The patch titled ipc: save the ipc namespace while reading proc files has been removed from the -mm tree. Its filename was ipc-save-the-ipc-namespace-while-reading-proc-files.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ Subject: ipc: save the ipc namespace while reading proc files From: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> The problem we were assuming that current->nsproxy->ipc_ns would never change while someone has our file in /proc/sysvipc/ file open. Given that this can change with both unshare and by passing the file descriptor to another process that assumption is occasionally wrong. Therefore this patch causes /proc/sysvipc/* to cache the namespace and increment it's count when we open the file and to decrement the count when we close the file, ensuring consistent operation with no surprises. Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> Cc: Serge E. Hallyn <serue@xxxxxxxxxx> Cc: Herbert Poetzl <herbert@xxxxxxxxxxxx> Cc: Kirill Korotaev <dev@xxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- ipc/util.c | 58 +++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 45 insertions(+), 13 deletions(-) diff -puN ipc/util.c~ipc-save-the-ipc-namespace-while-reading-proc-files ipc/util.c --- a/ipc/util.c~ipc-save-the-ipc-namespace-while-reading-proc-files +++ a/ipc/util.c @@ -738,14 +738,20 @@ int ipc_parse_version (int *cmd) #endif /* __ARCH_WANT_IPC_PARSE_VERSION */ #ifdef CONFIG_PROC_FS +struct ipc_proc_iter { + struct ipc_namespace *ns; + struct ipc_proc_iface *iface; +}; + static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos) { - struct ipc_proc_iface *iface = s->private; + struct ipc_proc_iter *iter = s->private; + struct ipc_proc_iface *iface = iter->iface; struct kern_ipc_perm *ipc = it; loff_t p; struct ipc_ids *ids; - ids = current->nsproxy->ipc_ns->ids[iface->ids]; + ids = iter->ns->ids[iface->ids]; /* If we had an ipc id locked before, unlock it */ if (ipc && ipc != SEQ_START_TOKEN) @@ -772,12 +778,13 @@ static void *sysvipc_proc_next(struct se */ static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos) { - struct ipc_proc_iface *iface = s->private; + struct ipc_proc_iter *iter = s->private; + struct ipc_proc_iface *iface = iter->iface; struct kern_ipc_perm *ipc; loff_t p; struct ipc_ids *ids; - ids = current->nsproxy->ipc_ns->ids[iface->ids]; + ids = iter->ns->ids[iface->ids]; /* * Take the lock - this will be released by the corresponding @@ -806,21 +813,23 @@ static void *sysvipc_proc_start(struct s static void sysvipc_proc_stop(struct seq_file *s, void *it) { struct kern_ipc_perm *ipc = it; - struct ipc_proc_iface *iface = s->private; + struct ipc_proc_iter *iter = s->private; + struct ipc_proc_iface *iface = iter->iface; struct ipc_ids *ids; /* If we had a locked segment, release it */ if (ipc && ipc != SEQ_START_TOKEN) ipc_unlock(ipc); - ids = current->nsproxy->ipc_ns->ids[iface->ids]; + ids = iter->ns->ids[iface->ids]; /* Release the lock we took in start() */ mutex_unlock(&ids->mutex); } static int sysvipc_proc_show(struct seq_file *s, void *it) { - struct ipc_proc_iface *iface = s->private; + struct ipc_proc_iter *iter = s->private; + struct ipc_proc_iface *iface = iter->iface; if (it == SEQ_START_TOKEN) return seq_puts(s, iface->header); @@ -835,22 +844,45 @@ static struct seq_operations sysvipc_pro .show = sysvipc_proc_show, }; -static int sysvipc_proc_open(struct inode *inode, struct file *file) { +static int sysvipc_proc_open(struct inode *inode, struct file *file) +{ int ret; struct seq_file *seq; + struct ipc_proc_iter *iter; + + ret = -ENOMEM; + iter = kmalloc(sizeof(*iter), GFP_KERNEL); + if (!iter) + goto out; ret = seq_open(file, &sysvipc_proc_seqops); - if (!ret) { - seq = file->private_data; - seq->private = PDE(inode)->data; - } + if (ret) + goto out_kfree; + + seq = file->private_data; + seq->private = iter; + + iter->iface = PDE(inode)->data; + iter->ns = get_ipc_ns(current->nsproxy->ipc_ns); +out: return ret; +out_kfree: + kfree(iter); + goto out; +} + +static int sysvipc_proc_release(struct inode *inode, struct file *file) +{ + struct seq_file *seq = file->private_data; + struct ipc_proc_iter *iter = seq->private; + put_ipc_ns(iter->ns); + return seq_release_private(inode, file); } static struct file_operations sysvipc_proc_fops = { .open = sysvipc_proc_open, .read = seq_read, .llseek = seq_lseek, - .release = seq_release, + .release = sysvipc_proc_release, }; #endif /* CONFIG_PROC_FS */ _ Patches currently in -mm which might be from ebiederm@xxxxxxxxxxxx are origin.patch powerpc-rtas-msi-support.patch fix-i-oat-for-kexec.patch bugfixes-pci-devices-get-assigned-redundant-irqs.patch git-v9fs.patch x86_64-irq-simplfy-__assign_irq_vector.patch x86_64-irq-handle-irqs-pending-in-irr-during-irq-migration.patch x86_64-survive-having-no-irq-mapping-for-a-vector-fix.patch procfs-fix-race-between-proc_readdir-and-remove_proc_entry.patch procfs-fix-race-between-proc_readdir-and-remove_proc_entry-fix.patch clone-flag-clone_parent_tidptr-leaves-invalid-results-in-memory.patch fix-rmmod-read-write-races-in-proc-entries.patch allow-access-to-proc-pid-fd-after-setuid.patch allow-access-to-proc-pid-fd-after-setuid-fix.patch allow-access-to-proc-pid-fd-after-setuid-update.patch allow-access-to-proc-pid-fd-after-setuid-update-2.patch shm-make-sysv-ipc-shared-memory-use-stacked-files.patch i386-apic-clean-up-the-apic-code.patch i386-rework-local-apic-timer-calibration.patch i386-prepare-nmi-watchdog-for-dynticks.patch edac-k8-driver-coding-tidy.patch sched2-sched-domain-sysctl-use-ctl_unnumbered.patch mm-implement-swap-prefetching-use-ctl_unnumbered.patch readahead-sysctl-parameters-use-ctl_unnumbered.patch sysctl-x25-remove-unnecessary-insert_at_head-from-register_sysctl_table.patch sysctl-move-ctl_sunrpc-to-sysctlh-where-it-belongs.patch sysctl-sunrpc-remove-unnecessary-insert_at_head-flag.patch sysctl-sunrpc-dont-unnecessarily-set-ctl_table-de.patch sysctl-rose-remove-unnecessary-insert_at_head-flag.patch sysctl-netrom-remove-unnecessary-insert_at_head-flag.patch sysctl-llc-remove-unnecessary-insert_at_head-flag.patch sysctl-ipx-remove-unnecessary-insert_at_head-flag.patch sysctl-decnet-remove-unnecessary-insert_at_head-flag.patch sysctl-dccp-remove-unnecessary-insert_at_head-flag.patch sysctl-ax25-remove-unnecessary-insert_at_head-flag.patch sysctl-atalk-remove-unnecessary-insert_at_head-flag.patch sysctl-scsi-remove-unnecessary-insert_at_head-flag.patch sysctl-md-remove-unnecessary-insert_at_head-flag.patch sysctl-mac_hid-remove-unnecessary-insert_at_head-flag.patch sysctl-ipmi-remove-unnecessary-insert_at_head-flag.patch sysctl-cdrom-remove-unnecessary-insert_at_head-flag.patch sysctl-cdrom-dont-set-de-owner.patch sysctl-move-ctl_pm-into-sysctlh-where-it-belongs.patch sysctl-frv-pm-remove-unnecessary-insert_at_head-flag.patch sysctl-move-ctl_frv-into-sysctlh-where-it-belongs.patch sysctl-frv-remove-unnecessary-insert_at_head-flag.patch sysctl-c99-convert-arch-frv-kernel-pmc.patch sysctl-c99-convert-arch-frv-kernel-sysctlc.patch sysctl-sn-remove-sysctl-abi-breakage.patch sysctl-c99-convert-arch-ia64-sn-kernel-xpc_mainc.patch sysctl-c99-convert-arch-ia64-kernel-perfmon-and-remove-abi-breakage.patch sysctl-mips-au1000-remove-sys_sysctl-support.patch sysctl-c99-convert-the-ctl_tables-in-arch-mips-au1000-common-powerc.patch sysctl-c99-convert-arch-mips-lasat-sysctlc-and-remove-abi-breakage.patch sysctl-s390-move-sysctl-definitions-to-sysctlh.patch sysctl-s390-remove-unnecessary-use-of-insert_at_head.patch sysctl-c99-convert-ctl_tables-in-arch-powerpc-kernel-idlec.patch sysctl-c99-convert-ctl_tables-entries-in-arch-ppc-kernel-ppc_htabc.patch sysctl-c99-convert-arch-sh64-kernel-trapsc-and-remove-abi-breakage.patch sysctl-x86_64-remove-unnecessary-use-of-insert_at_head.patch sysctl-c99-convert-ctl_tables-in-arch-x86_64-ia32-ia32_binfmtc.patch sysctl-c99-convert-ctl_tables-in-arch-x86_64-kernel-vsyscallc.patch sysctl-c99-convert-ctl_tables-in-arch-x86_64-mm-initc.patch sysctl-remove-sys_sysctl-support-from-the-hpet-timer-driver.patch sysctl-remove-sys_sysctl-support-from-drivers-char-rtcc.patch sysctl-register-the-sysctl-number-used-by-the-arlan-driver.patch sysctl-c99-convert-ctl_tables-in-drivers-parport-procfsc.patch sysctl-c99-convert-ctl_tables-in-drivers-parport-procfsc-fix.patch sysctl-c99-convert-coda-ctl_tables-and-remove-binary-sysctls.patch sysctl-c99-convert-ctl_tables-in-ntfs-and-remove-sys_sysctl-support.patch sysctl-c99-convert-ctl_tables-in-ntfs-and-remove-sys_sysctl-support-fix.patch sysctl-register-the-ocfs2-sysctl-numbers.patch sysctl-move-init_irq_proc-into-init-main-where-it-belongs.patch sysctl-move-utsname-sysctls-to-their-own-file.patch sysctl-move-utsname-sysctls-to-their-own-file-fix-2.patch sysctl-move-sysv-ipc-sysctls-to-their-own-file.patch sysctl-move-sysv-ipc-sysctls-to-their-own-file-fix.patch sysctl-move-sysv-ipc-sysctls-to-their-own-file-fix-2.patch sysctl-create-sys-fs-binfmt_misc-as-an-ordinary-sysctl-entry.patch sysctl-create-sys-fs-binfmt_misc-as-an-ordinary-sysctl-entry-warning-fix.patch sysctl-remove-support-for-ctl_any.patch sysctl-remove-support-for-directory-strategy-routines.patch sysctl-remove-insert_at_head-from-register_sysctl.patch sysctl-remove-insert_at_head-from-register_sysctl-fix.patch sysctl-factor-out-sysctl_head_next-from-do_sysctl.patch sysctl-factor-out-sysctl_head_next-from-do_sysctl-warning-fix.patch sysctl-allow-sysctl_perm-to-be-called-from-outside-of-sysctlc.patch sysctl-reimplement-the-sysctl-proc-support.patch sysctl-reimplement-the-sysctl-proc-support-fix.patch sysctl-reimplement-the-sysctl-proc-support-warning-fix.patch sysctl-reimplement-the-sysctl-proc-support-fix-2.patch sysctl-reimplement-the-sysctl-proc-support-fix-3.patch sysctl-reimplement-the-sysctl-proc-support-fix-4.patch sysctl-add-a-parent-entry-to-ctl_table-and-set-the-parent-entry.patch sysctl-add-a-parent-entry-to-ctl_table-and-set-the-parent-entry-fix.patch sysctl-remove-the-proc_dir_entry-member-for-the-sysctl-tables.patch sysctl-remove-the-proc_dir_entry-member-for-the-sysctl-tables-fix.patch sysctl-remove-the-proc_dir_entry-member-for-the-sysctl-tables-fix-2.patch sysctl-remove-the-proc_dir_entry-member-for-the-sysctl-tables-ntfs-fix.patch sysctl-fix-the-selinux_sysctl_get_sid.patch selinux-enhance-selinux-to-always-ignore-private-inodes.patch sysctl-hide-the-sysctl-proc-inodes-from-selinux.patch vdso-print-fatal-signals-use-ctl_unnumbered.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html