Commit-ID: 9bf148cb0812595bfdf5100bd2c07e9bec9c6ef5 Gitweb: http://git.kernel.org/tip/9bf148cb0812595bfdf5100bd2c07e9bec9c6ef5 Author: Colin Ian King <[email protected]> AuthorDate: Fri, 26 Feb 2016 18:55:31 +0000 Committer: Thomas Gleixner <[email protected]> CommitDate: Fri, 26 Feb 2016 22:12:47 +0100
x86/mpx: Fix off-by-one comparison with nr_registers In the unlikely event that regno == nr_registers then we get an array overrun on regoff because the invalid register check is currently off-by-one. Fix this with a check that regno is >= nr_registers instead. Detected with static analysis using CoverityScan. Fixes: fcc7ffd67991 "x86, mpx: Decode MPX instruction to get bound violation information" Signed-off-by: Colin Ian King <[email protected]> Acked-by: Dave Hansen <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: "Kirill A . Shutemov" <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]> --- arch/x86/mm/mpx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c index b2fd67d..ef05755 100644 --- a/arch/x86/mm/mpx.c +++ b/arch/x86/mm/mpx.c @@ -123,7 +123,7 @@ static int get_reg_offset(struct insn *insn, struct pt_regs *regs, break; } - if (regno > nr_registers) { + if (regno >= nr_registers) { WARN_ONCE(1, "decoded an instruction with an invalid register"); return -EINVAL; }
