5.15-stable review patch. If anyone has any objections, please let me know.
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From: Zhe Qiao qiaozhe@iscas.ac.cn
[ Upstream commit 0c710050c47d45eb77b28c271cddefc5c785cb40 ]
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 qiaozhe@iscas.ac.cn Reviewed-by: Alexandre Ghiti alexghiti@rivosinc.com Link: https://lore.kernel.org/r/20240731084547.85380-1-qiaozhe@iscas.ac.cn Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 884a3c76573cf..3fc62e05bac11 100644 --- a/arch/riscv/mm/fault.c +++ b/arch/riscv/mm/fault.c @@ -60,26 +60,27 @@ 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) { /* 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(); }