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>
The BigRequest extension allows requests larger than the 16-bit length
limit.
It uses integers for the request length and checks for the size not to
exceed the maxBigRequestSize limit, but does so after translating the
length to integer by multiplying the given size in bytes by 4.
In doing so, it might overflow the integer size limit before actually
checking for the overflow, defeating the purpose of the test.
To avoid the issue, make sure to check that the request size does not
overflow the maxBigRequestSize limit prior to any conversion.
The caller Dispatch() function however expects the return value to be in
bytes, so we cannot just return the converted value in case of error, as
that would also overflow the integer size.
To preserve the existing API, we use a negative value for the X11 error
code BadLength as the function only return positive values, 0 or -1 and
update the caller Dispatch() function to take that case into account to
return the error code to the offending client.
CVE-2025-49176
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: Michel Dänzer <mdaenzer@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
We stopped including this in error messages back in 2008
Clears warning from clang 19.1.7:
os/utils.c:1338:9: warning: macro is not used [-Wunused-macros]
1338 | #define BUGADDRESS BUILDERADDR
| ^
Fixes: ef77e4c44 ("Remove useless commentary from environment and argument processing.")
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1910>
Several pieces of the code, as well as drivers are using %X, which
we don't support, so leading to error messages like this:
[2025-02-27 14:28:44] BUG: 'if (f[f_idx])'
[2025-02-27 14:28:44] BUG: ../xserver/os/log.c:538 in vpnprintf()
[2025-02-27 14:28:44] Unsupported printf directive 'X'
[2025-02-27 14:28:44]
[2025-02-27 14:28:44] Backtrace:
[2025-02-27 14:28:44] unw_get_proc_name failed: no unwind info found [-10]
[2025-02-27 14:28:44] 0: /usr/lib/Xorg (?+0x0) [0x5f4d1261bc47]
[2025-02-27 14:28:44] 1: /usr/lib/Xorg (LogVHdrMessageVerb+0x10f) [0x5f4d1261ca3f]
[2025-02-27 14:28:44] 2: /usr/lib/Xorg (LogHdrMessageVerb+0x85) [0x5f4d1261cae5]
[2025-02-27 14:28:44] 3: /usr/lib/Xorg (xf86VDrvMsgVerb+0x54) [0x5f4d12636604]
[2025-02-27 14:28:44] 4: /usr/lib/Xorg (xf86DrvMsg+0x97) [0x5f4d126367d7]
[2025-02-27 14:28:44] 5: /usr/lib/Xorg (xf86PrintEDID+0x545) [0x5f4d12654315]
[2025-02-27 14:28:44] 6: /usr/lib/Xorg (xf86OutputSetEDID+0x1bd) [0x5f4d12657e0d]
In the longer run, we'll have to decide whether we actually want to
implement the upper-case directive or change all callers to lower-case.
But for now it's better to just accept %X and interpret it as lower-case,
in order to fix those error messages. Whether it's printed as upper or
lower case is more or less an aesthetic matter.
Reported-By: guido iodice <guido.iodice@gmail.com>
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1846>
Not used by any external modules, so no need to keep it in public API.
Since it's used by DRI, still needs the _X_EXPORT flag, as long as DRI
is a dynamically loaded module.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1790>
Upstart is long dead, discontinued a decade ago, so there's no
need to keep around a special signaling logic just for it.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1791>
HAVE_BACKTRACE gets set on systems with libunwind however
execinfo.h may be missing (on *BSD or musl for example).
HAVE_EXECINFO_H has been defined by the build system for a long
time but previously not used.
Signed-off-by: Randy Palamar <randy@rnpnr.xyz>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1207>
This function doesn't much to do with logging, except for being
called once by FatalError(). It's better placed in utils.c
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1678>
```
../os/backtrace.c: In function ‘print_registers’:
../os/backtrace.c:94:52: error: passing argument 3 of ‘_ULarm_get_reg’ from incompatible pointer type [-Wincompatible-pointer-types]
94 | ret = unw_get_reg(&cursor, regs[i].regnum, &val);
| ^~~~
| |
| uint64_t * {aka long long unsigned int *}
```
Switched to libunwind's un_word_t type and PRIxPTR fprintf fmt specification
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1763>
Most of these flags aren't used by any drivers, so no need to keep them
exported. Only three exceptions: composite, Panoramix/Xinerama and Xv.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1519>
The OS abstraction isn't really the right place for those flags,
they are're probably better off in their corresponding extensions.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1519>
Since LogVMessageVerb() is now signal safe, we can use this one instead.
Leaving VErrorF() macro for backwards compat with drivers.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1691>
It really doesn't seem to be necessary to protect a LogVMessageVerb()
call by extra mutex on windows only, while obviously not needed on
any other platform.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1691>
Since VErrorF() is now signal safe, we can use this one instead.
Leaving VErrorFSigSafe() macro for backwards compat with drivers.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1691>
Since ErrorF() is now signal safe, we can use this one instead.
Leaving ErrorFSigSafe() macro for backwards compat with drivers.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1691>
Since LogMessageVerb() is now signal safe, we can use this one instead.
Leaving LogMessageVerbSigSafe() macro for backwards compat with drivers.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1691>
We already have our own signal safe vnsprintf() implementation, which is used
for formatting log messages while being in a signal handler, there's no need
to have two separate implementations of all the logging functions.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1691>
Simplify log formatting functions and remove redundancies, e.g.:
* common function for line termination
* copy prefix directly instead of *printf'ing it
* now just exactly one LogSWrite() call per message
(good for other log targets like syslog)
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1691>
PANORAMIX was the original working title of the extension, before it became
official standard. Just nobody cared about fixing the symbols to the official
naming.
For backwards compatibility with drivers, the old PANORAMIX symbol will
still be set.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1258>
Support for using inet_ntop() was originally added to support IPv6,
and only used for IPv6 addresses in AuthAudit(). Two decades later,
support for inet_ntop() is ubiquitous and OS'es have marked inet_ntoa()
as deprecated, so use the modern interface for IPv4 as well now.
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1760>
Support for using getaddrinfo() was originally added to support IPv6,
and only used if IPv6 support was enabled. Two decades later, support
for getaddrinfo() is ubiquitous and OS'es have marked gethostbyname()
as deprecated, so use the modern interface whenever we can now.
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1760>
If the compiler knows of a better algorithm for counting the number of
bits set in a word for the target CPU, let it use that, instead of the
classic algorithm optimized for PDP-6.
Based on xorg/lib/libxext@490a25e6f8a4d2482af4364c700b68ad11a4d10b
v2: make old version static inline, stop exporting after !1695
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1674>
The comment at the top of the function tells humans the fallthroughs
are intentional, but gcc doesn't parse that.
Clears 3 -Wimplicit-fallthrough warnings from gcc 14.1
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1716>
Olivier Fourdan
Alan Coopersmith
Enrico Weigelt, metux IT consult
Randy Palamar
Doug Johnson