Eric Biederman pointed out that using .extra1 to pass ipc namespace looks like an ugly hack and there is a better solution. We can get the ipc_namespace using the .data field. Link: https://lore.kernel.org/lkml/87czib9g38.fsf@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ Fixes: 1f5c135ee509 ("ipc: Store ipc sysctls in the ipc namespace") Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> Signed-off-by: Alexey Gladkov <legion@xxxxxxxxxx> --- ipc/ipc_sysctl.c | 24 +++++++----------------- 1 file changed, 7 insertions(+), 17 deletions(-) diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c index d1d5204cf589..eb7ba8e0a355 100644 --- a/ipc/ipc_sysctl.c +++ b/ipc/ipc_sysctl.c @@ -19,16 +19,11 @@ static int proc_ipc_dointvec_minmax_orphans(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { - struct ipc_namespace *ns = table->extra1; - struct ctl_table ipc_table; + struct ipc_namespace *ns = + container_of(table->data, struct ipc_namespace, shm_rmid_forced); int err; - memcpy(&ipc_table, table, sizeof(ipc_table)); - - ipc_table.extra1 = SYSCTL_ZERO; - ipc_table.extra2 = SYSCTL_ONE; - - err = proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos); + err = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (err < 0) return err; @@ -55,15 +50,10 @@ static int proc_ipc_auto_msgmni(struct ctl_table *table, int write, static int proc_ipc_sem_dointvec(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { - struct ipc_namespace *ns = table->extra1; - struct ctl_table ipc_table; + struct ipc_namespace *ns = + container_of(table->data, struct ipc_namespace, sem_ctls); int ret, semmni; - memcpy(&ipc_table, table, sizeof(ipc_table)); - - ipc_table.extra1 = NULL; - ipc_table.extra2 = NULL; - semmni = ns->sem_ctls[3]; ret = proc_dointvec(table, write, buffer, lenp, ppos); @@ -131,6 +121,8 @@ static struct ctl_table ipc_sysctls[] = { .maxlen = sizeof(init_ipc_ns.shm_rmid_forced), .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax_orphans, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, }, { .procname = "msgmax", @@ -237,7 +229,6 @@ bool setup_ipc_sysctls(struct ipc_namespace *ns) } else if (tbl[i].data == &init_ipc_ns.shm_rmid_forced) { tbl[i].data = &ns->shm_rmid_forced; - tbl[i].extra1 = ns; } else if (tbl[i].data == &init_ipc_ns.msg_ctlmax) { tbl[i].data = &ns->msg_ctlmax; @@ -250,7 +241,6 @@ bool setup_ipc_sysctls(struct ipc_namespace *ns) } else if (tbl[i].data == &init_ipc_ns.sem_ctls) { tbl[i].data = &ns->sem_ctls; - tbl[i].extra1 = ns; #ifdef CONFIG_CHECKPOINT_RESTORE } else if (tbl[i].data == &init_ipc_ns.ids[IPC_SEM_IDS].next_id) { tbl[i].data = &ns->ids[IPC_SEM_IDS].next_id; -- 2.33.3
