diff options
| author | Dmitry Monakhov <dmonakhov@openvz.org> | 2015-02-10 22:09:29 (GMT) |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-10 22:30:30 (GMT) |
| commit | 913e027ca17ee06fa9436a21e54464795b0fa0e8 (patch) | |
| tree | d583200d611573204224ac54bb7f7f1a633950ef /Documentation/filesystems | |
| parent | 99b8874e79619498ade354357f64299768642af6 (diff) | |
| download | linux-913e027ca17ee06fa9436a21e54464795b0fa0e8.tar.xz | |
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>
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/fiemap.txt | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/Documentation/filesystems/fiemap.txt b/Documentation/filesystems/fiemap.txt index 1b805a0..f6d9c99 100644 --- a/Documentation/filesystems/fiemap.txt +++ b/Documentation/filesystems/fiemap.txt @@ -196,7 +196,8 @@ struct fiemap_extent_info { }; It is intended that the file system should not need to access any of this -structure directly. +structure directly. Filesystem handlers should be tolerant to signals and return +EINTR once fatal signal received. Flag checking should be done at the beginning of the ->fiemap callback via the |