commit f9c82a4ea89c3 ("Increase size of ucounts to atomic_long_t") changed the data type of ucounts/ucounts_max to long, but missed to adjust a few other places. This is noticeable on big endian platforms from user space because the /proc/sys/user/max_*_names files all contain 0. v4 - Made the min and max constants long so the sysctl values are actually settable on little endian machines. -- EWB Fixes: f9c82a4ea89c ("Increase size of ucounts to atomic_long_t") Signed-off-by: Sven Schnelle <svens@xxxxxxxxxxxxx> Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx> Tested-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx> Acked-by: Alexey Gladkov <legion@xxxxxxxxxx> v1: https://lkml.kernel.org/r/20210721115800.910778-1-svens@xxxxxxxxxxxxx v2: https://lkml.kernel.org/r/20210721125233.1041429-1-svens@xxxxxxxxxxxxx v3: https://lkml.kernel.org/r/20210730062854.3601635-1-svens@xxxxxxxxxxxxx Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> --- Thanks everyone for testing and helping find the cause of this bug. I will push this out to linux-next shortly. fs/notify/fanotify/fanotify_user.c | 17 +++++++++++------ fs/notify/inotify/inotify_user.c | 17 +++++++++++------ kernel/ucount.c | 19 +++++++++++-------- 3 files changed, 33 insertions(+), 20 deletions(-) diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 64864fb40b40..28b67cb9458d 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -54,22 +54,27 @@ static int fanotify_max_queued_events __read_mostly; #include <linux/sysctl.h> +static long ft_zero = 0; +static long ft_int_max = INT_MAX; + struct ctl_table fanotify_table[] = { { .procname = "max_user_groups", .data = &init_user_ns.ucount_max[UCOUNT_FANOTIFY_GROUPS], - .maxlen = sizeof(int), + .maxlen = sizeof(long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, + .proc_handler = proc_doulongvec_minmax, + .extra1 = &ft_zero, + .extra2 = &ft_int_max, }, { .procname = "max_user_marks", .data = &init_user_ns.ucount_max[UCOUNT_FANOTIFY_MARKS], - .maxlen = sizeof(int), + .maxlen = sizeof(long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, + .proc_handler = proc_doulongvec_minmax, + .extra1 = &ft_zero, + .extra2 = &ft_int_max, }, { .procname = "max_queued_events", diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index 98f61b31745a..62051247f6d2 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -55,22 +55,27 @@ struct kmem_cache *inotify_inode_mark_cachep __read_mostly; #include <linux/sysctl.h> +static long it_zero = 0; +static long it_int_max = INT_MAX; + struct ctl_table inotify_table[] = { { .procname = "max_user_instances", .data = &init_user_ns.ucount_max[UCOUNT_INOTIFY_INSTANCES], - .maxlen = sizeof(int), + .maxlen = sizeof(long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, + .proc_handler = proc_doulongvec_minmax, + .extra1 = &it_zero, + .extra2 = &it_int_max, }, { .procname = "max_user_watches", .data = &init_user_ns.ucount_max[UCOUNT_INOTIFY_WATCHES], - .maxlen = sizeof(int), + .maxlen = sizeof(long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, + .proc_handler = proc_doulongvec_minmax, + .extra1 = &it_zero, + .extra2 = &it_int_max, }, { .procname = "max_queued_events", diff --git a/kernel/ucount.c b/kernel/ucount.c index 77be3bbe3cc4..bb51849e6375 100644 --- a/kernel/ucount.c +++ b/kernel/ucount.c @@ -58,14 +58,17 @@ static struct ctl_table_root set_root = { .permissions = set_permissions, }; -#define UCOUNT_ENTRY(name) \ - { \ - .procname = name, \ - .maxlen = sizeof(int), \ - .mode = 0644, \ - .proc_handler = proc_dointvec_minmax, \ - .extra1 = SYSCTL_ZERO, \ - .extra2 = SYSCTL_INT_MAX, \ +static long ue_zero = 0; +static long ue_int_max = INT_MAX; + +#define UCOUNT_ENTRY(name) \ + { \ + .procname = name, \ + .maxlen = sizeof(long), \ + .mode = 0644, \ + .proc_handler = proc_doulongvec_minmax, \ + .extra1 = &ue_zero, \ + .extra2 = &ue_int_max, \ } static struct ctl_table user_table[] = { UCOUNT_ENTRY("max_user_namespaces"), -- 2.20.1