From: Jason Wessel Date: Thu, 5 Aug 2010 14:22:22 +0000 (-0500) Subject: gdbstub: do not directly use dbg_reg_def[] in gdb_cmd_reg_set() X-Git-Tag: firefly_0821_release~9833^2~1277^2~9 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6d855b1d83c980c1283d98d2d63a2bd3a87e21b7;p=firefly-linux-kernel-4.4.55.git gdbstub: do not directly use dbg_reg_def[] in gdb_cmd_reg_set() Presently the usable registers definitions on x86 are not contiguous for kgdb. The x86 kgdb uses a case statement for the sparse register accesses. The array which defines the registers (dbg_reg_def) should not be used directly in order to safely work with sparse register definitions. Specifically there was a problem when gdb accesses ORIG_AX, which is accessed only through the case statement. This patch encodes register memory using the size information provided from the debugger which avoids the need to look up the size of the register. The dbg_set_reg() function always further validates the inputs from the debugger. Signed-off-by: Jason Wessel Signed-off-by: Dongdong Deng --- diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c index 4ef9dddf4588..fc7b174c4718 100644 --- a/kernel/debug/gdbstub.c +++ b/kernel/debug/gdbstub.c @@ -604,6 +604,7 @@ static void gdb_cmd_reg_set(struct kgdb_state *ks) { unsigned long regnum; char *ptr = &remcom_in_buffer[1]; + int i = 0; kgdb_hex2long(&ptr, ®num); if (*ptr++ != '=' || @@ -612,7 +613,14 @@ static void gdb_cmd_reg_set(struct kgdb_state *ks) error_packet(remcom_out_buffer, -EINVAL); return; } - kgdb_hex2mem(ptr, (char *)gdb_regs, dbg_reg_def[regnum].size); + memset(gdb_regs, 0, sizeof(gdb_regs)); + while (i < sizeof(gdb_regs) * 2) + if (hex_to_bin(ptr[i]) >= 0) + i++; + else + break; + i = i / 2; + kgdb_hex2mem(ptr, (char *)gdb_regs, i); dbg_set_reg(regnum, gdb_regs, ks->linux_regs); strcpy(remcom_out_buffer, "OK"); }