--- /dev/null
+From 07d209bd092d023976fdb881ba6d4b30fe18aebe Mon Sep 17 00:00:00 2001
+From: Jan Kara <jack@suse.cz>
+Date: Thu, 4 Sep 2014 14:06:55 +0200
+Subject: [PATCH] udf: Avoid infinite loop when processing indirect ICBs
+
+commit c03aa9f6e1f938618e6db2e23afef0574efeeb65 upstream.
+
+We did not implement any bound on number of indirect ICBs we follow when
+loading inode. Thus corrupted medium could cause kernel to go into an
+infinite loop, possibly causing a stack overflow.
+
+Fix the possible stack overflow by removing recursion from
+__udf_read_inode() and limit number of indirect ICBs we follow to avoid
+infinite loops.
+
+Upstream-Status: Backport
+
+Signed-off-by: Jan Kara <jack@suse.cz>
+Cc: Chuck Ebbert <cebbert.lkml@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
+---
+ fs/udf/inode.c | 35 +++++++++++++++++++++--------------
+ 1 file changed, 21 insertions(+), 14 deletions(-)
+
+diff --git a/fs/udf/inode.c b/fs/udf/inode.c
+index b6d15d3..aa02328 100644
+--- a/fs/udf/inode.c
++++ b/fs/udf/inode.c
+@@ -1270,13 +1270,22 @@ update_time:
+ return 0;
+ }
+
++/*
++ * Maximum length of linked list formed by ICB hierarchy. The chosen number is
++ * arbitrary - just that we hopefully don't limit any real use of rewritten
++ * inode on write-once media but avoid looping for too long on corrupted media.
++ */
++#define UDF_MAX_ICB_NESTING 1024
++
+ static void __udf_read_inode(struct inode *inode)
+ {
+ struct buffer_head *bh = NULL;
+ struct fileEntry *fe;
+ uint16_t ident;
+ struct udf_inode_info *iinfo = UDF_I(inode);
++ unsigned int indirections = 0;
+
++reread:
+ /*
+ * Set defaults, but the inode is still incomplete!
+ * Note: get_new_inode() sets the following on a new inode:
+@@ -1313,28 +1322,26 @@ static void __udf_read_inode(struct inode *inode)
+ ibh = udf_read_ptagged(inode->i_sb, &iinfo->i_location, 1,
+ &ident);
+ if (ident == TAG_IDENT_IE && ibh) {
+- struct buffer_head *nbh = NULL;
+ struct kernel_lb_addr loc;
+ struct indirectEntry *ie;
+
+ ie = (struct indirectEntry *)ibh->b_data;
+ loc = lelb_to_cpu(ie->indirectICB.extLocation);
+
+- if (ie->indirectICB.extLength &&
+- (nbh = udf_read_ptagged(inode->i_sb, &loc, 0,
+- &ident))) {
+- if (ident == TAG_IDENT_FE ||
+- ident == TAG_IDENT_EFE) {
+- memcpy(&iinfo->i_location,
+- &loc,
+- sizeof(struct kernel_lb_addr));
+- brelse(bh);
+- brelse(ibh);
+- brelse(nbh);
+- __udf_read_inode(inode);
++ if (ie->indirectICB.extLength) {
++ brelse(bh);
++ brelse(ibh);
++ memcpy(&iinfo->i_location, &loc,
++ sizeof(struct kernel_lb_addr));
++ if (++indirections > UDF_MAX_ICB_NESTING) {
++ udf_err(inode->i_sb,
++ "too many ICBs in ICB hierarchy"
++ " (max %d supported)\n",
++ UDF_MAX_ICB_NESTING);
++ make_bad_inode(inode);
+ return;
+ }
+- brelse(nbh);
++ goto reread;
+ }
+ }
+ brelse(ibh);
+--
+1.9.1
+
