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: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-9-bp@alien8.de

diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c
index 21890dacfcfee5f7406e5ac5b72980188ccb3997..9ecf5028fb8fa36ce573f517222f8126f7b43646 100644 (file)
--- a/arch/x86/events/intel/lbr.c
+++ b/arch/x86/events/intel/lbr.c
@@ -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 */