6.12-stable review patch. If anyone has any objections, please let me know.
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From: Eric Sandeen sandeen@redhat.com
[ Upstream commit fda94a9919fd632033979ad7765a99ae3cab9289 ]
When generic_write_checks() returns zero, it means that iov_iter_count() is zero, and there is no work to do.
Simply return success like all other filesystems do, rather than proceeding down the write path, which today yields an -EFAULT in generic_perform_write() via the (fault_in_iov_iter_readable(i, bytes) == bytes) check when bytes == 0.
Fixes: 11a347fb6cef ("exfat: change to get file size from DataLength") Reported-by: Noah kernel-org-10@maxgrass.eu Signed-off-by: Eric Sandeen sandeen@redhat.com Reviewed-by: Yuezhang Mo Yuezhang.Mo@sony.com Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/exfat/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/exfat/file.c b/fs/exfat/file.c index 05b51e7217838..807349d8ea050 100644 --- a/fs/exfat/file.c +++ b/fs/exfat/file.c @@ -587,7 +587,7 @@ static ssize_t exfat_file_write_iter(struct kiocb *iocb, struct iov_iter *iter) valid_size = ei->valid_size;
ret = generic_write_checks(iocb, iter); - if (ret < 0) + if (ret <= 0) goto unlock;
if (iocb->ki_flags & IOCB_DIRECT) {