From 5893e64ca8c147b7acfa12cd9824f254d53ee261 Mon Sep 17 00:00:00 2001
From: mohit84 <moagrawa@redhat.com>
Date: Wed, 4 Nov 2020 09:02:03 +0530
Subject: [PATCH 496/511] posix: Use MALLOC instead of alloca to allocate
 memory for xattrs list (#1730)

In case of file is having huge xattrs on backend a brick process is
crashed while alloca(size) limit has been crossed 256k because iot_worker
stack size is 256k.

> Fixes: #1699
> Signed-off-by: Mohit Agrawal <moagrawa@redhat.com>
> Change-Id: I100468234f83329a7d65b43cbe4e10450c1ccecd
> (Cherry pick from commit fd666caa35ac84dd1cba55399761982011b77112)
> (Reviewed on upstream link https://github.com/gluster/glusterfs/pull/1828)

Change-Id: I100468234f83329a7d65b43cbe4e10450c1ccecd
Bug: 1903468
Signed-off-by: Mohit Agrawal <moagrawa@redhat.com>
Reviewed-on: https://code.engineering.redhat.com/gerrit/220872
Tested-by: RHGS Build Bot <nigelb@redhat.com>
Reviewed-by: Sunil Kumar Heggodu Gopala Acharya <sheggodu@redhat.com>
---
 xlators/storage/posix/src/posix-gfid-path.c    |  5 ++++-
 xlators/storage/posix/src/posix-helpers.c      |  3 ++-
 xlators/storage/posix/src/posix-inode-fd-ops.c | 12 +++++++++---
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/xlators/storage/posix/src/posix-gfid-path.c b/xlators/storage/posix/src/posix-gfid-path.c
index 64b5c6c..01315ac 100644
--- a/xlators/storage/posix/src/posix-gfid-path.c
+++ b/xlators/storage/posix/src/posix-gfid-path.c
@@ -195,7 +195,8 @@ posix_get_gfid2path(xlator_t *this, inode_t *inode, const char *real_path,
             if (size == 0)
                 goto done;
         }
-        list = alloca(size);
+
+        list = GF_MALLOC(size, gf_posix_mt_char);
         if (!list) {
             *op_errno = errno;
             goto err;
@@ -309,6 +310,7 @@ done:
             GF_FREE(paths[j]);
     }
     ret = 0;
+    GF_FREE(list);
     return ret;
 err:
     if (path)
@@ -317,5 +319,6 @@ err:
         if (paths[j])
             GF_FREE(paths[j]);
     }
+    GF_FREE(list);
     return ret;
 }
diff --git a/xlators/storage/posix/src/posix-helpers.c b/xlators/storage/posix/src/posix-helpers.c
index 73a44be..ceac52a 100644
--- a/xlators/storage/posix/src/posix-helpers.c
+++ b/xlators/storage/posix/src/posix-helpers.c
@@ -349,7 +349,7 @@ _posix_get_marker_all_contributions(posix_xattr_filler_t *filler)
         goto out;
     }
 
-    list = alloca(size);
+    list = GF_MALLOC(size, gf_posix_mt_char);
     if (!list) {
         goto out;
     }
@@ -379,6 +379,7 @@ _posix_get_marker_all_contributions(posix_xattr_filler_t *filler)
     ret = 0;
 
 out:
+    GF_FREE(list);
     return ret;
 }
 
diff --git a/xlators/storage/posix/src/posix-inode-fd-ops.c b/xlators/storage/posix/src/posix-inode-fd-ops.c
index 21119ea..1d37aed 100644
--- a/xlators/storage/posix/src/posix-inode-fd-ops.c
+++ b/xlators/storage/posix/src/posix-inode-fd-ops.c
@@ -3305,7 +3305,7 @@ posix_get_ancestry_non_directory(xlator_t *this, inode_t *leaf_inode,
         goto out;
     }
 
-    list = alloca(size);
+    list = GF_MALLOC(size, gf_posix_mt_char);
     if (!list) {
         *op_errno = errno;
         goto out;
@@ -3385,6 +3385,7 @@ posix_get_ancestry_non_directory(xlator_t *this, inode_t *leaf_inode,
     op_ret = 0;
 
 out:
+    GF_FREE(list);
     return op_ret;
 }
 
@@ -3810,7 +3811,8 @@ posix_getxattr(call_frame_t *frame, xlator_t *this, loc_t *loc,
         if (size == 0)
             goto done;
     }
-    list = alloca(size);
+
+    list = GF_MALLOC(size, gf_posix_mt_char);
     if (!list) {
         op_errno = errno;
         goto out;
@@ -3937,6 +3939,7 @@ out:
         dict_unref(dict);
     }
 
+    GF_FREE(list);
     return 0;
 }
 
@@ -4136,7 +4139,8 @@ posix_fgetxattr(call_frame_t *frame, xlator_t *this, fd_t *fd, const char *name,
         if (size == 0)
             goto done;
     }
-    list = alloca(size + 1);
+
+    list = GF_MALLOC(size, gf_posix_mt_char);
     if (!list) {
         op_ret = -1;
         op_errno = ENOMEM;
@@ -4240,6 +4244,8 @@ out:
     if (dict)
         dict_unref(dict);
 
+    GF_FREE(list);
+
     return 0;
 }
 
-- 
1.8.3.1