On Wed, Sep 28, 2016 at 11:42:11AM +1000, Michael Ellerman wrote: > But this is not really a powerpc patch, and I'm not an ELF expert. So > I'm not comfortable merging it via the powerpc tree. It doesn't look > like we really have a maintainer for binfmt_elf.c, so I'm not sure who > should be acking that part. Thanks a bunch for looking at this Michael. > I've added Al Viro to Cc, he maintains fs/ and might be interested. > I've also added Andrew Morton who might be happy to put this in his > tree, and see if anyone complains? For those added to the CC, I would re-state my original commit message more clearly. My research showed that the ELF loader bug fixed in this patch is the root cause bug fix required to implement this hunk: > > -#define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \ > > +#define VM_DATA_DEFAULT_FLAGS32 \ > > + (((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) | \ > > + VM_READ | VM_WRITE | \ > > VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) Eg that 32 bit powerpc currently unconditionally injects writable, executable pages into a user space process. This critically undermines all the W^X security work that has been done in the tool chain and user space by the PPC community. I would encourage people to view this as an important security patch for 32 bit powerpc environments. Regards, Jason -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>