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Eugeniy Paltsev authored
commit a8c715b4 upstream. As of today if userspace process tries to access a kernel virtual addres (0x7000_0000 to 0x7ffff_ffff) such that a legit kernel mapping already exists, that process hangs instead of being killed with SIGSEGV Fix that by ensuring that do_page_fault() handles kenrel vaddr only if in kernel mode. And given this, we can also simplify the code a bit. Now a vmalloc fault implies kernel mode so its failure (for some reason) can reuse the @no_context label and we can remove @bad_area_nosemaphore. Reproduce user test for original problem: ------------------------>8----------------- #include <stdlib.h> #include <stdint.h> int main(int argc, char *argv[]) { volatile uint32_t temp; temp = *(uint32_t *)(0x70000000); } ------------------------>8----------------- Cc: <stable@vger.kernel.org> Signed-off-by:
Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by:
Vineet Gupta <vgupta@synopsys.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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