_mode(regs)) { - no_context(regs, addr); - return; - } pagefault_out_of_memory(); return; } else if (fault & (VM_FAULT_SIGBUS | VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE)) { /* Kernel mode? Handle exceptions or die */ - if (!user_mode(regs)) { - no_context(regs, addr); - return; - } do_trap(regs, SIGBUS, BUS_ADRERR, addr); return; + } else if (fault & VM_FAULT_SIGSEGV) { + do_trap(regs, SIGSEGV, SEGV_MAPERR, addr); + return; } + BUG(); } -- 2.25.1