diff options
| author | Maximilian Riemensberger <riemensberger@cadami.net> | 2018-01-07 01:01:44 +0000 |
|---|---|---|
| committer | Laurent Vivier <laurent@vivier.eu> | 2018-01-23 14:20:52 +0100 |
| commit | 95e6d4305affbbf5258c6a533be9bfd24599da90 (patch) | |
| tree | 69f43fca0ef20746517d23ae334ee9ac948d64a2 /linux-user/mmap.c | |
| parent | 10fa993aae539fa8d0da1da17169e05f1dfb4f95 (diff) | |
linux-user/mmap.c: Avoid choosing NULL as start address
mmap() is required by the linux kernel ABI and POSIX to return a
non-NULL address when the implementation chooses a start address for the
mapping.
The current implementation of mmap_find_vma_reserved() can return NULL
as start address of a mapping which leads to subsequent crashes inside
the guests glibc, e.g. output of qemu-arm-static --strace executing a
test binary stx_test:
1879 mmap2(NULL,8388608,PROT_READ|PROT_WRITE,MAP_PRIVATE|MAP_ANONYMOUS|0x20000,-1,0) = 0x00000000
1879 write(2,0xf6fd39d0,79) stx_test: allocatestack.c:514: allocate_stack: Assertion `mem != NULL' failed.
This patch fixes mmap_find_vma_reserved() by skipping NULL as start
address while searching for a suitable mapping start address.
CC: Riku Voipio <riku.voipio@iki.fi>
CC: Laurent Vivier <laurent@vivier.eu>
CC: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Maximilian Riemensberger <riemensberger@cadami.net>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <1515286904-86418-1-git-send-email-riemensberger@cadami.net>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Diffstat (limited to 'linux-user/mmap.c')
| -rw-r--r-- | linux-user/mmap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 4888f53139..0fbfd6dff2 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -234,7 +234,7 @@ static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size) if (prot) { end_addr = addr; } - if (addr + size == end_addr) { + if (addr && addr + size == end_addr) { break; } addr -= qemu_host_page_size; |