linux-user: Check for bad event numbers in epoll_wait

The kernel checks that the maxevents parameter to epoll_wait
is non-negative and not larger than EP_MAX_EVENTS. Add this
check to our implementation, so that:
 * we fail these cases EINVAL rather than EFAULT
 * we don't pass negative or overflowing values to the
   lock_user() size calculation

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
This commit is contained in:
Peter Maydell 2016-07-18 15:35:59 +01:00 committed by Riku Voipio
parent 700fa58e4b
commit 2ba7fae3bd
2 changed files with 8 additions and 0 deletions

View file

@ -2585,6 +2585,9 @@ struct target_epoll_event {
abi_uint events;
target_epoll_data_t data;
} TARGET_EPOLL_PACKED;
#define TARGET_EP_MAX_EVENTS (INT_MAX / sizeof(struct target_epoll_event))
#endif
struct target_rlimit64 {
uint64_t rlim_cur;