[Linux-ia64] Shared memory

[Linux-ia64] Shared memory

[roneng]

Hi,
Has anyone had a problem using the shmctl function to change the access
mode of a shared memory
block?

What I am doing is allocating shared memory using mode 666, and writing to
it, then I use shmctl to change its
mode to 600, switch to another userid using su, and try and read from the
shared memory block. on ia32 linux
I get an permission denied error, on ia64 with the latest turbolinux kernel
and glibc i can read from that memory
block.


Thank you,
Ronen Grosman
- Phone: Internal:778-4478     External: (416)-448-4478    Fax:
(416)448-4414
- e-mail roneng@ca.ibm.com

Re: [Linux-ia64] Shared memory

[Christoph Rohland]

Hi Ronen,

roneng@ca.ibm.com writes:
> Has anyone had a problem using the shmctl function to change the access
> mode of a shared memory
> block?
> 
> What I am doing is allocating shared memory using mode 666, and writing to
> it, then I use shmctl to change its
> mode to 600, switch to another userid using su, and try and read from the
> shared memory block. on ia32 linux
> I get an permission denied error, on ia64 with the latest turbolinux kernel
> and glibc i can read from that memory
> block.

That's an arch independent bug in the shm code. I will try to make a
fix beginning next week.

Thanks for spotting this,
                		Christoph

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