diff options
| author | Richard Purdie <richard.purdie@linuxfoundation.org> | 2021-01-08 17:42:12 +0000 |
|---|---|---|
| committer | Laurent Vivier <laurent@vivier.eu> | 2021-02-13 22:50:50 +0100 |
| commit | ccc5ccc17f8cfbfd87d9aede5d12a2d47c56e712 (patch) | |
| tree | 47efe65cf5f2e3fb15aba79ed2ac864dbb07fce4 /linux-user | |
| parent | 22d113b52f410d345c3a50a00d2eafa64138e427 (diff) | |
linux-user/mmap: Avoid asserts for out of range mremap calls
If mremap() is called without the MREMAP_MAYMOVE flag with a start address
just before the end of memory (reserved_va) where new_size would exceed
it (and GUEST_ADDR_MAX), the assert(end - 1 <= GUEST_ADDR_MAX) in
page_set_flags() would trigger.
Add an extra guard to the guest_range_valid() checks to prevent this and
avoid asserting binaries when reserved_va is set.
This meant a bug I was seeing locally now gives the same behaviour
regardless of whether reserved_va is set or not.
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <70c46e7b999bafbb01d54bfafd44b420d0b782e9.camel@linuxfoundation.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Diffstat (limited to 'linux-user')
| -rw-r--r-- | linux-user/mmap.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 810653c503..1c9faef476 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -724,7 +724,9 @@ abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size, if (!guest_range_valid(old_addr, old_size) || ((flags & MREMAP_FIXED) && - !guest_range_valid(new_addr, new_size))) { + !guest_range_valid(new_addr, new_size)) || + ((flags & MREMAP_MAYMOVE) == 0 && + !guest_range_valid(old_addr, new_size))) { errno = ENOMEM; return -1; } |