xserver/os
Olivier Fourdan 5279ee435c os: Account for bytes to ignore when sharing input buffer
When reading requests from the clients, the input buffer might be shared
and used between different clients.

If a given client sends a full request with non-zero bytes to ignore,
the bytes to ignore may still be non-zero even though the request is
full, in which case the buffer could be shared with another client who's
request will not be processed because of those bytes to ignore, leading
to a possible hang of the other client request.

To avoid the issue, make sure we have zero bytes to ignore left in the
input request when sharing the input buffer with another client.

CVE-2025-49178

This issue was discovered by Nils Emmerich <nemmerich@ernw.de> and
reported by Julian Suleder via ERNW Vulnerability Disclosure.

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
(cherry picked from commit d55c54cecb)
2026-01-25 10:40:01 -08:00
..
.gitignore dix and os: gitignore dix.O and os.O 2011-09-23 17:14:47 -07:00
access.c os: if getaddrinfo() is available, use it, even if IPv6 support is disabled 2026-01-25 10:39:58 -08:00
auth.c os: drop SUN-DES-1 authentication 2026-01-25 10:39:53 -08:00
backtrace.c os: backtrace: Fix -Wincompatible-pointer-types compiler error on 32-bit targets 2026-01-25 10:40:00 -08:00
busfault.c include: move busfault.h out of public include dir 2026-01-19 12:32:26 -08:00
busfault.h os: fix missing include of misc.h in busfault.h 2026-01-19 12:48:30 -08:00
client.c Return NULL in *cmdname if the client argv or argv[0] is NULL 2026-01-25 10:39:56 -08:00
connection.c os: drop upstart specific SIGSTOP signaling logic 2026-01-25 10:40:00 -08:00
inputthread.c os, shm: fcntl()'s third argument is integer, not pointer 2020-12-18 09:36:30 -05:00
io.c os: Account for bytes to ignore when sharing input buffer 2026-01-25 10:40:01 -08:00
log.c os: let vpnprintf() accept %X 2026-01-25 10:40:01 -08:00
meson.build os: drop SUN-DES-1 authentication 2026-01-25 10:39:53 -08:00
mitauth.c os: Use memcpy() instead of memmove() when buffers are known not to overlap 2022-08-29 21:10:51 +00:00
oscolor.c os: unexport OsLookupColor() 2026-01-19 12:47:57 -08:00
osdep.h dix: Use __builtin_popcountl if available to replace Ones() 2026-01-25 10:39:57 -08:00
osinit.c os/osinit: fix build when execinfo.h is missing 2026-01-25 10:40:00 -08:00
ospoll.c os: move xserver_poll.h into os/ directory 2026-01-25 10:39:54 -08:00
ospoll.h os: Add ospoll interface [v2] 2016-07-21 15:04:47 -04:00
reallocarray.c Import reallocarray() from OpenBSD 2015-04-21 16:57:08 -07:00
strcasecmp.c Introduce a consistent coding style 2012-03-21 13:54:42 -07:00
strcasestr.c os: fix mising prototype / include on WIN32 builds 2026-01-19 12:32:19 -08:00
strlcat.c Introduce a consistent coding style 2012-03-21 13:54:42 -07:00
strlcpy.c Introduce a consistent coding style 2012-03-21 13:54:42 -07:00
strndup.c os: Ensure <dix-config.h> is included in strndup.c 2013-02-14 09:20:46 -08:00
timingsafe_memcmp.c timingsafe_memcmp: Fix meson build 2017-05-10 10:56:16 -04:00
utils.c os: remove unused definition of BUGADDRESS 2026-01-25 10:40:01 -08:00
WaitFor.c os: NextDPMSTimeout: mark intentional fallthroughs in switch 2026-01-25 10:39:57 -08:00
xdmauth.c os: Use memcpy() instead of memmove() when buffers are known not to overlap 2022-08-29 21:10:51 +00:00
xdmcp.c os: if getaddrinfo() is available, use it, even if IPv6 support is disabled 2026-01-25 10:39:58 -08:00
xprintf.c Remove "All rights reserved" from Oracle copyright notices 2023-02-25 09:40:41 -08:00
xserver_poll.c os: move xserver_poll.h into os/ directory 2026-01-25 10:39:54 -08:00
xserver_poll.h os: move xserver_poll.h into os/ directory 2026-01-25 10:39:54 -08:00
xsha1.c include: move xsha1.h to os/ 2026-01-19 12:32:20 -08:00
xsha1.h include: move xsha1.h to os/ 2026-01-19 12:32:20 -08:00
xstrans.c Clean up a couple of warnings in os/ 2013-10-31 16:58:12 -07:00