diff options
author | Richard Henderson <richard.henderson@linaro.org> | 2023-08-03 17:55:28 +0000 |
---|---|---|
committer | Richard Henderson <richard.henderson@linaro.org> | 2023-08-08 13:27:17 -0700 |
commit | ad25051bae392ce35437cdf996aedecc0772af2f (patch) | |
tree | 2176d2fb97547ddf0e1873419e34d107d814384c /linux-user | |
parent | da2b71fab63f2396396021917eed9d52f33a45c0 (diff) |
linux-user: Use MAP_FIXED_NOREPLACE for initial image mmap
Use this as extra protection for the guest mapping over
any qemu host mappings.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'linux-user')
-rw-r--r-- | linux-user/elfload.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/linux-user/elfload.c b/linux-user/elfload.c index 36e4026f05..1b4bb2d5af 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -3147,8 +3147,11 @@ static void load_elf_image(const char *image_name, int image_fd, /* * Reserve address space for all of this. * - * In the case of ET_EXEC, we supply MAP_FIXED so that we get - * exactly the address range that is required. + * In the case of ET_EXEC, we supply MAP_FIXED_NOREPLACE so that we get + * exactly the address range that is required. Without reserved_va, + * the guest address space is not isolated. We have attempted to avoid + * conflict with the host program itself via probe_guest_base, but using + * MAP_FIXED_NOREPLACE instead of MAP_FIXED provides an extra check. * * Otherwise this is ET_DYN, and we are searching for a location * that can hold the memory space required. If the image is @@ -3160,7 +3163,7 @@ static void load_elf_image(const char *image_name, int image_fd, */ load_addr = target_mmap(loaddr, (size_t)hiaddr - loaddr + 1, PROT_NONE, MAP_PRIVATE | MAP_ANON | MAP_NORESERVE | - (ehdr->e_type == ET_EXEC ? MAP_FIXED : 0), + (ehdr->e_type == ET_EXEC ? MAP_FIXED_NOREPLACE : 0), -1, 0); if (load_addr == -1) { goto exit_mmap; |