Commit 8c98a605 authored by Borislav Petkov's avatar Borislav Petkov
Browse files

perf/x86/intel/ds: Check return values of insn decoder functions 



branch_type() doesn't need to call the full insn_decode() because it
doesn't need it in all cases thus leave the calls separate.

Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-9-bp@alien8.de
parent 2ff49881

arch/x86/events/intel/lbr.c

+5 −5
Original line number Diff line number Diff line
@@ -1224,8 +1224,7 @@ static int branch_type(unsigned long from, unsigned long to, int abort) 
	is64 = kernel_ip((unsigned long)addr) || any_64bit_mode(current_pt_regs());

#endif

	insn_init(&insn, addr, bytes_read, is64);

	insn_get_opcode(&insn);

	if (!insn.opcode.got)

	if (insn_get_opcode(&insn))

		return X86_BR_ABORT;



	switch (insn.opcode.bytes[0]) {
@@ -1262,8 +1261,7 @@ static int branch_type(unsigned long from, unsigned long to, int abort) 
		ret = X86_BR_INT;

		break;

	case 0xe8: /* call near rel */

		insn_get_immediate(&insn);

		if (insn.immediate1.value == 0) {

		if (insn_get_immediate(&insn) || insn.immediate1.value == 0) {

			/* zero length call */

			ret = X86_BR_ZERO_CALL;

			break;
@@ -1279,7 +1277,9 @@ static int branch_type(unsigned long from, unsigned long to, int abort) 
		ret = X86_BR_JMP;

		break;

	case 0xff: /* call near absolute, call far absolute ind */

		insn_get_modrm(&insn);

		if (insn_get_modrm(&insn))

			return X86_BR_ABORT;



		ext = (insn.modrm.bytes[0] >> 3) & 0x7;

		switch (ext) {

		case 2: /* near ind call */