From 87b7689f7727a542c5afa22bdebd3781dd650a2f Mon Sep 17 00:00:00 2001
From: Csaba Henk <csaba@redhat.com>
Date: Fri, 17 Jul 2020 11:33:36 +0200
Subject: [PATCH 508/511] fuse: fetch arbitrary number of groups from
/proc/[pid]/status
Glusterfs so far constrained itself with an arbitrary limit (32)
for the number of groups read from /proc/[pid]/status (this was
the number of groups shown there prior to Linux commit
v3.7-9553-g8d238027b87e (v3.8-rc1~74^2~59); since this commit, all
groups are shown).
With this change we'll read groups up to the number Glusterfs
supports in general (64k).
Note: the actual number of groups that are made use of in a
regular Glusterfs setup shall still be capped at ~93 due to limitations
of the RPC transport. To be able to handle more groups than that,
brick side gid resolution (server.manage-gids option) can be used along
with NIS, LDAP or other such networked directory service (see
https://github.com/gluster/glusterdocs/blob/5ba15a2/docs/Administrator%20Guide/Handling-of-users-with-many-groups.md#limit-in-the-glusterfs-protocol
).
Also adding some diagnostic messages to frame_fill_groups().
Upstream:
> Reviewed-on: https://review.gluster.org/c/glusterfs/+/24721
> Change-Id: I271f3dc3e6d3c44d6d989c7a2073ea5f16c26ee0
> fixes: #1075
> Signed-off-by: Csaba Henk <csaba@redhat.com>
BUG: 1749304
Change-Id: I80bf99d34087fb95768bf2259d8c4774d9f5d0c5
Signed-off-by: Csaba Henk <csaba@redhat.com>
Reviewed-on: https://code.engineering.redhat.com/gerrit/220920
Tested-by: RHGS Build Bot <nigelb@redhat.com>
Reviewed-by: Sunil Kumar Heggodu Gopala Acharya <sheggodu@redhat.com>
---
libglusterfs/src/glusterfs/stack.h | 7 ++++
tests/bugs/fuse/many-groups-for-acl.t | 13 ++++++-
xlators/mount/fuse/src/fuse-helpers.c | 71 +++++++++++++++++++++++------------
3 files changed, 65 insertions(+), 26 deletions(-)
diff --git a/libglusterfs/src/glusterfs/stack.h b/libglusterfs/src/glusterfs/stack.h
index 1758550..bd466d8 100644
--- a/libglusterfs/src/glusterfs/stack.h
+++ b/libglusterfs/src/glusterfs/stack.h
@@ -429,6 +429,7 @@ call_stack_alloc_groups(call_stack_t *stack, int ngrps)
if (ngrps <= SMALL_GROUP_COUNT) {
stack->groups = stack->groups_small;
} else {
+ GF_FREE(stack->groups_large);
stack->groups_large = GF_CALLOC(ngrps, sizeof(gid_t),
gf_common_mt_groups_t);
if (!stack->groups_large)
@@ -442,6 +443,12 @@ call_stack_alloc_groups(call_stack_t *stack, int ngrps)
}
static inline int
+call_stack_groups_capacity(call_stack_t *stack)
+{
+ return max(stack->ngrps, SMALL_GROUP_COUNT);
+}
+
+static inline int
call_frames_count(call_stack_t *call_stack)
{
call_frame_t *pos;
diff --git a/tests/bugs/fuse/many-groups-for-acl.t b/tests/bugs/fuse/many-groups-for-acl.t
index d959f75..a51b1bc 100755
--- a/tests/bugs/fuse/many-groups-for-acl.t
+++ b/tests/bugs/fuse/many-groups-for-acl.t
@@ -38,6 +38,13 @@ do
done
TEST useradd -o -M -u ${NEW_UID} -g ${NEW_GID} -G ${NEW_USER}-${NEW_GIDS} ${NEW_USER}
+# Linux < 3.8 exports only first 32 gids of pid to userspace
+kernel_exports_few_gids=0
+if [ "$OSTYPE" = Linux ] && \
+ su -m ${NEW_USER} -c "grep ^Groups: /proc/self/status | wc -w | xargs -I@ expr @ - 1 '<' $LAST_GID - $NEW_GID + 1" > /dev/null; then
+ kernel_exports_few_gids=1
+fi
+
# preparation done, start the tests
TEST glusterd
@@ -48,6 +55,8 @@ TEST $CLI volume set $V0 nfs.disable off
TEST $CLI volume set ${V0} server.manage-gids off
TEST $CLI volume start ${V0}
+# This is just a synchronization hack to make sure the bricks are
+# up before going on.
EXPECT_WITHIN ${NFS_EXPORT_TIMEOUT} "1" is_nfs_export_available
# mount the volume with POSIX ACL support, without --resolve-gids
@@ -69,8 +78,8 @@ TEST [ $? -eq 0 ]
su -m ${NEW_USER} -c "touch ${M0}/first-32-gids-2/success > /dev/null"
TEST [ $? -eq 0 ]
-su -m ${NEW_USER} -c "touch ${M0}/gid-64/failure > /dev/null"
-TEST [ $? -ne 0 ]
+su -m ${NEW_USER} -c "touch ${M0}/gid-64/success--if-all-gids-exported > /dev/null"
+TEST [ $? -eq $kernel_exports_few_gids ]
su -m ${NEW_USER} -c "touch ${M0}/gid-120/failure > /dev/null"
TEST [ $? -ne 0 ]
diff --git a/xlators/mount/fuse/src/fuse-helpers.c b/xlators/mount/fuse/src/fuse-helpers.c
index 5bfc40c..6e04cd4 100644
--- a/xlators/mount/fuse/src/fuse-helpers.c
+++ b/xlators/mount/fuse/src/fuse-helpers.c
@@ -139,8 +139,6 @@ get_fuse_state(xlator_t *this, fuse_in_header_t *finh)
return state;
}
-#define FUSE_MAX_AUX_GROUPS \
- 32 /* We can get only up to 32 aux groups from /proc */
void
frame_fill_groups(call_frame_t *frame)
{
@@ -150,8 +148,6 @@ frame_fill_groups(call_frame_t *frame)
char filename[32];
char line[4096];
char *ptr = NULL;
- FILE *fp = NULL;
- int idx = 0;
long int id = 0;
char *saveptr = NULL;
char *endptr = NULL;
@@ -191,45 +187,72 @@ frame_fill_groups(call_frame_t *frame)
call_stack_set_groups(frame->root, ngroups, &mygroups);
} else {
+ FILE *fp = NULL;
+
ret = snprintf(filename, sizeof filename, "/proc/%d/status",
frame->root->pid);
- if (ret >= sizeof filename)
+ if (ret >= sizeof filename) {
+ gf_log(this->name, GF_LOG_ERROR, "procfs path exceeds buffer size");
goto out;
+ }
fp = fopen(filename, "r");
- if (!fp)
+ if (!fp) {
+ gf_log(this->name, GF_LOG_ERROR, "failed to open %s: %s", filename,
+ strerror(errno));
goto out;
+ }
- if (call_stack_alloc_groups(frame->root, ngroups) != 0)
- goto out;
+ for (;;) {
+ gf_boolean_t found_groups = _gf_false;
+ int idx = 0;
- while ((ptr = fgets(line, sizeof line, fp))) {
- if (strncmp(ptr, "Groups:", 7) != 0)
- continue;
+ if (call_stack_alloc_groups(frame->root, ngroups) != 0) {
+ gf_log(this->name, GF_LOG_ERROR,
+ "failed to allocate gid buffer");
+ goto out;
+ }
+ while ((ptr = fgets(line, sizeof line, fp))) {
+ if (strncmp(ptr, "Groups:", 7) == 0) {
+ found_groups = _gf_true;
+ break;
+ }
+ }
+ if (!found_groups) {
+ gf_log(this->name, GF_LOG_ERROR, "cannot find gid list in %s",
+ filename);
+ break;
+ }
ptr = line + 8;
for (ptr = strtok_r(ptr, " \t\r\n", &saveptr); ptr;
ptr = strtok_r(NULL, " \t\r\n", &saveptr)) {
errno = 0;
id = strtol(ptr, &endptr, 0);
- if (errno == ERANGE)
- break;
- if (!endptr || *endptr)
+ if (errno == ERANGE || !endptr || *endptr) {
+ gf_log(this->name, GF_LOG_ERROR, "failed to parse %s",
+ filename);
break;
- frame->root->groups[idx++] = id;
- if (idx == FUSE_MAX_AUX_GROUPS)
+ }
+ if (idx < call_stack_groups_capacity(frame->root))
+ frame->root->groups[idx] = id;
+ idx++;
+ if (idx == GF_MAX_AUX_GROUPS)
break;
}
-
- frame->root->ngrps = idx;
- break;
+ if (idx > call_stack_groups_capacity(frame->root)) {
+ ngroups = idx;
+ rewind(fp);
+ } else {
+ frame->root->ngrps = idx;
+ break;
+ }
}
+ out:
+ if (fp)
+ fclose(fp);
}
-
-out:
- if (fp)
- fclose(fp);
#elif defined(GF_SOLARIS_HOST_OS)
char filename[32];
char scratch[128];
@@ -245,7 +268,7 @@ out:
fp = fopen(filename, "r");
if (fp != NULL) {
if (fgets(scratch, sizeof scratch, fp) != NULL) {
- ngrps = MIN(prcred->pr_ngroups, FUSE_MAX_AUX_GROUPS);
+ ngrps = MIN(prcred->pr_ngroups, GF_MAX_AUX_GROUPS);
if (call_stack_alloc_groups(frame->root, ngrps) != 0) {
fclose(fp);
return;
--
1.8.3.1