Blame SOURCES/sudo-1.9.5-sesh-bad-condition.patch

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From 613a8053dbc3ab43cf0cdaf09f207ffdb0b40e08 Mon Sep 17 00:00:00 2001
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From: Radovan Sroka <rsroka@redhat.com>
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Date: Wed, 7 Apr 2021 14:43:40 +0200
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Subject: [PATCH] Fixed bad condition for sesh args
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In selinux_edit_copy_tfiles() when there is only one file and the open()
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fails then number of arguments is lower than expected.
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Sudo should return error with or without "Defaults !sudoedit_checkdir" set.
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This was found with regression testing of CVE-2021-23240.
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Signed-off-by: Radovan Sroka <rsroka@redhat.com>
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---
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 src/sudo_edit.c | 10 ++++++++--
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 1 file changed, 8 insertions(+), 2 deletions(-)
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diff --git a/src/sudo_edit.c b/src/sudo_edit.c
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index 41fc61c3a..15c75d8c4 100644
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--- a/src/sudo_edit.c
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+++ b/src/sudo_edit.c
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@@ -529,6 +529,8 @@ selinux_edit_copy_tfiles(struct command_details *command_details,
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     if (nfiles < 1)
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 	debug_return_int(0);
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+    const int check_dir = ISSET(command_details->flags, CD_SUDOEDIT_CHECKDIR);
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+
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     /* Construct common args for sesh */
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     sesh_nargs = 5 + (nfiles * 2) + 1;
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     sesh_args = sesh_ap = reallocarray(NULL, sesh_nargs, sizeof(char *));
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@@ -538,7 +540,7 @@ selinux_edit_copy_tfiles(struct command_details *command_details,
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     }
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     *sesh_ap++ = "sesh";
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     *sesh_ap++ = "-e";
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-    if (ISSET(command_details->flags, CD_SUDOEDIT_CHECKDIR)) {
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+    if (check_dir) {
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 	if ((user_str = selinux_fmt_sudo_user()) == NULL) {
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 	    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
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 	    goto done;
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@@ -581,7 +583,11 @@ selinux_edit_copy_tfiles(struct command_details *command_details,
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     if (tfd != -1)
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 	close(tfd);
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-    if (sesh_ap - sesh_args > 3) {
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+    /*
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+     * check dir adds two more args to the array
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+     */
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+    if ((!check_dir && sesh_ap - sesh_args > 3)
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+        || (check_dir && sesh_ap - sesh_args > 5)) {
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 	/* Run sesh -e 1 <t1> <o1> ... <tn> <on> */
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 	error = selinux_run_helper(command_details->cred.uid, command_details->cred.gid,
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 	    command_details->cred.ngroups, command_details->cred.groups, sesh_args,