Message ID | 1529317698-16575-6-git-send-email-longman@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Hi Waiman, Thank you for the patch! Yet something to improve: [auto build test ERROR on linus/master] [also build test ERROR on v4.18-rc1 next-20180618] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Waiman-Long/ipc-IPCMNI-limit-check-for-mni-increase-that-limit/20180618-183206 config: i386-randconfig-x013-201824 (attached as .config) compiler: gcc-7 (Debian 7.3.0-16) 7.3.0 reproduce: # save the attached .config to linux build tree make ARCH=i386 All errors (new ones prefixed by >>): In file included from ipc/mqueue.c:43:0: ipc/util.h: In function 'sem_check_semmni': >> ipc/util.h:251:54: error: 'ipcmni_max' undeclared (first use in this function); did you mean 'icmp_mib'? return ((ns->sem_ctls[3] < 0) || (ns->sem_ctls[3] > ipcmni_max)) ^~~~~~~~~~ icmp_mib ipc/util.h:251:54: note: each undeclared identifier is reported only once for each function it appears in -- In file included from ipc/msgutil.c:22:0: ipc/util.h: In function 'sem_check_semmni': >> ipc/util.h:251:54: error: 'ipcmni_max' undeclared (first use in this function); did you mean 'pci_iomap'? return ((ns->sem_ctls[3] < 0) || (ns->sem_ctls[3] > ipcmni_max)) ^~~~~~~~~~ pci_iomap ipc/util.h:251:54: note: each undeclared identifier is reported only once for each function it appears in vim +251 ipc/util.h 239 240 struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id); 241 int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids, 242 const struct ipc_ops *ops, struct ipc_params *params); 243 void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids, 244 void (*free)(struct ipc_namespace *, struct kern_ipc_perm *)); 245 246 static inline int sem_check_semmni(struct ipc_namespace *ns) { 247 /* 248 * Check semmni range [0, ipcmni_max] 249 * semmni is the last element of sem_ctls[4] array 250 */ > 251 return ((ns->sem_ctls[3] < 0) || (ns->sem_ctls[3] > ipcmni_max)) 252 ? -ERANGE : 0; 253 } 254 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
Hi Waiman, Thank you for the patch! Yet something to improve: [auto build test ERROR on linus/master] [also build test ERROR on v4.18-rc1 next-20180618] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Waiman-Long/ipc-IPCMNI-limit-check-for-mni-increase-that-limit/20180618-183206 config: i386-randconfig-a0-06181851 (attached as .config) compiler: gcc-4.9 (Debian 4.9.4-2) 4.9.4 reproduce: # save the attached .config to linux build tree make ARCH=i386 All errors (new ones prefixed by >>): In file included from ipc/mqueue.c:43:0: ipc/util.h: In function 'sem_check_semmni': >> ipc/util.h:251:54: error: 'ipcmni_max' undeclared (first use in this function) return ((ns->sem_ctls[3] < 0) || (ns->sem_ctls[3] > ipcmni_max)) ^ ipc/util.h:251:54: note: each undeclared identifier is reported only once for each function it appears in vim +/ipcmni_max +251 ipc/util.h 239 240 struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id); 241 int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids, 242 const struct ipc_ops *ops, struct ipc_params *params); 243 void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids, 244 void (*free)(struct ipc_namespace *, struct kern_ipc_perm *)); 245 246 static inline int sem_check_semmni(struct ipc_namespace *ns) { 247 /* 248 * Check semmni range [0, ipcmni_max] 249 * semmni is the last element of sem_ctls[4] array 250 */ > 251 return ((ns->sem_ctls[3] < 0) || (ns->sem_ctls[3] > ipcmni_max)) 252 ? -ERANGE : 0; 253 } 254 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index eded671d..e98d967 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -39,6 +39,7 @@ show up in /proc/sys/kernel: - hung_task_check_count - hung_task_timeout_secs - hung_task_warnings +- ipcmni_compat - kexec_load_disabled - kptr_restrict - l2cr [ PPC only ] @@ -374,6 +375,20 @@ This file shows up if CONFIG_DETECT_HUNG_TASK is enabled. ============================================================== +ipcmni_compat: + +A boolean flag to control range checking behavior of msgmni, shmmni +and the mni portion of sem. + +0: Range limits will be strictly enforced and error will be returned + if limits are exceeded. +1: Range limits will only be enforced internally and no error will be + returned if the upper limit is exceeded. This compatibility behavior + can only be selected if the ipcmni_extend kernel boot parameter is + not specified. + +============================================================== + kexec_load_disabled: A toggle indicating if the kexec_load syscall has been disabled. This diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c index d9ac6ca..5c0eac4 100644 --- a/ipc/ipc_sysctl.c +++ b/ipc/ipc_sysctl.c @@ -18,6 +18,8 @@ #include <linux/msg.h> #include "util.h" +static int ipcmni_compat; + static void *get_ipc(struct ctl_table *table) { char *which = table->data; @@ -108,6 +110,25 @@ static int proc_ipc_sem_dointvec(struct ctl_table *table, int write, return ret; } +static int proc_ipcmni_compat_minmax(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + + if (ret) + return ret; + + /* + * ipcmni_compat can only be set if !ipcmni_extend. + */ + if (ipcmni_compat && ipc_mni_extended) { + ipcmni_compat = 0; + return -EINVAL; + } + ipcmni_max = ipcmni_compat ? INT_MAX : ipc_mni; + return 0; +} + #else #define proc_ipc_doulongvec_minmax NULL #define proc_ipc_dointvec NULL @@ -115,11 +136,13 @@ static int proc_ipc_sem_dointvec(struct ctl_table *table, int write, #define proc_ipc_dointvec_minmax_orphans NULL #define proc_ipc_auto_msgmni NULL #define proc_ipc_sem_dointvec NULL +#define proc_ipcmni_compat_minmax NULL #endif static int zero; static int one = 1; static int int_max = INT_MAX; +int ipcmni_max = IPCMNI; int ipc_mni = IPCMNI; int ipc_mni_shift = IPCMNI_SHIFT; bool ipc_mni_extended; @@ -146,7 +169,7 @@ static int proc_ipc_sem_dointvec(struct ctl_table *table, int write, .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, - .extra2 = &ipc_mni, + .extra2 = &ipcmni_max, }, { .procname = "shm_rmid_forced", @@ -173,7 +196,7 @@ static int proc_ipc_sem_dointvec(struct ctl_table *table, int write, .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, - .extra2 = &ipc_mni, + .extra2 = &ipcmni_max, }, { .procname = "auto_msgmni", @@ -229,6 +252,19 @@ static int proc_ipc_sem_dointvec(struct ctl_table *table, int write, .extra2 = &int_max, }, #endif + /* + * Unlike other IPC sysctl parameters above, the following sysctl + * parameter is global and affect behavior for all the namespaces. + */ + { + .procname = "ipcmni_compat", + .data = &ipcmni_compat, + .maxlen = sizeof(ipcmni_compat), + .mode = 0644, + .proc_handler = proc_ipcmni_compat_minmax, + .extra1 = &zero, + .extra2 = &one, + }, {} }; @@ -251,7 +287,7 @@ static int __init ipc_sysctl_init(void) static int __init ipc_mni_extend(char *str) { - ipc_mni = IPCMNI_EXTEND; + ipc_mni = ipcmni_max = IPCMNI_EXTEND; ipc_mni_shift = IPCMNI_EXTEND_SHIFT; ipc_mni_extended = true; pr_info("IPCMNI extended to %d.\n", ipc_mni); diff --git a/ipc/util.h b/ipc/util.h index 62b6247..dde5014 100644 --- a/ipc/util.h +++ b/ipc/util.h @@ -29,6 +29,7 @@ #ifdef CONFIG_SYSVIPC_SYSCTL extern int ipc_mni; extern int ipc_mni_shift; +extern int ipcmni_max; extern bool ipc_mni_extended; #define SEQ_SHIFT ipc_mni_shift @@ -244,10 +245,10 @@ void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids, static inline int sem_check_semmni(struct ipc_namespace *ns) { /* - * Check semmni range [0, ipc_mni] + * Check semmni range [0, ipcmni_max] * semmni is the last element of sem_ctls[4] array */ - return ((ns->sem_ctls[3] < 0) || (ns->sem_ctls[3] > ipc_mni)) + return ((ns->sem_ctls[3] < 0) || (ns->sem_ctls[3] > ipcmni_max)) ? -ERANGE : 0; }
With strict range limit enforcement of msgmni, shmmni and sem, it is possible that some existing applications that set those values to above 32k may fail. To help users to work around this potential problem, a new boolean ipcmni_compat sysctl is added to provide the old beahavior for compatibility when it is set to 1. In other word, the limit will then be enforced internally but no error will be reported. This compatibility mode can only be enabled if the ipcmni_extend kernel boot parameter is not specified. The sysctl documentation is also updated accordingly. Signed-off-by: Waiman Long <longman@redhat.com> --- Documentation/sysctl/kernel.txt | 15 +++++++++++++++ ipc/ipc_sysctl.c | 42 ++++++++++++++++++++++++++++++++++++++--- ipc/util.h | 5 +++-- 3 files changed, 57 insertions(+), 5 deletions(-)