> This was always racy, but 268720903f87e0b84b161626c4447b81671b5d18 > "uprobes: Rework register_for_each_vma() to make it O(n)" should be > blamed anyway, it made everything worse and I didn't notice. > > register/unregister call build_map_info() and then do install/remove > breakpoint for every mm which mmaps inode/offset. This can obviously > race with fork()->dup_mmap() in between and we can miss the child. > > uprobe_register() could be easily fixed but unregister is much worse, > the new mm inherits "int3" from parent and there is no way to detect > this if uprobe goes away. > > So this patch simply adds brw_start/end_read() around dup_mmap(), and > brw_start/end_write() into register_for_each_vma(). > > This adds 2 new hooks into dup_mmap() but we can kill uprobe_dup_mmap() > and fold it into uprobe_end_dup_mmap(). > > Reported-by: Srikar Dronamraju <[email protected]> > Signed-off-by: Oleg Nesterov <[email protected]>
Acked-by: Srikar Dronamraju <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
