From: Theodore Ts'o <tytso@xxxxxxx> Date: Fri, 16 Jun 2017 08:50:07 -0400 > On Thu, Jun 15, 2017 at 11:01:18AM -0400, David Miller wrote: >> As a side note, ext4 does something similar with a private >> implementation, but it doesn't use something the evaluates to an >> alloca. Instead it uses a fixed 4-byte size for the shash context >> value in the on-stack declaration. > > In ext4's case, we're doing it inside an inline function, and then > using the "return" value from inside the calling function. Assuming > that gcc actually inlines the function, are we in danger of tripping > over the bug? Again, the bug can only be triggered if you do a dynamically sized object on the stack. Which ext4 is not doing, since it uses fixed size elements in the on-stack shash context.
