From: Miquel Raynal <miquel.raynal@bootlin.com>
To: Eric Kilmer <eric.kilmer@trailofbits.com>
Cc: u-boot@lists.denx.de, jmcosta944@gmail.com,
thomas.petazzoni@bootlin.com, trini@konsulko.com
Subject: Re: [PATCH 1/1] fs/squashfs: fix heap buffer overflow in sqfs_frag_lookup()
Date: Mon, 23 Feb 2026 09:42:19 +0100 [thread overview]
Message-ID: <87zf4zrgus.fsf@bootlin.com> (raw)
In-Reply-To: <20260220194808.1146082-2-eric.kilmer@trailofbits.com> (Eric Kilmer's message of "Fri, 20 Feb 2026 14:48:08 -0500")
On 20/02/2026 at 14:48:08 -05, Eric Kilmer <eric.kilmer@trailofbits.com> wrote:
> sqfs_frag_lookup() reads a 16-bit metadata block header whose lower
> 15 bits encode the data size. Unlike sqfs_read_metablock() in
> sqfs_inode.c, this function does not validate that the decoded size is
> within SQFS_METADATA_BLOCK_SIZE (8192). A malformed SquashFS image can
> set the size field to any value up to 32767, causing memcpy to write
> past the 8192-byte 'entries' heap buffer.
>
> Add the same bounds check used by sqfs_read_metablock(): reject any
> metadata block header with SQFS_METADATA_SIZE(header) exceeding
> SQFS_METADATA_BLOCK_SIZE.
>
> Found by fuzzing with libFuzzer + AddressSanitizer.
>
> Signed-off-by: Eric Kilmer <eric.kilmer@trailofbits.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Thanks!
Miquèl
next prev parent reply other threads:[~2026-02-23 10:02 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-20 19:48 [PATCH 0/1] fs/squashfs: fix heap buffer overflow in sqfs_frag_lookup() Eric Kilmer
2026-02-20 19:48 ` [PATCH 1/1] " Eric Kilmer
2026-02-23 8:42 ` Miquel Raynal [this message]
2026-02-23 20:28 ` Tom Rini
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