Commit db77ec27 authored by Alan Curry's avatar Alan Curry Committed by Linus Torvalds
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[PATCH] framebuffer: cmap-setting return values

A set of 3 small bugfixes, all of which are related to bogus return values
of fb colormap-setting functions.

First, fb_alloc_cmap returns -1 if memory allocation fails. This is a hard
condition to reproduce since you'd have to be really low on memory, but from
studying the contexts in which it is called, I think this function should be
returning a negative errno, and the -1 will be seen as an EPERM. Switching it
to -ENOMEM makes sense.

Second, the store_cmap function which is called for writes to
/sys/class/graphics/fb0/color_map returns 0 for success, but it should be
returning the count of bytes written since its return value ends up in
userspace as the result of the write() syscall.

Third, radeonfb returns 1 instead of a negative errno when FBIOPUTCMAP is
called with an oversized colormap.  This is seen in userspace as a return
value of 1 from the ioctl() syscall with errno left unchanged.  A more
useful return value would be -EINVAL.

Signed-off-by: default avatarAlan Curry <>
Cc: "Antonino A. Daplas" <>
Cc: Benjamin Herrenschmidt <>
Signed-off-by: default avatarAndrew Morton <>
Signed-off-by: default avatarLinus Torvalds <>
parent 59153f7d
......@@ -1067,7 +1067,7 @@ static int radeon_setcolreg (unsigned regno, unsigned red, unsigned green,
if (regno > 255)
return 1;
return -EINVAL;
red >>= 8;
green >>= 8;
......@@ -1086,9 +1086,9 @@ static int radeon_setcolreg (unsigned regno, unsigned red, unsigned green,
pindex = regno * 8;
if (rinfo->depth == 16 && regno > 63)
return 1;
return -EINVAL;
if (rinfo->depth == 15 && regno > 31)
return 1;
return -EINVAL;
/* For 565, the green component is mixed one order
* below
......@@ -85,7 +85,7 @@ static struct fb_cmap default_16_colors = {
* Allocates memory for a colormap @cmap. @len is the
* number of entries in the palette.
* Returns -1 errno on error, or zero on success.
* Returns negative errno on error, or zero on success.
......@@ -116,7 +116,7 @@ int fb_alloc_cmap(struct fb_cmap *cmap, int len, int transp)
return -1;
return -ENOMEM;
......@@ -348,7 +348,7 @@ static ssize_t store_cmap(struct class_device *class_device, const char *buf,
fb_copy_cmap(&umap, &fb_info->cmap);
return rc;
return rc ?: count;
for (i = 0; i < length; i++) {
u16 red, blue, green, tsp;
......@@ -367,7 +367,7 @@ static ssize_t store_cmap(struct class_device *class_device, const char *buf,
if (transp)
fb_info->cmap.transp[i] = tsp;
return 0;
return count;
static ssize_t show_cmap(struct class_device *class_device, char *buf)
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