quota: Fix quota corruption with generic/232 test

[sfrench/cifs-2.6.git] / fs / fcntl.c

diff --git a/fs/fcntl.c b/fs/fcntl.c
index 3b01b646e528e189b57a1876abf2d4f13364a1bb..0491da3b28c36bbf786f1f1303d3bb44f6bfdb98 100644 (file)
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -741,10 +741,21 @@ static void send_sigio_to_task(struct task_struct *p,
                        si.si_signo = signum;
                        si.si_errno = 0;
                        si.si_code  = reason;
+                       /*
+                        * Posix definies POLL_IN and friends to be signal
+                        * specific si_codes for SIG_POLL.  Linux extended
+                        * these si_codes to other signals in a way that is
+                        * ambiguous if other signals also have signal
+                        * specific si_codes.  In that case use SI_SIGIO instead
+                        * to remove the ambiguity.
+                        */
+                       if (sig_specific_sicodes(signum))
+                               si.si_code = SI_SIGIO;
+
                        /* Make sure we are called with one of the POLL_*
                           reasons, otherwise we could leak kernel stack into
                           userspace.  */
-                       BUG_ON((reason & __SI_MASK) != __SI_POLL);
+                       BUG_ON((reason < POLL_IN) || ((reason - POLL_IN) >= NSIGPOLL));
                        if (reason - POLL_IN >= NSIGPOLL)
                                si.si_band  = ~0L;
                        else