6.12-stable review patch. If anyone has any objections, please let me know.
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From: Namjae Jeon linkinjeon@kernel.org
commit 84d2d1641b71dec326e8736a749b7ee76a9599fc upstream.
If smb_lock->zero_len has value, ->llist of smb_lock is not delete and flock is old one. It will cause use-after-free on error handling routine.
Cc: stable@vger.kernel.org Reported-by: Norbert Szetei norbert@doyensec.com Tested-by: Norbert Szetei norbert@doyensec.com Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/server/smb2pdu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -7441,13 +7441,13 @@ out_check_cl: }
no_check_cl: + flock = smb_lock->fl; + list_del(&smb_lock->llist); + if (smb_lock->zero_len) { err = 0; goto skip; } - - flock = smb_lock->fl; - list_del(&smb_lock->llist); retry: rc = vfs_lock_file(filp, smb_lock->cmd, flock, NULL); skip: