Attachment 117194 Details for Bug 91316 – os: Fix upper bound for looping over fd_set.fd_mask[]

[patch] os: Fix upper bound for looping over fd_set.fd_mask[]

0001-os-Fix-upper-bound-for-looping-over-fd_set.fd_mask.patch (text/plain), 3.57 KB, created by Chris Wilson on 2015-07-17 10:17:49 UTC

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Creator: Chris Wilson

Created: 2015-07-17 10:17:49 UTC

Size: 3.57 KB

patch

obsolete

>From 2bcf09ff895b9a8786cc63acef499002a97143d5 Mon Sep 17 00:00:00 2001
>From: Chris Wilson <chris@chris-wilson.co.uk>
>Date: Fri, 17 Jul 2015 10:59:01 +0100
>Subject: [PATCH] os: Fix upper bound for looping over fd_set.fd_mask[]
>
>When x11proto was seemingly changed to allow for more file descriptors
>(and more Clients) by increasing XFD_SETSIZE in
>
>commit 2c94cdb453bc641246cc8b9a876da9799bee1ce7
>Author: Olivier Fourdan <ofourdan@redhat.com>
>Date:   Fri May 29 18:16:34 2015 +0200
>
>    Increase the number of file descriptors
>
>    To allow up to 512 clients, the number of file descriptors being
>    monitored need to be increased accordingly.
>
>the actual fd_set.fd_mask[] was not increased as that is defined in
>terms of FD_SETSIZE and is used by all iterators inside Xpoll.h.
>
>X however does iterate over XFD_SETSIZE instead. The result being that
>we increased the upper bound without increasing the array size with the
>result we were reading garbage and subsequently crashing.
>
>Reported-by: Karol Herbst <freedesktop@karolherbst.de>
>Reported-by: Tobias Klausmann <tobias.klausmann@mni.thm.de>
>Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91316
>Cc: Ilia Mirkin  <imirkin@alum.mit.edu>
>Cc: Martin Peres <martin.peres@linux.intel.com>
>Cc: Olivier Fourdan <ofourdan@redhat.com
>Cc: Adam Jackson <ajax@redhat.com>
>Cc: Alan Coopersmith <alan.coopersmith@oracle.com
>---
> os/WaitFor.c    |    2 +-
> os/connection.c |    4 ++--
> os/io.c         |    2 +-
> os/osdep.h      |    4 ++++
> 4 files changed, 8 insertions(+), 4 deletions(-)
>
>diff --git a/os/WaitFor.c b/os/WaitFor.c
>index 7137ee0..7b75615 100644
>--- a/os/WaitFor.c
>+++ b/os/WaitFor.c
>@@ -323,7 +323,7 @@ WaitForSomething(int *pClientsReady)
>     nready = 0;
>     if (XFD_ANYSET(&clientsReadable)) {
> #ifndef WIN32
>-        for (i = 0; i < howmany(XFD_SETSIZE, NFDBITS); i++) {
>+        for (i = 0; i < XFD_WORDS(&clientsReadable); i++) {
>             int highest_priority = 0;
> 
>             while (clientsReadable.fds_bits[i]) {
>diff --git a/os/connection.c b/os/connection.c
>index c36b125..ea3154d 100644
>--- a/os/connection.c
>+++ b/os/connection.c
>@@ -834,7 +834,7 @@ EstablishNewConnections(ClientPtr clientUnused, void *closure)
>         }
>     }
> #ifndef WIN32
>-    for (i = 0; i < howmany(XFD_SETSIZE, NFDBITS); i++) {
>+    for (i = 0; i < XFD_WORDS(&readyconnections); i++) {
>         while (readyconnections.fds_bits[i])
> #else
>     for (i = 0; i < XFD_SETCOUNT(&readyconnections); i++)
>@@ -1002,7 +1002,7 @@ CheckConnections(void)
>     notime.tv_usec = 0;
> 
> #ifndef WIN32
>-    for (i = 0; i < howmany(XFD_SETSIZE, NFDBITS); i++) {
>+    for (i = 0; i < XFD_WORDS(&AllClients); i++) {
>         mask = AllClients.fds_bits[i];
>         while (mask) {
>             curoff = mffs(mask) - 1;
>diff --git a/os/io.c b/os/io.c
>index c8e5058..334b519 100644
>--- a/os/io.c
>+++ b/os/io.c
>@@ -662,7 +662,7 @@ FlushAllOutput(void)
>     NewOutputPending = FALSE;
> 
> #ifndef WIN32
>-    for (base = 0; base < howmany(XFD_SETSIZE, NFDBITS); base++) {
>+    for (base = 0; base < XFD_WORDS(&OutputPending); base++) {
>         mask = OutputPending.fds_bits[base];
>         OutputPending.fds_bits[base] = 0;
>         while (mask) {
>diff --git a/os/osdep.h b/os/osdep.h
>index 77a5b53..15a2875 100644
>--- a/os/osdep.h
>+++ b/os/osdep.h
>@@ -98,6 +98,10 @@ SOFTWARE.
> /* MAXSELECT is the number of fds that select() can handle */
> #define MAXSELECT (sizeof(fd_set) * NBBY)
> 
>+#ifndef XFD_WORDS
>+#define XFD_WORDS(set) (sizeof(__FDS_BITS(set))/sizeof(__FDS_BITS(set)[0]))
>+#endif
>+
> #include <stddef.h>
> 
> #if defined(XDMCP) || defined(HASXDMAUTH)
>-- 
>1.7.10.4
>

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Attachments on bug 91316: 117074 | 117075 | 117194 | 117199 | 117200

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