Le 26/07/2018 à 19:58, Alex Bennée a écrit : > > Laurent Vivier <[email protected]> writes: > >> Le 26/07/2018 à 15:29, Alex Bennée a écrit: >>> I've slightly re-organised the check to more closely match the >>> sequence that the kernel uses in do_mmap(). >>> >>> Signed-off-by: Alex Bennée <[email protected]> >>> Cc: umarcor <[email protected]> >>> --- >>> linux-user/mmap.c | 14 +++++++++++--- >>> 1 file changed, 11 insertions(+), 3 deletions(-) >>> >>> diff --git a/linux-user/mmap.c b/linux-user/mmap.c >>> index d0c50e4888..3ef69fa2d0 100644 >>> --- a/linux-user/mmap.c >>> +++ b/linux-user/mmap.c >>> @@ -391,14 +391,22 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, >>> int prot, >>> } >>> #endif >>> >>> - if (offset & ~TARGET_PAGE_MASK) { >>> + if (!len) { >>> errno = EINVAL; >>> goto fail; >>> } >>> >>> len = TARGET_PAGE_ALIGN(len); >>> - if (len == 0) >>> - goto the_end; >>> + if (!len) { >>> + errno = EINVAL; >>> + goto fail; >>> + } >> >> Why do you check twice len? >> TARGET_PAGE_ALIGN() rounds up the value, so if it was not 0, it cannot >> be now. > > I was trying to follow the kernel style but I realise TARGET_PAGE_ALIGN > might be a different test compared to the kernel's PAGE_ALIGN(len) for > overflows: ... > /* Careful about overflows.. */ > len = PAGE_ALIGN(len); > if (!len) > return -ENOMEM; >
OK, so keep it but you should use ENOMEM, not EINVAL (and add a comment :) ) Thanks, Laurent -- 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 [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
