tree 9e3fd1c9e61e8ed16959d115a9a3f6f7eb0bbf21
parent ffb45122766db220d0bf3d01848d575fbbcb6430
author Alexey Dobriyan <adobriyan@sw.ru> 1178609323 -0700
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1178648108 -0700

Fix race between cat /proc/*/wchan and rmmod et al

kallsyms_lookup() can go iterating over modules list unprotected which is OK
for emergency situations (oops), but not OK for regular stuff like
/proc/*/wchan.

Introduce lookup_symbol_name()/lookup_module_symbol_name() which copy symbol
name into caller-supplied buffer or return -ERANGE.  All copying is done with
module_mutex held, so...

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>