From 0439e091e3b1fe41a350540c84857a573fde3d72 Mon Sep 17 00:00:00 2001 From: Jie Liu Date: Thu, 2 Jan 2014 11:30:42 -0600 Subject: [PATCH] jfs: fix xattr value size overflow in __jfs_setxattr There is a potential overflow if the specified EA value size is greater than USHRT_MAX because the size of value is limited by the on-disk format (i.e, __le16), this issue could be reflected via the tests below: # touch /jfs/testfile # setfattr -n user.comment -v `perl -e 'print "A"x65536'` /jfs/testfile setfattr: /jfs/testfile: Invalid argument Syslog: ... jfs_xsetattr: xattr_size = 21, new_size = 65557 This patch add pre-checkups of EA value size against USHRT_MAX to avoid this problem, and return -E2BIG which is consistent with the VFS setxattr interface. Moreover, fix the debug code to print the correct function name. With this fix: setfattr: /jfs/testfile: Argument list too long Signed-off-by: Jie Liu Signed-off-by: Dave Kleikamp --- fs/jfs/xattr.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c index d3472f4..9c6904e 100644 --- a/fs/jfs/xattr.c +++ b/fs/jfs/xattr.c @@ -860,6 +860,19 @@ int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name, /* Completely new ea list */ xattr_size = sizeof (struct jfs_ea_list); + /* + * The size of EA value is limitted by on-disk format up to + * __le16, there would be an overflow if the size is equal + * to XATTR_SIZE_MAX (65536). In order to avoid this issue, + * we can pre-checkup the value size against USHRT_MAX, and + * return -E2BIG in this case, which is consistent with the + * VFS setxattr interface. + */ + if (value_len >= USHRT_MAX) { + rc = -E2BIG; + goto release; + } + ea = (struct jfs_ea *) ((char *) ealist + xattr_size); ea->flag = 0; ea->namelen = namelen; @@ -874,7 +887,7 @@ int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name, /* DEBUG - If we did this right, these number match */ if (xattr_size != new_size) { printk(KERN_ERR - "jfs_xsetattr: xattr_size = %d, new_size = %d\n", + "__jfs_setxattr: xattr_size = %d, new_size = %d\n", xattr_size, new_size); rc = -EINVAL; -- 2.7.4