diff options
author | NeilBrown <neilb@suse.de> | 2006-09-16 19:15:37 (GMT) |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-16 19:54:30 (GMT) |
commit | ecaff756ff540f3821e2b00b8fa19aca07c7c3e5 (patch) | |
tree | 80c40b24ad9228dcd7cf48c798250a9ccc74887a | |
parent | 55ebcc38a5f6d40e4c41447e413ef842b803980f (diff) | |
download | linux-fsl-qoriq-ecaff756ff540f3821e2b00b8fa19aca07c7c3e5.tar.xz |
[PATCH] knfsd: Have ext2 reject file handles with bad inode numbers early
This prevents bad inode numbers from triggering errors in ext2_get_inode.
[akpm@osdl.org: speedup, cleanup]
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r-- | fs/ext2/super.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 681dea8..ca5bfb6 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -251,6 +251,44 @@ static struct super_operations ext2_sops = { #endif }; +static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp) +{ + __u32 *objp = vobjp; + unsigned long ino = objp[0]; + __u32 generation = objp[1]; + struct inode *inode; + struct dentry *result; + + if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) + return ERR_PTR(-ESTALE); + if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) + return ERR_PTR(-ESTALE); + + /* iget isn't really right if the inode is currently unallocated!! + * ext2_read_inode currently does appropriate checks, but + * it might be "neater" to call ext2_get_inode first and check + * if the inode is valid..... + */ + inode = iget(sb, ino); + if (inode == NULL) + return ERR_PTR(-ENOMEM); + if (is_bad_inode(inode) || + (generation && inode->i_generation != generation)) { + /* we didn't find the right inode.. */ + iput(inode); + return ERR_PTR(-ESTALE); + } + /* now to find a dentry. + * If possible, get a well-connected one + */ + result = d_alloc_anon(inode); + if (!result) { + iput(inode); + return ERR_PTR(-ENOMEM); + } + return result; +} + /* Yes, most of these are left as NULL!! * A NULL value implies the default, which works with ext2-like file * systems, but can be improved upon. @@ -258,6 +296,7 @@ static struct super_operations ext2_sops = { */ static struct export_operations ext2_export_ops = { .get_parent = ext2_get_parent, + .get_dentry = ext2_get_dentry, }; static unsigned long get_sb_block(void **data) |