From: Jeff Garzik Date: Tue, 17 Oct 2006 07:10:39 +0000 (-0700) Subject: [PATCH] ISDN: fix drivers, by handling errors thrown by ->readstat() X-Git-Tag: v2.6.19-rc3~155 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=04518bfe8eac2e82b476fb2b0093527adc2bc791;p=pandora-kernel.git [PATCH] ISDN: fix drivers, by handling errors thrown by ->readstat() This is a particularly ugly on-failure bug, possibly security, since the lack of error handling here is covering up another class of bug: failure to handle copy_to_user() return values. The I4L API function ->readstat() returns an integer, and by looking at several existing driver implementations, it is clear that a negative return value was meant to indicate an error. Given that several drivers already return a negative value indicating an errno-style error, the current code would blindly accept that [negative] value as a valid amount of bytes read. Obvious damage ensues. Correcting ->readstat() handling to properly notice errors fixes the existing code to work correctly on error, and enables future patches to more easily indicate errors during operation. Signed-off-by: Jeff Garzik Cc: Karsten Keil Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed