andreacavalli/xserver-multidpi
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dmx: Fix some snprintf warnings.

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snprintf doesn't terminate the string if it truncates, so things like
this are lurking crashers:

../hw/dmx/dmxprop.c: In function ‘dmxPropertyIdentifier.part.0’:
../hw/dmx/dmxprop.c:94:36: warning: ‘%s’ directive output may be truncated writing up to 255 bytes into a region of size 123 [-Wformat-truncation=]
     snprintf(buf, sizeof(buf), "%s:%s:%s", DMX_IDENT, hostname, display);
                                    ^~                 ~~~~~~~~
../hw/dmx/dmxprop.c:94:5: note: ‘snprintf’ output 7 or more bytes (assuming 262) into a destination of size 128
     snprintf(buf, sizeof(buf), "%s:%s:%s", DMX_IDENT, hostname, display);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../hw/dmx/dmxprop.c: In function ‘dmxPropertyWindow’:
../hw/dmx/dmxprop.c:372:36: warning: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size between 0 and 127 [-Wformat-truncation=]
     snprintf(buf, sizeof(buf), "%s,%d", id, dmxScreen->index);
                                    ^~
../hw/dmx/dmxprop.c:372:5: note: ‘snprintf’ output between 3 and 140 bytes into a destination of size 128
     snprintf(buf, sizeof(buf), "%s,%d", id, dmxScreen->index);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We could be more precise about termination, but meh.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Acked-by: Keith Packard <keithp@keithp.com>
This commit is contained in:
Adam Jackson 2018-04-05 12:31:04 -04:00
parent 4c1453393f
commit c3b190f9da
1 changed files with 2 additions and 2 deletions
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4
hw/dmx/dmxprop.c
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@ -84,7 +84,7 @@ dmxPropertyIdentifier(void)
/* RATS: These buffers are only used in
* length-limited calls. */
char hostname[256];
static char buf[128];
static char buf[512];
static int initialized = 0;
if (initialized++)
@ -346,7 +346,7 @@ dmxPropertyWindow(DMXScreenInfo * dmxScreen)
Display *dpy = dmxScreen->beDisplay;
Window win = dmxScreen->scrnWin;
DMXScreenInfo *other;
char buf[128]; /* RATS: only used with snprintf */
char buf[1024]; /* RATS: only used with snprintf */
if (!dpy)
return; /* FIXME: What should be done here if Xdmx is started