The patch titled
Subject: VFS: seq_file: ensure ->from is valid
has been removed from the -mm tree. Its filename was
vfs-simplify-seq_file-iteration-code-and-interface-fix.patch
This patch was dropped because it was folded into vfs-simplify-seq_file-iteration-code-and-interface.patch
------------------------------------------------------
From: NeilBrown <neilb@xxxxxxxx>
Subject: VFS: seq_file: ensure ->from is valid
Previous patch ("VFS: simplify seq_file iteration code and interface")
removed code to set ->from to zero when ->count is zero, as ->from is
dead at that time. However it didn't ensure ->from was set properly
whenever ->count becomes non-zero.
This can only happen when ->show() is called. Of the three places it
is called one already has ->from set to zero. The other two are
fixed by setting from to zero after fully flushing the buffer (at which
point ->count will also be zero).
Link: http://lkml.kernel.org/r/87601ryb8a.fsf@xxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: NeilBrown <neilb@xxxxxxxx>
Reported-by: Jann Horn <jannh@xxxxxxxxxx>
Tested-by: Jann Horn <jannh@xxxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/seq_file.c | 1 +
1 file changed, 1 insertion(+)
--- a/fs/seq_file.c~vfs-simplify-seq_file-iteration-code-and-interface-fix
+++ a/fs/seq_file.c
@@ -220,6 +220,7 @@ ssize_t seq_read(struct file *file, char
goto Done;
}
/* we need at least one record in buffer */
+ m->from = 0;
p = m->op->start(m, &m->index);
while (1) {
err = PTR_ERR(p);
_
Patches currently in -mm which might be from neilb@xxxxxxxx are
vfs-discard-attr_attr_flag.patch
vfs-simplify-seq_file-iteration-code-and-interface.patch
