| Message ID | 1413922170-27434-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/fs/super.c b/fs/super.c index e5f6c2c..97edaa93 100644 --- a/fs/super.c +++ b/fs/super.c @@ -81,6 +81,8 @@ static unsigned long super_cache_scan(struct shrinker *shrink, inodes = list_lru_count_node(&sb->s_inode_lru, sc->nid); dentries = list_lru_count_node(&sb->s_dentry_lru, sc->nid); total_objects = dentries + inodes + fs_objects + 1; + if (!total_objects) + total_objects = 1; /* proportion the scan between the caches */ dentries = mult_frac(sc->nr_to_scan, dentries, total_objects);
This is a note to let you know that I have just added a patch titled fs: Fix theoretical division by 0 in super_cache_scan(). to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.10. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From b92a2fc33619cf3aadd46ed4ac66e3b53b4f2cc2 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Date: Sat, 17 May 2014 20:56:38 +0900 Subject: fs: Fix theoretical division by 0 in super_cache_scan(). commit 475d0db742e3755c6b267f48577ff7cbb7dfda0d upstream. total_objects could be 0 and is used as a denom. While total_objects is a "long", total_objects == 0 unlikely happens for 3.12 and later kernels because 32-bit architectures would not be able to hold (1 << 32) objects. However, total_objects == 0 may happen for kernels between 3.1 and 3.11 because total_objects in prune_super() was an "int" and (e.g.) x86_64 architecture might be able to hold (1 << 32) objects. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- fs/super.c | 2 ++ 1 file changed, 2 insertions(+) -- 1.9.1