commit 2c724fb92732c0b2a5629eb8af74e82eb62ac947
author Anton Blanchard <anton@samba.org> Fri Mar 16 10:28:07 2012 +0000
committer Linus Torvalds <torvalds@linux-foundation.org> Fri Mar 16 17:01:41 2012 -0700
tree 3364c51ab27f410823e1ed4e7c3e4515d6b8b93c
parent 0c4d0670f6e54f8507c30c01928cc9ff630ca497

afs: Read of file returns EBADMSG

A read of a large file on an afs mount failed:

# cat junk.file > /dev/null
cat: junk.file: Bad message

Looking at the trace, call->offset wrapped since it is only an
unsigned short. In afs_extract_data:

        _enter("{%u},{%zu},%d,,%zu", call->offset, len, last, count);
...

        if (call->offset < count) {
                if (last) {
                        _leave(" = -EBADMSG [%d < %zu]", call->offset, count);
                        return -EBADMSG;
                }

Which matches the trace:

[cat   ] ==> afs_extract_data({65132},{524},1,,65536)
[cat   ] <== afs_extract_data() = -EBADMSG [0 < 65536]

call->offset went from 65132 to 0. Fix this by making call->offset an
unsigned int.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>