I've slightly re-organised the check to more closely match the sequence that the kernel uses in do_mmap(). We check for both the zero case (EINVAL) and the overflow length case (ENOMEM).
Signed-off-by: Alex Bennée <alex.ben...@linaro.org> Cc: umarcor <1783...@bugs.launchpad.net> --- v2 - add comment on overflow --- linux-user/mmap.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/linux-user/mmap.c b/linux-user/mmap.c index d0c50e4888..41e0983ce8 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -391,14 +391,23 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int prot, } #endif - if (offset & ~TARGET_PAGE_MASK) { + if (!len) { errno = EINVAL; goto fail; } + /* Also check for overflows... */ len = TARGET_PAGE_ALIGN(len); - if (len == 0) - goto the_end; + if (!len) { + errno = ENOMEM; + goto fail; + } + + if (offset & ~TARGET_PAGE_MASK) { + errno = EINVAL; + goto fail; + } + real_start = start & qemu_host_page_mask; host_offset = offset & qemu_host_page_mask; -- 2.17.1 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1783362 Title: qemu-user: mmap should return failure (MAP_FAILED, -1) instead of success (NULL, 0) when len==0 To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1783362/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs