fsioctl.c: make generic_block_fiemap() signal-tolerant
__generic_block_fiemap may spin very long time for large sparse files.
Without this patch an unprivileged user may abuse system resources simply
by spawning a vast number of unkilable busyloops (works on ext2/ext3):
truncate --size 1T test
for ((i=0;i<1024;i++))
do
filefrag test > /dev/null &
done
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 files changed