Check return value of copy_to_user in compat_sys_pselect7 Fix linux/fs/compat.c: In function compat_sys_pselect7 linux/fs/compat.c:1869: warning: ignoring return value of copy_to_user, declared with attribute warn_unused_result To make it easier to handle I changed to semantics to not try to write out a timespec if an error occurred. I hope that's ok. Cc: dwmw2@infradead.org Signed-off-by: Andi Kleen --- fs/compat.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) Index: linux/fs/compat.c =================================================================== --- linux.orig/fs/compat.c +++ linux/fs/compat.c @@ -1855,7 +1855,7 @@ asmlinkage long compat_sys_pselect7(int } while (!ret && !timeout && tsp && (ts.tv_sec || ts.tv_nsec)); - if (tsp && !(current->personality & STICKY_TIMEOUTS)) { + if (ret == 0 && tsp && !(current->personality & STICKY_TIMEOUTS)) { struct compat_timespec rts; rts.tv_sec = timeout / HZ; @@ -1866,7 +1866,8 @@ asmlinkage long compat_sys_pselect7(int } if (compat_timespec_compare(&rts, &ts) >= 0) rts = ts; - copy_to_user(tsp, &rts, sizeof(rts)); + if (copy_to_user(tsp, &rts, sizeof(rts))) + ret = -EFAULT; } if (ret == -ERESTARTNOHAND) {