In construct_alloc_key(), up_write() is called in the error path if __key_link_begin() fails, but this is incorrect as __key_link_begin() only returns with the nominated keyring locked if it returns successfully. Without this patch, you might see the following in dmesg: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- mount.cifs/5769 is trying to release lock (&key->sem) at: [<ffffffff81201159>] request_key_and_link+0x263/0x3fc but there are no more locks to release! other info that might help us debug this: 3 locks held by mount.cifs/5769: #0: (&type->s_umount_key#41/1){+.+.+.}, at: [<ffffffff81131321>] sget+0x278/0x3e7 #1: (&ret_buf->session_mutex){+.+.+.}, at: [<ffffffffa0258e59>] cifs_get_smb_ses+0x35a/0x443 [cifs] #2: (root_key_user.cons_lock){+.+.+.}, at: [<ffffffff81201000>] request_key_and_link+0x10a/0x3fc stack backtrace: Pid: 5769, comm: mount.cifs Not tainted 2.6.37-rc6+ #1 Call Trace: [<ffffffff81201159>] ? request_key_and_link+0x263/0x3fc [<ffffffff81081601>] print_unlock_inbalance_bug+0xca/0xd5 [<ffffffff81083248>] lock_release_non_nested+0xc1/0x263 [<ffffffff81201159>] ? request_key_and_link+0x263/0x3fc [<ffffffff81201159>] ? request_key_and_link+0x263/0x3fc [<ffffffff81083567>] lock_release+0x17d/0x1a4 [<ffffffff81073f45>] up_write+0x23/0x3b [<ffffffff81201159>] request_key_and_link+0x263/0x3fc [<ffffffffa026fe9e>] ? cifs_get_spnego_key+0x61/0x21f [cifs] [<ffffffff812013c5>] request_key+0x41/0x74 [<ffffffffa027003d>] cifs_get_spnego_key+0x200/0x21f [cifs] [<ffffffffa026e296>] CIFS_SessSetup+0x55d/0x1273 [cifs] [<ffffffffa02589e1>] cifs_setup_session+0x90/0x1ae [cifs] [<ffffffffa0258e7e>] cifs_get_smb_ses+0x37f/0x443 [cifs] [<ffffffffa025a9e3>] cifs_mount+0x1aa1/0x23f3 [cifs] [<ffffffff8111fd94>] ? alloc_debug_processing+0xdb/0x120 [<ffffffffa027002c>] ? cifs_get_spnego_key+0x1ef/0x21f [cifs] [<ffffffffa024cc71>] cifs_do_mount+0x165/0x2b3 [cifs] [<ffffffff81130e72>] vfs_kern_mount+0xaf/0x1dc [<ffffffff81131007>] do_kern_mount+0x4d/0xef [<ffffffff811483b9>] do_mount+0x6f4/0x733 [<ffffffff8114861f>] sys_mount+0x88/0xc2 [<ffffffff8100ac42>] system_call_fastpath+0x16/0x1b Reported-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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.. | ||
apparmor | ||
integrity/ima | ||
keys | ||
selinux | ||
smack | ||
tomoyo | ||
Kconfig | ||
Makefile | ||
capability.c | ||
commoncap.c | ||
device_cgroup.c | ||
inode.c | ||
lsm_audit.c | ||
min_addr.c | ||
security.c |