Re: [PATCH 7/7] sysvipc_find_ipc should increase position index
On 5/5/20 7:13 PM, Andreas Schwab wrote: > I think this is causing this bug (seen on 5.6.8): thank you for reporting, yes, you are right, it's my fault patch incorrectly updated *new_pos in case of found entry > # ipcs -q > > -- Message Queues > keymsqid owner perms used-bytes messages > 0x7c982867 3 root 64400 > 0x7c982867 3 root 64400 > 0x7c982867 3 root 64400 > 0x7c982867 3 root 64400 Thank you, Vasily Averin
Re: [PATCH 7/7] sysvipc_find_ipc should increase position index
I think this is causing this bug (seen on 5.6.8): # ipcs -q -- Message Queues keymsqid owner perms used-bytes messages # ipcmk -Q Message queue id: 0 # ipcs -q -- Message Queues keymsqid owner perms used-bytes messages 0x82db8127 0 root 64400 # ipcmk -Q Message queue id: 1 # ipcs -q -- Message Queues keymsqid owner perms used-bytes messages 0x82db8127 0 root 64400 0x76d1fb2a 1 root 64400 # ipcrm -q 0 # ipcs -q -- Message Queues keymsqid owner perms used-bytes messages 0x76d1fb2a 1 root 64400 0x76d1fb2a 1 root 64400 # ipcmk -Q Message queue id: 2 # ipcrm -q 2 # ipcs -q -- Message Queues keymsqid owner perms used-bytes messages 0x76d1fb2a 1 root 64400 0x76d1fb2a 1 root 64400 # ipcmk -Q Message queue id: 3 # ipcrm -q 1 # ipcs -q -- Message Queues keymsqid owner perms used-bytes messages 0x7c982867 3 root 64400 0x7c982867 3 root 64400 0x7c982867 3 root 64400 0x7c982867 3 root 64400 As you can see, whenever an IPC item with a low id is deleted, the items with higher ids are duplicated, as if filling a hole. Andreas. -- Andreas Schwab, SUSE Labs, sch...@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different."
