From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 206093ABD99; Mon, 17 Aug 2026 14:44:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786977872; cv=none; b=eIlQoZltfgPnmWSlzIGCV6XMI3Dxs4KRfXOLDmR/3HWee1yQeL34rIWRnesoDAwtFEnUGTjXC687DzQCl2vbwGNHAI3nHH90q9wK8SUTSfUigkg+J5HOleelpzpQUvgulYcvV73lfMZhdvywgUgQGbjJw7vvlfvDNc0jXZ7hJ20= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786977872; c=relaxed/simple; bh=6ANojbVvJ1XsMcQdfNkCNgfYawGWgOnmwOTQ4kJzvyE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=vCa0nnGTaHebABxXm7vmPMHVvi4TY2msyrmCiYEdFqejx+ikWs5Ys4QOb7ByCfrM2Vkzm1f+KFRrbtOpFBKCiNaRtjj773ozO1hyszNc8Sb73NuOptqvRts4pjWJ5Ms8thefV/b3HwSle56pvlZ0VxQAqAhzwSBBTiCfxTFykgc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VhDcCJGZ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="VhDcCJGZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 601E61F000E9; Mon, 17 Aug 2026 14:44:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786977870; bh=JPwPftm3GTSUsZQRVmLwHbnP8HKWSjMAowNAHamKhXc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=VhDcCJGZqD7BAGkw+dIV0zwWN6ZC1nQdSrJL9huVC/CeN2+NBrS6WR9EJM/BTUv/E zi30UTHag4rPha8SBR3cZ95xODPNBxtElxqKlw/Vonek8PJK9p7ALWBhtqcKifsT6b 5C3aPcGmwDUWKgDsBw5iyBH6qU+CD9q1pz7Lg7zs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Filipe Manana , Dmitry Antipov , David Sterba , Sasha Levin Subject: [PATCH 6.12 022/181] btrfs: fix memory leak in btrfs_do_encoded_write() Date: Mon, 17 Aug 2026 15:31:56 +0200 Message-ID: <20260817132536.261230892@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132535.394764707@linuxfoundation.org> References: <20260817132535.394764707@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Antipov [ Upstream commit d2a4e4e626b2f4670b69b430c357f03f53eb6632 ] Local fuzzing of 6.12.94 has found the following memory leak: Unreferenced object 0xffff888018050a80 (size 64): comm "syz.0.17", pid 10297, jiffies 4294953601 hex dump (first 32 bytes): 00 10 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................ 10 0a 05 18 80 88 ff ff 10 0a 05 18 80 88 ff ff ................ backtrace (crc a8a6fc29): kmemleak_alloc_recursive include/linux/kmemleak.h:42 [inline] slab_post_alloc_hook mm/slub.c:4152 [inline] slab_alloc_node mm/slub.c:4197 [inline] __kmalloc_cache_noprof+0x168/0x2c0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:878 [inline] extent_changeset_alloc fs/btrfs/extent_io.h:207 [inline] qgroup_reserve_data+0x1c5/0x7d0 fs/btrfs/qgroup.c:4305 btrfs_qgroup_reserve_data+0x2e/0xb0 fs/btrfs/qgroup.c:4355 btrfs_do_encoded_write+0x92e/0x1040 fs/btrfs/inode.c:9746 btrfs_encoded_write fs/btrfs/file.c:1482 [inline] btrfs_do_write_iter+0x280/0x610 fs/btrfs/file.c:1507 btrfs_ioctl_encoded_write+0x3d6/0x490 fs/btrfs/ioctl.c:4738 btrfs_ioctl+0x6f9/0xc90 fs/btrfs/ioctl.c:-1 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0xbe/0x1a0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x77/0x7f Unreferenced object 0xffff888018050a00 (size 64): comm "syz.0.17", pid 10297, jiffies 4294953601 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 ff 0f 00 00 00 00 00 00 ................ 90 0a 05 18 80 88 ff ff 90 0a 05 18 80 88 ff ff ................ backtrace (crc cb5c9580): kmemleak_alloc_recursive include/linux/kmemleak.h:42 [inline] slab_post_alloc_hook mm/slub.c:4152 [inline] slab_alloc_node mm/slub.c:4197 [inline] __kmalloc_cache_noprof+0x168/0x2c0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] ulist_prealloc+0x9c/0x110 fs/btrfs/ulist.c:114 extent_changeset_prealloc fs/btrfs/extent_io.h:217 [inline] __set_extent_bit+0x16b/0x1a70 fs/btrfs/extent-io-tree.c:1086 set_record_extent_bits+0x50/0x90 fs/btrfs/extent-io-tree.c:1821 qgroup_reserve_data+0x274/0x7d0 fs/btrfs/qgroup.c:4312 btrfs_qgroup_reserve_data+0x2e/0xb0 fs/btrfs/qgroup.c:4355 btrfs_do_encoded_write+0x92e/0x1040 fs/btrfs/inode.c:9746 btrfs_encoded_write fs/btrfs/file.c:1482 [inline] btrfs_do_write_iter+0x280/0x610 fs/btrfs/file.c:1507 btrfs_ioctl_encoded_write+0x3d6/0x490 fs/btrfs/ioctl.c:4738 btrfs_ioctl+0x6f9/0xc90 fs/btrfs/ioctl.c:-1 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0xbe/0x1a0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fix this by freeing an extent changeset before returning from btrfs_do_encoded_write(). Fixes: 7c0c7269f7b5 ("btrfs: add BTRFS_IOC_ENCODED_WRITE") Reviewed-by: Filipe Manana Signed-off-by: Dmitry Antipov Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/inode.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index f60f8bf38dc50..ab7f19ca21457 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -9684,6 +9684,7 @@ ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from, } kvfree(folios); out: + extent_changeset_free(data_reserved); if (ret >= 0) iocb->ki_pos += encoded->len; return ret; -- 2.53.0