busybox: don't clobber dangling symlinks
PATCH 1/1 busybox: don't clobber dangling symlinks
We sometimes create dangling symlinks in the target directory. That is because we need canonical targets, as relative targets don't work well with BR2_ROOTFS_MERGED_USR. For example, the vim package installs the /bin/vi symlink to /usr/bin/vim. This symlink might be dangling when the build host has no vim installed there.
Patch the busybox install.sh script to avoid clobber of dangling symlinks.
Fixes:
http://autobuild.buildroot.net/results/796/796107430db6545401d9926e84f19eaf2040b756/
--- ...l.sh-don-t-clobber-dangling-symlinks.patch | 38 +++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 package/busybox/0003-install.sh-don-t-clobber-dangling-symlinks.patch
package/busybox/0003-install.sh-don-t-clobber-dangling-symlinks.patch new file +38 -0
@@ -0,0 +1,38 @@ +From c9f1a877f1b9e2602913600d769edb17ee41d15d Mon Sep 17 00:00:00 2001 +From: Baruch Siach <[email protected]> +Date: Tue, 17 Jul 2018 13:18:09 +0300 +Subject: [PATCH] install.sh: don't clobber dangling symlinks + +Symlinks in a subdirectory that is to become target rootfs are sometimes +dangling because they link to canonical file names that are not present +on the host, but are present relative to the target rootfs root. Don't +copy over dangling symlinks when noclobber is enabled + +The -e test treats dangling symlinks as non-existent files. Add -h test +that returns true for all symlinks. + +Cc: Yann E. MORIN <[email protected]> +Signed-off-by: Baruch Siach <[email protected]> +--- +Upstream status: +http://lists.busybox.net/pipermail/busybox/2018-July/086555.html + + applets/install.sh | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/applets/install.sh b/applets/install.sh +index 9aede0f530e2..415896893e86 100755 +--- a/applets/install.sh ++++ b/applets/install.sh +@@ -83,7 +83,7 @@ install -m 755 busybox "$prefix/bin/busybox" || exit 1 + for i in $h; do + appdir=`dirname "$i"` + app=`basename "$i"` +- if [ x"$noclobber" = x"1" ] && [ -e "$prefix/$i" ]; then ++ if [ x"$noclobber" = x"1" ] && ([ -e "$prefix/$i" ] || [ -h "$prefix/$i" ]); then + echo " $prefix/$i already exists" + continue + fi +-- +2.18.0 +
Signature · 1 line
2.18.0
PATCH 1/1 busybox: don't clobber dangling symlinks
Quoted 77 lines
From: "Baruch Siach" <[email protected]>
To: "buildroot" <[email protected]>
Cc: "Baruch Siach" <[email protected]>, "ratbert90" <[email protected]>, "DATACOM" <[email protected]>, "Yann Morin" <[email protected]>
Sent: Tuesday, July 17, 2018 8:01:43 AM
Subject: [PATCH] busybox: don't clobber dangling symlinksWe sometimes create dangling symlinks in the target directory. That is because we need canonical targets, as relative targets don't work well with
BR2_ROOTFS_MERGED_USR. For example, the vim package installs the/bin/visymlink to/usr/bin/vim. This symlink might be dangling when the build host has no vim installed there.Patch the busybox
install.shscript to avoid clobber of dangling symlinks.Fixes:
http://autobuild.buildroot.net/results/796/796107430db6545401d9926e84f19eaf2040b756/Cc Adam Duskett <[email protected]>Cc Carlos Santos <[email protected]>Cc Yann E. MORIN <[email protected]>Signed-off-by Baruch Siach <[email protected]>---
...l.sh-don-t-clobber-dangling-symlinks.patch | 38 +++++++++++++++++++1 file changed, 38 insertions(+)create mode 100644
package/busybox/0003-install.sh-don-t-clobber-dangling-symlinks.patchdiff --git
a/package/busybox/0003-install.sh-don-t-clobber-dangling-symlinks.patchb/package/busybox/0003-install.sh-don-t-clobber-dangling-symlinks.patchnew file mode 100644
index 000000000000..b6fb5b92368fpackage/busybox/0003-install.sh-don-t-clobber-dangling-symlinks.patch new file +32
-0@@ -0,0 +1,38 @@ +From c9f1a877f1b9e2602913600d769edb17ee41d15d Mon Sep 17 00:00:00 2001 +From: Baruch Siach <[email protected]> +Date: Tue, 17 Jul 2018 13:18:09 +0300 +Subject: [PATCH] install.sh: don't clobber dangling symlinks + +Symlinks in a subdirectory that is to become target rootfs are sometimes +dangling because they link to canonical file names that are not present +on the host, but are present relative to the target rootfs root. Don't +copy over dangling symlinks when noclobber is enabled + +The -e test treats dangling symlinks as non-existent files. Add -h test +that returns true for all symlinks. + +Cc: Yann E. MORIN <[email protected]> +Signed-off-by: Baruch Siach <[email protected]> +--- +Upstream status: +http://lists.busybox.net/pipermail/busybox/2018-July/086555.html + + applets/install.sh | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/applets/install.sh b/applets/install.sh +index 9aede0f530e2..415896893e86 100755 +--- a/applets/install.sh ++++ b/applets/install.sh +@@ -83,7 +83,7 @@ install -m 755 busybox "$prefix/bin/busybox" || exit 1 + for i in $h; do + appdir=`dirname "$i"` + app=`basename "$i"` +- if [ x"$noclobber" = x"1" ] && [ -e "$prefix/$i" ]; then ++ if [ x"$noclobber" = x"1" ] && ([ -e "$prefix/$i" ] || [ -h "$prefix/$i" ]);then
package/busybox/0003-install.sh-don-t-clobber-dangling-symlinks.patch new file +6
-1+ echo " $prefix/$i already exists" + continue + fi +-- +2.18.0 + --
Quoted 1 line
2.18.0
I'm not sure if this is a good approach. Perhaps we should look for dangling symlinks in target-finalize and stop if one is found.
For the specific case of vim, I propose a different solution:
https://patchwork.ozlabs.org/patch/945700/
Signature · 3 lines
Carlos Santos (Casantos) - DATACOM, P&D ?Marched towards the enemy, spear upright, armed with the certainty that only the ignorant can have.? ? Epitaph of a volunteer
Thomas Petazzoni
AppliedPATCH 1/1 busybox: don't clobber dangling symlinks
In reply to Baruch SiachHello,
Quoted 12 lines · Baruch Siach
We sometimes create dangling symlinks in the target directory. That is because we need canonical targets, as relative targets don't work well with
BR2_ROOTFS_MERGED_USR. For example, the vim package installs the/bin/visymlink to/usr/bin/vim. This symlink might be dangling when the build host has no vim installed there.Patch the busybox
install.shscript to avoid clobber of dangling symlinks.Fixes:
http://autobuild.buildroot.net/results/796/796107430db6545401d9926e84f19eaf2040b756/
Quoted 8 lines
Cc Adam Duskett <[email protected]>Cc Carlos Santos <[email protected]>Cc Yann E. MORIN <[email protected]>Signed-off-by Baruch Siach <[email protected]>--- ...l.sh-don-t-clobber-dangling-symlinks.patch | 38 +++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 package/busybox/0003-install.sh-don-t-clobber-dangling-symlinks.patch
Applied to master, thanks.
Carlos: I know you disagreed with this patch, but since it has been merged by the upstream Busybox developers, I don't see the point of not merging it in Buildroot as well, since we will anyway get this behavior at the next Busybox version bump.
Best regards,
Thomas
Signature · 3 lines
Thomas Petazzoni, CTO, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering https://bootlin.com