Merge tag 'printk-for-5.2-fixes' of... (e290e6af) · Commits · 戴 / test

Merge tag 'printk-for-5.2-fixes' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk fixup from Petr Mladek: "Replace the problematic probe_kernel_read() with original simple pointer checks in vsprintf()" * tag 'printk-for-5.2-fixes' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: vsprintf: Do not break early boot with probing addresses

lib/vsprintf.c

+4 −7

Original line number	Diff line number	Diff line
		@@ -628,19 +628,16 @@ static char error_string(char buf, char end, const char s,
		}

		/*
		* This is not a fool-proof test. 99% of the time that this will fault is
		* due to a bad pointer, not one that crosses into bad memory. Just test
		* the address to make sure it doesn't fault due to a poorly added printk
		* during debugging.
		* Do not call any complex external code here. Nested printk()/vsprintf()
		* might cause infinite loops. Failures might break printk() and would
		* be hard to debug.
		*/
		static const char check_pointer_msg(const void ptr)
		{
		char byte;

		if (!ptr)
		return "(null)";

		if (probe_kernel_address(ptr, byte))
		if ((unsigned long)ptr < PAGE_SIZE \|\| IS_ERR_VALUE(ptr))
		return "(efault)";

		return NULL;