diff options
| author | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2015-05-05 16:24:00 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-05-17 09:53:49 -0700 |
| commit | 63c3723947435afa0cb01bd3413189ba2a20d4c3 (patch) | |
| tree | cb02b502e00041d9adc80446dd4756c34d3412b8 | |
| parent | c87e1582d7d4b37767c79a5a352340aea886c748 (diff) | |
nilfs2: fix sanity check of btree level in nilfs_btree_root_broken()
commit d8fd150fe3935e1692bf57c66691e17409ebb9c1 upstream.
The range check for b-tree level parameter in nilfs_btree_root_broken()
is wrong; it accepts the case of "level == NILFS_BTREE_LEVEL_MAX" even
though the level is limited to values in the range of 0 to
(NILFS_BTREE_LEVEL_MAX - 1).
Since the level parameter is read from storage device and used to index
nilfs_btree_path array whose element count is NILFS_BTREE_LEVEL_MAX, it
can cause memory overrun during btree operations if the boundary value
is set to the level parameter on device.
This fixes the broken sanity check and adds a comment to clarify that
the upper bound NILFS_BTREE_LEVEL_MAX is exclusive.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/nilfs2/btree.c | 2 | ||||
| -rw-r--r-- | include/linux/nilfs2_fs.h | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/fs/nilfs2/btree.c b/fs/nilfs2/btree.c index ecdbae19a766..090d8ce25bd1 100644 --- a/fs/nilfs2/btree.c +++ b/fs/nilfs2/btree.c @@ -388,7 +388,7 @@ static int nilfs_btree_root_broken(const struct nilfs_btree_node *node, nchildren = nilfs_btree_node_get_nchildren(node); if (unlikely(level < NILFS_BTREE_LEVEL_NODE_MIN || - level > NILFS_BTREE_LEVEL_MAX || + level >= NILFS_BTREE_LEVEL_MAX || nchildren < 0 || nchildren > NILFS_BTREE_ROOT_NCHILDREN_MAX)) { pr_crit("NILFS: bad btree root (inode number=%lu): level = %d, flags = 0x%x, nchildren = %d\n", diff --git a/include/linux/nilfs2_fs.h b/include/linux/nilfs2_fs.h index 98755767c7b0..1108acaacfc6 100644 --- a/include/linux/nilfs2_fs.h +++ b/include/linux/nilfs2_fs.h @@ -458,7 +458,7 @@ struct nilfs_btree_node { /* level */ #define NILFS_BTREE_LEVEL_DATA 0 #define NILFS_BTREE_LEVEL_NODE_MIN (NILFS_BTREE_LEVEL_DATA + 1) -#define NILFS_BTREE_LEVEL_MAX 14 +#define NILFS_BTREE_LEVEL_MAX 14 /* Max level (exclusive) */ /** * struct nilfs_palloc_group_desc - block group descriptor |