bug#65599: mv and cp give a pointless warning when moving/copying a directory

[Paul Eggert]

On 2023-08-29 11:20, Bruno Haible wrote:

People say that "chown only works for root anyway" [1]


I don't think that is the issue here. fchownat is failing with EACCES, 
which is supposed to mean that search permission is denied on a 
component of the path prefix, but in Android I guess EACCES also means 
the calling process doesn't have the required permissions to change 
ownership (i.e., errno should be EPERM according to POSIX).


Clearly search permission is allowed, since there's a successful 
utimensat call with the same file name. So EACCES does not mean search 
permission is denied; it means something else.


Do fchown, chown, and lchown have similar bugs on Android?

Although the attached hacky coreutils patch (which I haven't installed) 
might solve the immediate problem, it sounds like this is something that 
Gnulib's fchownat (and maybe related modules) should fix on Android, so 
that the fix is everywhere and not just in mv+cp.


diff --git a/src/copy.c b/src/copy.c
index b9fff03a3..7b901ffc3 100644
--- a/src/copy.c
+++ b/src/copy.c
@@ -3460,6 +3460,12 @@ chown_failure_ok (struct cp_options const *x)
  But root probably wants to know, e.g. if NFS disallows it,
  or if the target system doesn't support file ownership.  */
 
+#ifdef __ANDROID__
+  /* Work around Android bug .  */
+  if (errno == EACCES && !x->chown_privileges)
+return true;
+#endif
+
   return ((errno == EPERM || errno == EINVAL) && !x->chown_privileges);
 }
 

bug#65617: coreutils 9.4: seg.fault in readutmp with systemd

[Paul Eggert]

Thanks for reporting that. I installed the attached patch into Gnulib 
and this should appear in the next coreutils release.From 1e6a26f9312bb47e070f94b17b14dc1a6ffbb74f Mon Sep 17 00:00:00 2001
From: Paul Eggert 
Date: Wed, 30 Aug 2023 18:26:52 -0700
Subject: [PATCH] readutmp: fix core dump if --enable-systemd
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Problem reported by Thorsten Kukuk .
* lib/readutmp.c (read_utmp_from_systemd):
Don’t assume session_ptr != NULL if num_sessions == 0.
In practice it can be null, and the man page OKs this behavior.
---
 ChangeLog  | 8 
 lib/readutmp.c | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index d4b2287307..9c9c89638c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2023-08-30  Paul Eggert  
+
+	readutmp: fix core dump if --enable-systemd
+	Problem reported by Thorsten Kukuk .
+	* lib/readutmp.c (read_utmp_from_systemd):
+	Don’t assume session_ptr != NULL if num_sessions == 0.
+	In practice it can be null, and the man page OKs this behavior.
+
 2023-08-30  Bruno Haible  
 
 	doc: Mention the module 'wchar-single'.
diff --git a/lib/readutmp.c b/lib/readutmp.c
index 0173b7e0c1..e99158677c 100644
--- a/lib/readutmp.c
+++ b/lib/readutmp.c
@@ -795,7 +795,7 @@ read_utmp_from_systemd (idx_t *n_entries, STRUCT_UTMP **utmp_buf, int options)
 {
   char **sessions;
   int num_sessions = sd_get_sessions ();
-  if (num_sessions >= 0)
+  if (num_sessions > 0)
 {
   char **session_ptr;
   for (session_ptr = sessions; *session_ptr != NULL; session_ptr++)
-- 
2.39.2

bug#65617: coreutils 9.4: seg.fault in readutmp with systemd

[Thorsten Kukuk via GNU coreutils Bug Reports]

coreutils 9.4 with the --enable-systemd option seg.faults in
lib/readutmp.c, line 801:

for (session_ptr = sessions; *session_ptr != NULL; session_ptr++)

If there is no session, "sessions" is NULL and "*session_ptr" will
dereference a NULL pointer.
Affected are who, pinky and uptime.

A simple fix:

diff --git a/lib/readutmp.c b/lib/readutmp.c
index 0173b7e0c1..e99158677c 100644
--- a/lib/readutmp.c
+++ b/lib/readutmp.c
@@ -795,7 +795,7 @@ read_utmp_from_systemd (idx_t *n_entries, STRUCT_UTMP 
**utmp_buf, int options)
 {
   char **sessions;
   int num_sessions = sd_get_sessions ();
-  if (num_sessions >= 0)
+  if (num_sessions > 0)
 {
   char **session_ptr;
   for (session_ptr = sessions; *session_ptr != NULL; session_ptr++)


-- 
Thorsten Kukuk, Distinguished Engineer, Senior Architect, Future Technologies
SUSE Software Solutions Germany GmbH, Frankenstraße 146, 90461 Nuernberg, 
Germany
Managing Director: Ivo Totev, Andrew McDonald, Werner Knoblich
(HRB 36809, AG Nürnberg)