From: Mathias Krause Date: Sat, 4 Oct 2014 21:06:39 +0000 (+0200) Subject: posix-timers: Fix stack info leak in timer_create() X-Git-Tag: omap-for-v3.19/fixes-not-urgent-part1~33^2~2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6891c4509c792209c44ced55a60f13954cb50ef4;p=pandora-kernel.git posix-timers: Fix stack info leak in timer_create() If userland creates a timer without specifying a sigevent info, we'll create one ourself, using a stack local variable. Particularly will we use the timer ID as sival_int. But as sigev_value is a union containing a pointer and an int, that assignment will only partially initialize sigev_value on systems where the size of a pointer is bigger than the size of an int. On such systems we'll copy the uninitialized stack bytes from the timer_create() call to userland when the timer actually fires and we're going to deliver the signal. Initialize sigev_value with 0 to plug the stack info leak. Found in the PaX patch, written by the PaX Team. Fixes: 5a9fa7307285 ("posix-timers: kill ->it_sigev_signo and...") Signed-off-by: Mathias Krause Cc: Oleg Nesterov Cc: Brad Spengler Cc: PaX Team Cc: # v2.6.28+ Link: http://lkml.kernel.org/r/1412456799-32339-1-git-send-email-minipli@googlemail.com Signed-off-by: Thomas Gleixner --- Reading git-diff-tree failed