From 0acd4ab849827bbc20402e01c9da088207c0d236 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?R=C3=A9mi=20Denis-Courmont?= Date: Thu, 4 Jul 2019 10:41:15 +0200 Subject: [PATCH] linux-user: check valid address in access_ok() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fix a crash with LTP testsuite and aarch64: tst_test.c:1015: INFO: Timeout per run is 0h 05m 00s qemu-aarch64: .../qemu/accel/tcg/translate-all.c:2522: page_check_range: Assertion `start < ((target_ulong)1 << L1_MAP_ADDR_SPACE_BITS)' failed. qemu:handle_cpu_signal received signal outside vCPU context @ pc=0x60001554 page_check_range() should never be called with address outside the guest address space. This patch adds a guest_addr_valid() check in access_ok() to only call page_check_range() with a valid address. Fixes: f6768aa1b4c6 ("target/arm: fix AArch64 virtual address space size") Signed-off-by: Rémi Denis-Courmont Signed-off-by: Laurent Vivier Message-Id: <20190704084115.24713-1-lvivier@redhat.com> Signed-off-by: Laurent Vivier --- include/exec/cpu_ldst.h | 4 ++++ linux-user/qemu.h | 4 +++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/include/exec/cpu_ldst.h b/include/exec/cpu_ldst.h index 9de8c93303..9151fdb042 100644 --- a/include/exec/cpu_ldst.h +++ b/include/exec/cpu_ldst.h @@ -62,7 +62,11 @@ typedef uint64_t abi_ptr; /* All direct uses of g2h and h2g need to go away for usermode softmmu. */ #define g2h(x) ((void *)((unsigned long)(abi_ptr)(x) + guest_base)) +#if HOST_LONG_BITS <= TARGET_VIRT_ADDR_SPACE_BITS +#define guest_addr_valid(x) (1) +#else #define guest_addr_valid(x) ((x) <= GUEST_ADDR_MAX) +#endif #define h2g_valid(x) guest_addr_valid((unsigned long)(x) - guest_base) static inline int guest_range_valid(unsigned long start, unsigned long len) diff --git a/linux-user/qemu.h b/linux-user/qemu.h index fab287b7ec..4258e4162d 100644 --- a/linux-user/qemu.h +++ b/linux-user/qemu.h @@ -456,7 +456,9 @@ extern unsigned long guest_stack_size; static inline int access_ok(int type, abi_ulong addr, abi_ulong size) { - return page_check_range((target_ulong)addr, size, + return guest_addr_valid(addr) && + (size == 0 || guest_addr_valid(addr + size - 1)) && + page_check_range((target_ulong)addr, size, (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0; }