Hi Dave, > > > > Commit: 2b2e64be763c5e64d4ae4a061825b18decf1edf7 > > > > Author: Marcel Holtmann <[EMAIL PROTECTED]> Mon, 08 Jan 2007 01:00:33 > > > > +0100 > > > > > > > > [Bluetooth] Fix uninitialized return value for RFCOMM sendmsg() > > > > > > > > When calling send() with a zero length parameter on a RFCOMM socket > > > > it returns a positive value. In this rare case the variable err is > > > > used uninitialized and unfortunately its value is returned. > > > > > > > > Signed-off-by: Marcel Holtmann <[EMAIL PROTECTED]> > > > > > > You can't fix this bug like that. > > > > > > If sendmsg() sends any bytes, it should return the number of > > > bytes sent even if an error occurs mid-stream. > > > > > > With this change, you'll now return the error instead of > > > the number of bytes sent. That's what the new "sent = err" > > > assignment does. > > > > > > You have to do sendmsg() with those semantics, or else you lose > > > information in that the user can never know how many bytes were > > > actually sent successfully. Losing the error after successfully sent > > > bytes is OK, if the error persists the user will get it when it > > > recalls sendmsg() to push the rest of the remaining bytes out. > > > > > > The original code tried to do it right. > > > > > > If the bug is that 'err' is uninitialized, why try to fix this > > > by being fancy, just initialize it :-) > > > > We have "int sent = 0" and exactly that is returned if "len == 0". > > Marcel, please reread my email, then you can hit reply again ok :) > > You broke the case where len != 0, you're going to return an error > code when "sent != 0" and that's a bug, sendmsg() must return the > number of bytes sent if non-zero even if an error occurs.
it is way too late and you are absolutely right. However since the current code doesn't produce a compiler warning of an uninitialized variable, I prefer to not go with a "int err = 0" to make this work. I rebuild the tree with the correct fix in it and it is now ready to be pulled. Regards Marcel - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
