From b92c4f922b2e8c70f8790d42e45bb9401c57be63 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Mon, 26 Mar 2007 21:32:25 -0800 Subject: [PATCH] uml: use correct register file size everywhere This patch uses MAX_REG_NR consistently to refer to the register file size. FRAME_SIZE isn't sufficient because on x86_64, it is smaller than the ptrace register file size. MAX_REG_NR was introduced as a consistent way to get the number of registers, but wasn't used everywhere it should be. When this causes a problem, it makes PTRACE_SETREGS fail on x86_64 because of a corrupted segment register value in the known-good register file. The patch also adds a register dump at that point in case there are any future problems here. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/os-Linux/sys-i386/registers.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/um/os-Linux/sys-i386') diff --git a/arch/um/os-Linux/sys-i386/registers.c b/arch/um/os-Linux/sys-i386/registers.c index 79cd93c8c5ed..84b44f9cd42a 100644 --- a/arch/um/os-Linux/sys-i386/registers.c +++ b/arch/um/os-Linux/sys-i386/registers.c @@ -15,7 +15,7 @@ /* These are set once at boot time and not changed thereafter */ -static unsigned long exec_regs[HOST_FRAME_SIZE]; +static unsigned long exec_regs[MAX_REG_NR]; static unsigned long exec_fp_regs[HOST_FP_SIZE]; static unsigned long exec_fpx_regs[HOST_XFP_SIZE]; static int have_fpx_regs = 1; @@ -101,6 +101,7 @@ void init_registers(int pid) { int err; + memset(exec_regs, 0, sizeof(exec_regs)); err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs); if(err) panic("check_ptrace : PTRACE_GETREGS failed, errno = %d", @@ -124,7 +125,7 @@ void init_registers(int pid) void get_safe_registers(unsigned long *regs, unsigned long *fp_regs) { - memcpy(regs, exec_regs, HOST_FRAME_SIZE * sizeof(unsigned long)); + memcpy(regs, exec_regs, sizeof(exec_regs)); if(fp_regs != NULL) memcpy(fp_regs, exec_fp_regs, HOST_FP_SIZE * sizeof(unsigned long)); -- cgit v1.2.3-59-g8ed1b