The quilt patch titled Subject: Squashfs: remove deprecated strncpy by not copying the string has been removed from the -mm tree. Its filename was squashfs-remove-deprecated-strncpy-by-not-copying-the-string.patch This patch was dropped because it was merged into the mm-nonmm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Phillip Lougher <phillip@xxxxxxxxxxxxxxx> Subject: Squashfs: remove deprecated strncpy by not copying the string Date: Wed, 3 Apr 2024 19:33:52 +0100 Squashfs copied the passed string (name) into a temporary buffer to ensure it was NUL-terminated. This however is completely unnecessary as the string is already NUL-terminated. So remove the deprecated strncpy() by completely removing the string copy. The background behind this unnecessary string copy is that it dates back to the days when Squashfs was an out of kernel patch. The code deliberately did not assume the string was NUL-terminated in case in future this changed (due to kernel changes). This would mean the out of tree patches would be broken but still compile OK. Link: https://lkml.kernel.org/r/20240403183352.391308-1-phillip@xxxxxxxxxxxxxxx Signed-off-by: Phillip Lougher <phillip@xxxxxxxxxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> Reviewed-by: Justin Stitt <justinstitt@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/squashfs/namei.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) --- a/fs/squashfs/namei.c~squashfs-remove-deprecated-strncpy-by-not-copying-the-string +++ a/fs/squashfs/namei.c @@ -62,27 +62,21 @@ */ static int get_dir_index_using_name(struct super_block *sb, u64 *next_block, int *next_offset, u64 index_start, - int index_offset, int i_count, const char *name, - int len) + int index_offset, int i_count, const char *name) { struct squashfs_sb_info *msblk = sb->s_fs_info; int i, length = 0, err; unsigned int size; struct squashfs_dir_index *index; - char *str; TRACE("Entered get_dir_index_using_name, i_count %d\n", i_count); - index = kmalloc(sizeof(*index) + SQUASHFS_NAME_LEN * 2 + 2, GFP_KERNEL); + index = kmalloc(sizeof(*index) + SQUASHFS_NAME_LEN + 1, GFP_KERNEL); if (index == NULL) { ERROR("Failed to allocate squashfs_dir_index\n"); goto out; } - str = &index->name[SQUASHFS_NAME_LEN + 1]; - strncpy(str, name, len); - str[len] = '\0'; - for (i = 0; i < i_count; i++) { err = squashfs_read_metadata(sb, index, &index_start, &index_offset, sizeof(*index)); @@ -101,7 +95,7 @@ static int get_dir_index_using_name(stru index->name[size] = '\0'; - if (strcmp(index->name, str) > 0) + if (strcmp(index->name, name) > 0) break; length = le32_to_cpu(index->index); @@ -153,7 +147,7 @@ static struct dentry *squashfs_lookup(st length = get_dir_index_using_name(dir->i_sb, &block, &offset, squashfs_i(dir)->dir_idx_start, squashfs_i(dir)->dir_idx_offset, - squashfs_i(dir)->dir_idx_cnt, name, len); + squashfs_i(dir)->dir_idx_cnt, name); while (length < i_size_read(dir)) { /* _ Patches currently in -mm which might be from phillip@xxxxxxxxxxxxxxx are