Re: Oops on 2.4.x invalid procfs i_ino value

[William Lee Irwin III <wli@holomorphy.com>]

On Fri, Dec 17, 2004 at 04:49:44PM -0600, Brent Casavant wrote:
> Thus closing a proc entry for any task with a pid that is a multiple of
> 65536 will fail this check, skip proc_pid_delete_inode, and call
> __MOD_DEC_USE_COUNT, more than likely causing a panic on an invalid
> memory access, and minimally corrupting something in memory otherwise.
> I don't have a solution coded up (mostly because I'm a bit bleary
> eyed after looking at crash dumps all day) -- but are there any
> thoughts on how to go about addressing this one?  An obvious workaround
> is setting kernel.pid_max to 65535, but that's only a workaround, not
> a solution.
> On a related note, if it matters, on about half the crash dumps I've
> looked at, I see a pid of 0 has been assigned to a user process,
> tripping this same problem.  I suspect there's another bug somewhere
> that's allowing a pid of 0 to be chosen in the first place -- but I
> don't totally discount that this problem may lay in SGI's patches to
> this particular kernel -- I'll need to take a more thorough look.

That's rather ominous. I'll pore over pid.c and see what's going on.
Also, does the pid.c in your kernel version match 2.6.x-CURRENT?


-- wli