diff options
authorPaul Mundt <lethal@linux-sh.org>2007-03-05 00:30:31 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-03-05 07:57:51 -0800
commit1f2b69f9bdce8461341e5fb864568a2ee90079c8 (patch)
parent[PATCH] sched: remove SMT nice (diff)
[PATCH] fb: sm501fb off-by-1 sysfs store
Currently sm501fb_crtsrc_store() won't allow the routing to be changed via echos from userspace in to the sysfs file. The reason for this is that the strnicmp() for both heads uses a sizeof() for the string length, which ends up being strlen() + 1 (\0 in the normal case, but the echo gives a newline, which is where the issue occurs), this then causes a mismatch and subsequently bails with the -EINVAL. In addition to this, the hardcoded lengths were then used for the store length that was returned, which ended up being erroneous and resulting in a write error. There's also no point in returning anything but the full length since it will -EINVAL out on a mismatch well before then anyways. sizeof("string") is great for making sure you have space in your buffer, but rather less so for string comparisons :-) Signed-off-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Ben Dooks <ben-linux@fluff.org> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/video/sm501fb.c b/drivers/video/sm501fb.c
index 58c0ac733db9..0a44c44672c8 100644
--- a/drivers/video/sm501fb.c
+++ b/drivers/video/sm501fb.c
@@ -1074,9 +1074,9 @@ static ssize_t sm501fb_crtsrc_store(struct device *dev,
if (len < 1)
return -EINVAL;
- if (strnicmp(buf, "crt", sizeof("crt")) == 0)
+ if (strnicmp(buf, "crt", 3) == 0)
head = HEAD_CRT;
- else if (strnicmp(buf, "panel", sizeof("panel")) == 0)
+ else if (strnicmp(buf, "panel", 5) == 0)
head = HEAD_PANEL;
return -EINVAL;
@@ -1098,7 +1098,7 @@ static ssize_t sm501fb_crtsrc_store(struct device *dev,
writel(ctrl, info->regs + SM501_DC_CRT_CONTROL);
- return (head == HEAD_CRT) ? 3 : 5;
+ return len;
/* Prepare the device_attr for registration with sysfs later */