The patch titled Subject: squashfs: fix buffer release race condition in readahead code has been added to the -mm mm-hotfixes-unstable branch. Its filename is squashfs-fix-buffer-release-race-condition-in-readahead-code.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

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------------------------------------------------------ From: Phillip Lougher phillip@squashfs.org.uk Subject: squashfs: fix buffer release race condition in readahead code Date: Thu, 20 Oct 2022 23:36:16 +0100

Fix a buffer release race condition, where the error value was used after release.

Link: https://lkml.kernel.org/r/20221020223616.7571-4-phillip@squashfs.org.uk Fixes: b09a7a036d20 ("squashfs: support reading fragments in readahead call") Signed-off-by: Phillip Lougher phillip@squashfs.org.uk Cc: stable@vger.kernel.org Cc: Bagas Sanjaya bagasdotme@gmail.com Cc: Dimitri John Ledkov dimitri.ledkov@canonical.com Cc: Hsin-Yi Wang hsinyi@chromium.org Cc: Mirsad Goran Todorovac mirsad.todorovac@alu.unizg.hr Cc: Slade Watkins srw@sladewatkins.net Cc: Thorsten Leemhuis regressions@leemhuis.info Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

fs/squashfs/file.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/fs/squashfs/file.c~squashfs-fix-buffer-release-race-condition-in-readahead-code +++ a/fs/squashfs/file.c @@ -506,8 +506,9 @@ static int squashfs_readahead_fragment(s squashfs_i(inode)->fragment_size); struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info; unsigned int n, mask = (1 << (msblk->block_log - PAGE_SHIFT)) - 1; + int error = buffer->error;

- if (buffer->error) + if (error) goto out;

expected += squashfs_i(inode)->fragment_offset; @@ -529,7 +530,7 @@ static int squashfs_readahead_fragment(s

out: squashfs_cache_put(buffer); - return buffer->error; + return error; }

static void squashfs_readahead(struct readahead_control *ractl) _

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

squashfs-fix-read-regression-introduced-in-readahead-code.patch squashfs-fix-extending-readahead-beyond-end-of-file.patch squashfs-fix-buffer-release-race-condition-in-readahead-code.patch