From: Ivan Vecera ivecera@redhat.com
This patch has been added to the 4.1 stable tree. If you have any objections, please let us know.
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[ Upstream commit ba87977a49913129962af8ac35b0e13e0fa4382d ]
Commit b7ce40cff0b9 ("kernfs: cache atomic_write_len in kernfs_open_file") changes type of local variable 'len' from ssize_t to size_t. This change caused that the *ppos value is updated also when the previous write callback failed.
Mentioned snippet: ... len = ops->write(...); <- return value can be negative ... if (len > 0) <- true here in this case *ppos += len; ...
Fixes: b7ce40cff0b9 ("kernfs: cache atomic_write_len in kernfs_open_file") Acked-by: Tejun Heo tj@kernel.org Signed-off-by: Ivan Vecera ivecera@redhat.com Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- fs/kernfs/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c index 9ff28bc294c0..5d084638e1f8 100644 --- a/fs/kernfs/file.c +++ b/fs/kernfs/file.c @@ -272,7 +272,7 @@ static ssize_t kernfs_fop_write(struct file *file, const char __user *user_buf, { struct kernfs_open_file *of = kernfs_of(file); const struct kernfs_ops *ops; - size_t len; + ssize_t len; char *buf;
if (of->atomic_write_len) {