Oleg Nesterov 4710f05fd1 uprobes: Fix prepare_uprobe() race with itself ... install_breakpoint() is called under mm->mmap_sem, this protects set_swbp() but not prepare_uprobe(). Two or more different tasks can call install_breakpoint()->prepare_uprobe() at the same time, this leads to numerous problems if UPROBE_COPY_INSN is not set. Just for example, the second copy_insn() can corrupt the already analyzed/fixuped uprobe->arch.insn and race with handle_swbp(). This patch simply adds uprobe->copy_mutex to serialize this code. We could probably reuse ->consumer_rwsem, but this would mean that consumer->handler() can not use mm->mmap_sem, not good. Note: this is another temporary ugly hack until we move this logic into uprobe_register(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>		2012-10-07 21:19:43 +02:00
..
callchain.c	perf: Add attribute to filter out callchains	2012-08-10 12:40:57 -03:00
core.c	perf: Add ability to attach user stack dump to sample	2012-08-10 12:17:58 -03:00
hw_breakpoint.c	Merge branch 'x86/cleanups' into perf/uprobes	2012-03-13 16:33:03 +01:00
internal.h	perf: Add ability to attach user stack dump to sample	2012-08-10 12:17:58 -03:00
Makefile	uprobes: Move to kernel/events/	2012-02-22 11:08:00 +01:00
ring_buffer.c	perf: Add perf_output_skip function to skip bytes in sample	2012-08-10 12:16:22 -03:00
uprobes.c	uprobes: Fix prepare_uprobe() race with itself	2012-10-07 21:19:43 +02:00