mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
afs: Fix total-length calculation for multiple-page send
Fix the total-length calculation in afs_make_call() when the operation being dispatched has data from a series of pages attached. Despite the patched code looking like that it should reduce mathematically to the current code, it doesn't because the 32-bit unsigned arithmetic being used to calculate the page-offset-difference doesn't correctly extend to a 64-bit value when the result is effectively negative. Without this, some FS.StoreData operations that span multiple pages fail, reporting too little or too much data. Signed-off-by: David Howells <dhowells@redhat.com>
This commit is contained in:
parent
5f0fc8ba6a
commit
1199db6035
1 changed files with 11 additions and 2 deletions
|
@ -350,8 +350,17 @@ long afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call,
|
|||
*/
|
||||
tx_total_len = call->request_size;
|
||||
if (call->send_pages) {
|
||||
tx_total_len += call->last_to - call->first_offset;
|
||||
tx_total_len += (call->last - call->first) * PAGE_SIZE;
|
||||
if (call->last == call->first) {
|
||||
tx_total_len += call->last_to - call->first_offset;
|
||||
} else {
|
||||
/* It looks mathematically like you should be able to
|
||||
* combine the following lines with the ones above, but
|
||||
* unsigned arithmetic is fun when it wraps...
|
||||
*/
|
||||
tx_total_len += PAGE_SIZE - call->first_offset;
|
||||
tx_total_len += call->last_to;
|
||||
tx_total_len += (call->last - call->first - 1) * PAGE_SIZE;
|
||||
}
|
||||
}
|
||||
|
||||
/* create a call */
|
||||
|
|
Loading…
Reference in a new issue