The patch titled Subject: squashfs: fix memory leak in squashfs_fill_super has been added to the -mm mm-hotfixes-unstable branch. Its filename is squashfs-fix-memory-leak-in-squashfs_fill_super.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

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

Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days

------------------------------------------------------ From: Phillip Lougher phillip@squashfs.org.uk Subject: squashfs: fix memory leak in squashfs_fill_super Date: Mon, 11 Aug 2025 23:37:40 +0100

If sb_min_blocksize returns 0, squashfs_fill_super exits without freeing allocated memory (sb->s_fs_info).

Fix this by moving the call to sb_min_blocksize to before memory is allocated.

Link: https://lkml.kernel.org/r/20250811223740.110392-1-phillip@squashfs.org.uk Fixes: 734aa85390ea ("Squashfs: check return result of sb_min_blocksize") Signed-off-by: Phillip Lougher phillip@squashfs.org.uk Reported-by: Scott GUO scottzhguo@tencent.com Closes: https://lore.kernel.org/all/20250811061921.3807353-1-scott_gzh@163.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

fs/squashfs/super.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)

--- a/fs/squashfs/super.c~squashfs-fix-memory-leak-in-squashfs_fill_super +++ a/fs/squashfs/super.c @@ -187,10 +187,15 @@ static int squashfs_fill_super(struct su unsigned short flags; unsigned int fragments; u64 lookup_table_start, xattr_id_table_start, next_table; - int err; + int err, devblksize = sb_min_blocksize(sb, SQUASHFS_DEVBLK_SIZE);

TRACE("Entered squashfs_fill_superblock\n");

+ if (!devblksize) { + errorf(fc, "squashfs: unable to set blocksize\n"); + return -EINVAL; + } + sb->s_fs_info = kzalloc(sizeof(*msblk), GFP_KERNEL); if (sb->s_fs_info == NULL) { ERROR("Failed to allocate squashfs_sb_info\n"); @@ -201,12 +206,7 @@ static int squashfs_fill_super(struct su

msblk->panic_on_errors = (opts->errors == Opt_errors_panic);

- msblk->devblksize = sb_min_blocksize(sb, SQUASHFS_DEVBLK_SIZE); - if (!msblk->devblksize) { - errorf(fc, "squashfs: unable to set blocksize\n"); - return -EINVAL; - } - + msblk->devblksize = devblksize; msblk->devblksize_log2 = ffz(~msblk->devblksize);

mutex_init(&msblk->meta_index_mutex); _

Patches currently in -mm which might be from phillip@squashfs.org.uk are

squashfs-fix-memory-leak-in-squashfs_fill_super.patch