Commit-ID: 5e5aeb4367b450a28f447f6d5ab57d8f2ab16a5f Gitweb: http://git.kernel.org/tip/5e5aeb4367b450a28f447f6d5ab57d8f2ab16a5f Author: Sasha Levin <[email protected]> AuthorDate: Wed, 3 Dec 2014 19:25:05 -0500 Committer: John Stultz <[email protected]> CommitDate: Wed, 7 Jan 2015 09:50:32 -0800
time: adjtimex: Validate the ADJ_FREQUENCY values Verify that the frequency value from userspace is valid and makes sense. Unverified values can cause overflows later on. Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: stable <[email protected]> Signed-off-by: Sasha Levin <[email protected]> [jstultz: Fix up bug for negative values and drop redunent cap check] Signed-off-by: John Stultz <[email protected]> --- kernel/time/ntp.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 87a346f..28bf91c 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -633,6 +633,13 @@ int ntp_validate_timex(struct timex *txc) if ((txc->modes & ADJ_SETOFFSET) && (!capable(CAP_SYS_TIME))) return -EPERM; + if (txc->modes & ADJ_FREQUENCY) { + if (LONG_MIN / PPM_SCALE > txc->freq) + return -EINVAL; + if (LONG_MAX / PPM_SCALE < txc->freq) + return -EINVAL; + } + return 0; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
