From 681fd2bed8eaba88693867ba928a1c03a5b152cc Mon Sep 17 00:00:00 2001 From: Ganael Laplanche Date: Fri, 21 Jun 2024 10:39:09 -0600 Subject: [PATCH] pax: Terminate loop for empty directory names Pax can sometimes loop forever. For example: $ mkdir -p /tmp/src/foo/bar $ rm -rf /tmp/dst ; mkdir -p /tmp/dst $ cd /tmp/src $ echo 'foo/bar/' | /bin/pax -r -w -d -pe "/tmp/dst" Here, pax(1) infinitely deletes and re-creates /tmp/dst/foo/bar/. The problem is that chk_path() (bin/pax/file_subs.c), called from node_creat() also creates the leaf directory when a trailing '/' appears in the directory name to create. When the execution goes back from chk_path() to node_creat(), the function still cannot create the leaf directory (it has been created by chk_path()), so it unlinks it and calls node_creat() again. The function re-creates it, and so on... In node_creat() detect trailing slashes and not create a leaf directory, but only intermediate ones. PR: 277060 Reviewed by: imp --- bin/pax/file_subs.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/bin/pax/file_subs.c b/bin/pax/file_subs.c index 7214de337ec4..06602c12db2c 100644 --- a/bin/pax/file_subs.c +++ b/bin/pax/file_subs.c @@ -555,7 +555,12 @@ chk_path( char *name, uid_t st_uid, gid_t st_gid) * work forward from the first / and check each part of the path */ spt = strchr(spt, '/'); - if (spt == NULL) + + /* + * skip creating a leaf dir (with an ending '/') as we only want + * to create parents here + */ + if ((spt == NULL) || (*(spt + 1) == '\0')) break; *spt = '\0';