From: Joey Hess <joeyh@xxxxxxxxxx> Some systems have /etc/mtab symlink to /proc/mounts. In that case mount.nfs complains: Can't set permissions on mtab: Operation not permitted See https://bugs.debian.org/476577 This change makes mount.nfs handle symlinked /etc/mtab the way umount.nfs and util- linux handle it. Cc: Chuck Lever <chuck.lever@xxxxxxxxxx> Signed-off-by: Joey Hess <joeyh@xxxxxxxxxx> [ pvorel: took patch from Debian, rebased for 2.4.3-rc1 and created commit message. Patch is also used in Gentoo. ] Signed-off-by: Petr Vorel <petr.vorel@xxxxxxxxx> --- Hi, if you merge, please keep Joey as the author in git :). Kind regards, Petr utils/mount/fstab.c | 2 +- utils/mount/fstab.h | 1 + utils/mount/mount.c | 7 +++++++ 3 files changed, 9 insertions(+), 1 deletion(-) diff --git a/utils/mount/fstab.c b/utils/mount/fstab.c index 8b0aaf1a..146d8f40 100644 --- a/utils/mount/fstab.c +++ b/utils/mount/fstab.c @@ -61,7 +61,7 @@ mtab_does_not_exist(void) { return var_mtab_does_not_exist; } -static int +int mtab_is_a_symlink(void) { get_mtab_info(); return var_mtab_is_a_symlink; diff --git a/utils/mount/fstab.h b/utils/mount/fstab.h index 313bf9b3..8676c8c2 100644 --- a/utils/mount/fstab.h +++ b/utils/mount/fstab.h @@ -7,6 +7,7 @@ #define _PATH_FSTAB "/etc/fstab" #endif +int mtab_is_a_symlink(void); int mtab_is_writable(void); int mtab_does_not_exist(void); void reset_mtab_info(void); diff --git a/utils/mount/mount.c b/utils/mount/mount.c index 91f10877..92a0dfe4 100644 --- a/utils/mount/mount.c +++ b/utils/mount/mount.c @@ -204,6 +204,13 @@ create_mtab (void) { int flags; mntFILE *mfp; + /* Avoid writing if the mtab is a symlink to /proc/mounts, since + that would create a file /proc/mounts in case the proc filesystem + is not mounted, and the fchmod below would also fail. */ + if (mtab_is_a_symlink()) { + return EX_SUCCESS; + } + lock_mtab(); mfp = nfs_setmntent (MOUNTED, "a+"); -- 2.24.0
