+ lib-iov_iter-fix-import_iovec_ubuf-iovec-management.patch added to mm-hotfixes-unstable branch

+ lib-iov_iter-fix-import_iovec_ubuf-iovec-management.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: lib/iov_iter: fix import_iovec_ubuf iovec management
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     lib-iov_iter-fix-import_iovec_ubuf-iovec-management.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-iov_iter-fix-import_iovec_ubuf-iovec-management.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Pavel Begunkov <asml.silence@gmail.com>
Subject: lib/iov_iter: fix import_iovec_ubuf iovec management
Date: Fri, 31 Jan 2025 14:13:15 +0000

import_iovec() says that it should always be fine to kfree the iovec
returned in @iovp regardless of the error code.  __import_iovec_ubuf()
never reallocates it and thus should clear the pointer even in cases when
copy_iovec_*() fail.

Link: https://lkml.kernel.org/r/378ae26923ffc20fd5e41b4360d673bf47b1775b.1738332461.git.asml.silence@gmail.com
Fixes: 3b2deb0e46da9 ("iov_iter: import single vector iovecs as ITER_UBUF")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/iov_iter.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/lib/iov_iter.c~lib-iov_iter-fix-import_iovec_ubuf-iovec-management
+++ a/lib/iov_iter.c
@@ -1428,6 +1428,8 @@ static ssize_t __import_iovec_ubuf(int t
 	struct iovec *iov = *iovp;
 	ssize_t ret;
 
+	*iovp = NULL;
+
 	if (compat)
 		ret = copy_compat_iovec_from_user(iov, uvec, 1);
 	else
@@ -1438,7 +1440,6 @@ static ssize_t __import_iovec_ubuf(int t
 	ret = import_ubuf(type, iov->iov_base, iov->iov_len, i);
 	if (unlikely(ret))
 		return ret;
-	*iovp = NULL;
 	return i->count;
 }
 
_

Patches currently in -mm which might be from asml.silence@gmail.com are

lib-iov_iter-fix-import_iovec_ubuf-iovec-management.patch