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[PATCH] kmsg_write: don't return printk return value

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kmsg_write returns with printk, so some programs may be confused by a
successful write() with a return value different than the buffer length.

# /bin/echo something > /dev/kmsg
/bin/echo: write error: Inappropriate ioctl for device

The drawbacks is that the printk return value can no more be quickly
checked from userspace.

Signed-off-by: Guillaume Chazarain <guichaz@yahoo.fr>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Guillaume Chazarain
2006-01-08 01:02:43 -08:00
committed by Linus Torvalds
parent 025510cd20
commit cd140a5c1f
1 changed files with 4 additions and 1 deletions
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5
drivers/char/mem.c
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@@ -817,7 +817,7 @@ static ssize_t kmsg_write(struct file * file, const char __user * buf,
size_t count, loff_t *ppos) size_t count, loff_t *ppos)
{ {
char *tmp; char *tmp;
int ret; ssize_t ret;
tmp = kmalloc(count + 1, GFP_KERNEL); tmp = kmalloc(count + 1, GFP_KERNEL);
if (tmp == NULL) if (tmp == NULL)
@@ -826,6 +826,9 @@ static ssize_t kmsg_write(struct file * file, const char __user * buf,
if (!copy_from_user(tmp, buf, count)) { if (!copy_from_user(tmp, buf, count)) {
tmp[count] = 0; tmp[count] = 0;
ret = printk("%s", tmp); ret = printk("%s", tmp);
if (ret > count)
/* printk can add a prefix */
ret = count;
} }
kfree(tmp); kfree(tmp);
return ret; return ret;