Commit 7c15f41e authored Jun 30, 2019 by Linus Torvalds

Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull SMP fixes from Thomas Gleixner:
 "Two small changes for the cpu hotplug code:

   - Prevent out of bounds access which actually might crash the machine
     caused by a missing bounds check in the fail injection code

   - Warn about unsupported migitation mode command line arguments to
     make people aware that they typoed the paramater. Not necessarily a
     fix but quite some people tripped over that"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Fix out-of-bounds read when setting fail state
  cpu/speculation: Warn on unsupported mitigations= parameter

parents 72825454 33d4a5a7

kernel/cpu.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -1964,6 +1964,9 @@ static ssize_t write_cpuhp_fail(struct device *dev,
		if (ret)
		return ret;

		if (fail < CPUHP_OFFLINE \|\| fail > CPUHP_ONLINE)
		return -EINVAL;

		/*
		* Cannot fail STARTING/DYING callbacks.
		*/
		@@ -2339,6 +2342,9 @@ static int __init mitigations_parse_cmdline(char *arg)
		cpu_mitigations = CPU_MITIGATIONS_AUTO;
		else if (!strcmp(arg, "auto,nosmt"))
		cpu_mitigations = CPU_MITIGATIONS_AUTO_NOSMT;
		else
		pr_crit("Unsupported mitigations=%s, system may still be vulnerable\n",
		arg);

		return 0;
		}

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