Commit-ID: 9006a01829a50cfd6bbd4980910ed46e895e93d7 Gitweb: http://git.kernel.org/tip/9006a01829a50cfd6bbd4980910ed46e895e93d7 Author: Marc Zyngier <marc.zyngier@xxxxxxx> AuthorDate: Fri, 15 Jan 2016 17:41:09 +0000 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitDate: Wed, 27 Jan 2016 12:38:04 +0100 hrtimer: Catch illegal clockids It is way too easy to take any random clockid and feed it to the hrtimer subsystem. At best, it gets mapped to a monotonic base, but it would be better to just catch illegal values as early as possible. This patch does exactly that, mapping illegal clockids to an illegal base index, and panicing when we detect the illegal condition. Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> Cc: Tomasz Nowicki <tn@xxxxxxxxxxxx> Cc: Christoffer Dall <christoffer.dall@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1452879670-16133-3-git-send-email-marc.zyngier@xxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> --- kernel/time/hrtimer.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index a125f22..cb0fe70 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -99,6 +99,9 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = }; static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = { + /* Make sure we catch unsupported clockids */ + [0 ... MAX_CLOCKS - 1] = HRTIMER_MAX_CLOCK_BASES, + [CLOCK_REALTIME] = HRTIMER_BASE_REALTIME, [CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC, [CLOCK_MONOTONIC_RAW] = HRTIMER_BASE_MONOTONIC_RAW, @@ -108,7 +111,9 @@ static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = { static inline int hrtimer_clockid_to_base(clockid_t clock_id) { - return hrtimer_clock_to_base_table[clock_id]; + int base = hrtimer_clock_to_base_table[clock_id]; + BUG_ON(base == HRTIMER_MAX_CLOCK_BASES); + return base; } /* -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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