This is a note to let you know that I've just added the patch titled x86/mpx: Fix off-by-one comparison with nr_registers to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-mpx-fix-off-by-one-comparison-with-nr_registers.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 9bf148cb0812595bfdf5100bd2c07e9bec9c6ef5 Mon Sep 17 00:00:00 2001 From: Colin Ian King <colin.king@xxxxxxxxxxxxx> Date: Fri, 26 Feb 2016 18:55:31 +0000 Subject: x86/mpx: Fix off-by-one comparison with nr_registers From: Colin Ian King <colin.king@xxxxxxxxxxxxx> commit 9bf148cb0812595bfdf5100bd2c07e9bec9c6ef5 upstream. 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 <colin.king@xxxxxxxxxxxxx> Acked-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: "Kirill A . Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1456512931-3388-1-git-send-email-colin.king@xxxxxxxxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c index b2fd67da1701..ef05755a1900 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; } Patches currently in stable-queue which might be from colin.king@xxxxxxxxxxxxx are queue-4.4/x86-mpx-fix-off-by-one-comparison-with-nr_registers.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html