From 44e3876d268be49ee810481ee3c95d8d650bf22e Mon Sep 17 00:00:00 2001 From: Philipp Stanner Date: Tue, 7 Nov 2023 07:44:16 +0900 Subject: [PATCH] fs/nilfs2: use standard array-copy-function ioctl.c utilizes memdup_user() to copy a userspace array. An overflow check is performed manually before the function's invocation. The new function memdup_array_user() standardizes copying userspace arrays, thus, improving readability by making it more clear that an array is being copied. Additionally, it also performs an overflow check. Remove the (now redundant) manual overflow-check and replace memdup_user() with memdup_array_user(). In addition, improve the grammar of the comment above memdup_array_user(). Link: https://lkml.kernel.org/r/20231106224416.3055-1-konishi.ryusuke@gmail.com Signed-off-by: Philipp Stanner Link: https://lkml.kernel.org/r/20231103184831.99406-2-pstanner@redhat.com Signed-off-by: Ryusuke Konishi Suggested-by: Dave Airlie Signed-off-by: Andrew Morton --- fs/nilfs2/ioctl.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c index 40ffade49f38..cfb6aca5ec38 100644 --- a/fs/nilfs2/ioctl.c +++ b/fs/nilfs2/ioctl.c @@ -872,16 +872,14 @@ static int nilfs_ioctl_clean_segments(struct inode *inode, struct file *filp, nsegs = argv[4].v_nmembs; if (argv[4].v_size != argsz[4]) goto out; - if (nsegs > UINT_MAX / sizeof(__u64)) - goto out; /* * argv[4] points to segment numbers this ioctl cleans. We - * use kmalloc() for its buffer because memory used for the - * segment numbers is enough small. + * use kmalloc() for its buffer because the memory used for the + * segment numbers is small enough. */ - kbufs[4] = memdup_user((void __user *)(unsigned long)argv[4].v_base, - nsegs * sizeof(__u64)); + kbufs[4] = memdup_array_user((void __user *)(unsigned long)argv[4].v_base, + nsegs, sizeof(__u64)); if (IS_ERR(kbufs[4])) { ret = PTR_ERR(kbufs[4]); goto out;