Fix CVE-2021-3996: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3996 https://seclists.org/oss-sec/2022/q1/66 Patch copied from upstream source repository: https://github.com/util-linux/util-linux/commit/018a10907fa9885093f6d87401556932c2d8bd2b From 018a10907fa9885093f6d87401556932c2d8bd2b Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Tue, 4 Jan 2022 10:54:20 +0100 Subject: [PATCH] libmount: fix (deleted) suffix issue [CVE-2021-3996] This issue is related to parsing the /proc/self/mountinfo file allows an unprivileged user to unmount other user's filesystems that are either world-writable themselves or mounted in a world-writable directory. The support for "(deleted)" is no more necessary as the Linux kernel does not use it in /proc/self/mountinfo and /proc/self/mount files anymore. Signed-off-by: Karel Zak --- libmount/src/tab_parse.c | 5 ----- tests/expected/findmnt/filter-options | 1 - tests/expected/findmnt/filter-options-nameval-neg | 3 +-- tests/expected/findmnt/filter-types-neg | 1 - tests/expected/findmnt/outputs-default | 3 +-- tests/expected/findmnt/outputs-force-tree | 3 +-- tests/expected/findmnt/outputs-kernel | 3 +-- tests/expected/libmount/tabdiff-mount | 1 - tests/expected/libmount/tabdiff-move | 1 - tests/expected/libmount/tabdiff-remount | 1 - tests/expected/libmount/tabdiff-umount | 1 - tests/expected/libmount/tabfiles-parse-mountinfo | 11 ----------- tests/expected/libmount/tabfiles-py-parse-mountinfo | 11 ----------- tests/ts/findmnt/files/mountinfo | 1 - tests/ts/findmnt/files/mountinfo-nonroot | 1 - tests/ts/libmount/files/mountinfo | 1 - 16 files changed, 4 insertions(+), 44 deletions(-) diff --git a/libmount/src/tab_parse.c b/libmount/src/tab_parse.c index 917779ab6..4407f9c9c 100644 --- a/libmount/src/tab_parse.c +++ b/libmount/src/tab_parse.c @@ -227,11 +227,6 @@ static int mnt_parse_mountinfo_line(struct libmnt_fs *fs, const char *s) goto fail; } - /* remove "\040(deleted)" suffix */ - p = (char *) endswith(fs->target, PATH_DELETED_SUFFIX); - if (p && *p) - *p = '\0'; - s = skip_separator(s); /* (6) vfs options (fs-independent) */ diff --git a/tests/expected/findmnt/filter-options b/tests/expected/findmnt/filter-options index 2606bce76..97b0ead0a 100644 --- a/tests/expected/findmnt/filter-options +++ b/tests/expected/findmnt/filter-options @@ -28,5 +28,4 @@ TARGET SOURCE FSTYPE OPTIONS /home/kzak/.gvfs gvfs-fuse-daemon fuse.gvfs-fuse-daemon rw,nosuid,nodev,relatime,user_id=500,group_id=500 /var/lib/nfs/rpc_pipefs sunrpc rpc_pipefs rw,relatime /mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -/mnt/foo /fooooo bar rw,relatime rc=0 diff --git a/tests/expected/findmnt/filter-options-nameval-neg b/tests/expected/findmnt/filter-options-nameval-neg index 5471d65af..f0467ef75 100644 --- a/tests/expected/findmnt/filter-options-nameval-neg +++ b/tests/expected/findmnt/filter-options-nameval-neg @@ -29,6 +29,5 @@ TARGET SOURCE FSTYPE OPTIO |-/home/kzak /dev/mapper/kzak-home ext4 rw,noatime,barrier=1,data=ordered | `-/home/kzak/.gvfs gvfs-fuse-daemon fuse.gvfs-fuse-daemon rw,nosuid,nodev,relatime,user_id=500,group_id=500 |-/var/lib/nfs/rpc_pipefs sunrpc rpc_pipefs rw,relatime -|-/mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -`-/mnt/foo /fooooo bar rw,relatime +`-/mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 rc=0 diff --git a/tests/expected/findmnt/filter-types-neg b/tests/expected/findmnt/filter-types-neg index 2606bce76..97b0ead0a 100644 --- a/tests/expected/findmnt/filter-types-neg +++ b/tests/expected/findmnt/filter-types-neg @@ -28,5 +28,4 @@ TARGET SOURCE FSTYPE OPTIONS /home/kzak/.gvfs gvfs-fuse-daemon fuse.gvfs-fuse-daemon rw,nosuid,nodev,relatime,user_id=500,group_id=500 /var/lib/nfs/rpc_pipefs sunrpc rpc_pipefs rw,relatime /mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -/mnt/foo /fooooo bar rw,relatime rc=0 diff --git a/tests/expected/findmnt/outputs-default b/tests/expected/findmnt/outputs-default index 59495797b..01599355e 100644 --- a/tests/expected/findmnt/outputs-default +++ b/tests/expected/findmnt/outputs-default @@ -30,6 +30,5 @@ TARGET SOURCE FSTYPE OPTIO |-/home/kzak /dev/mapper/kzak-home ext4 rw,noatime,barrier=1,data=ordered | `-/home/kzak/.gvfs gvfs-fuse-daemon fuse.gvfs-fuse-daemon rw,nosuid,nodev,relatime,user_id=500,group_id=500 |-/var/lib/nfs/rpc_pipefs sunrpc rpc_pipefs rw,relatime -|-/mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -`-/mnt/foo /fooooo bar rw,relatime +`-/mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 rc=0 diff --git a/tests/expected/findmnt/outputs-force-tree b/tests/expected/findmnt/outputs-force-tree index 59495797b..01599355e 100644 --- a/tests/expected/findmnt/outputs-force-tree +++ b/tests/expected/findmnt/outputs-force-tree @@ -30,6 +30,5 @@ TARGET SOURCE FSTYPE OPTIO |-/home/kzak /dev/mapper/kzak-home ext4 rw,noatime,barrier=1,data=ordered | `-/home/kzak/.gvfs gvfs-fuse-daemon fuse.gvfs-fuse-daemon rw,nosuid,nodev,relatime,user_id=500,group_id=500 |-/var/lib/nfs/rpc_pipefs sunrpc rpc_pipefs rw,relatime -|-/mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -`-/mnt/foo /fooooo bar rw,relatime +`-/mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 rc=0 diff --git a/tests/expected/findmnt/outputs-kernel b/tests/expected/findmnt/outputs-kernel index 59495797b..01599355e 100644 --- a/tests/expected/findmnt/outputs-kernel +++ b/tests/expected/findmnt/outputs-kernel @@ -30,6 +30,5 @@ TARGET SOURCE FSTYPE OPTIO |-/home/kzak /dev/mapper/kzak-home ext4 rw,noatime,barrier=1,data=ordered | `-/home/kzak/.gvfs gvfs-fuse-daemon fuse.gvfs-fuse-daemon rw,nosuid,nodev,relatime,user_id=500,group_id=500 |-/var/lib/nfs/rpc_pipefs sunrpc rpc_pipefs rw,relatime -|-/mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -`-/mnt/foo /fooooo bar rw,relatime +`-/mnt/sounds //foo.home/bar/ cifs rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 rc=0 diff --git a/tests/expected/libmount/tabdiff-mount b/tests/expected/libmount/tabdiff-mount index 420aeacd5..3c18f8dc4 100644 --- a/tests/expected/libmount/tabdiff-mount +++ b/tests/expected/libmount/tabdiff-mount @@ -1,3 +1,2 @@ /dev/mapper/kzak-home on /home/kzak: MOUNTED -/fooooo on /mnt/foo: MOUNTED tmpfs on /mnt/test/foo bar: MOUNTED diff --git a/tests/expected/libmount/tabdiff-move b/tests/expected/libmount/tabdiff-move index 24f9bc791..95820d93e 100644 --- a/tests/expected/libmount/tabdiff-move +++ b/tests/expected/libmount/tabdiff-move @@ -1,3 +1,2 @@ //foo.home/bar/ on /mnt/music: MOVED to /mnt/music -/fooooo on /mnt/foo: UMOUNTED tmpfs on /mnt/test/foo bar: UMOUNTED diff --git a/tests/expected/libmount/tabdiff-remount b/tests/expected/libmount/tabdiff-remount index 82ebeab39..876bfd953 100644 --- a/tests/expected/libmount/tabdiff-remount +++ b/tests/expected/libmount/tabdiff-remount @@ -1,4 +1,3 @@ /dev/mapper/kzak-home on /home/kzak: REMOUNTED from 'rw,noatime,barrier=1,data=ordered' to 'ro,noatime,barrier=1,data=ordered' //foo.home/bar/ on /mnt/sounds: REMOUNTED from 'rw,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344' to 'ro,relatime,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344' -/fooooo on /mnt/foo: UMOUNTED tmpfs on /mnt/test/foo bar: UMOUNTED diff --git a/tests/expected/libmount/tabdiff-umount b/tests/expected/libmount/tabdiff-umount index a3e0fe48a..c7be725b9 100644 --- a/tests/expected/libmount/tabdiff-umount +++ b/tests/expected/libmount/tabdiff-umount @@ -1,3 +1,2 @@ /dev/mapper/kzak-home on /home/kzak: UMOUNTED -/fooooo on /mnt/foo: UMOUNTED tmpfs on /mnt/test/foo bar: UMOUNTED diff --git a/tests/expected/libmount/tabfiles-parse-mountinfo b/tests/expected/libmount/tabfiles-parse-mountinfo index 47eb77006..d5ba5248e 100644 --- a/tests/expected/libmount/tabfiles-parse-mountinfo +++ b/tests/expected/libmount/tabfiles-parse-mountinfo @@ -351,17 +351,6 @@ id: 47 parent: 20 devno: 0:38 ------ fs: -source: /fooooo -target: /mnt/foo -fstype: bar -optstr: rw,relatime -VFS-optstr: rw,relatime -FS-opstr: rw -root: / -id: 48 -parent: 20 -devno: 0:39 ------- fs: source: tmpfs target: /mnt/test/foo bar fstype: tmpfs diff --git a/tests/expected/libmount/tabfiles-py-parse-mountinfo b/tests/expected/libmount/tabfiles-py-parse-mountinfo index 47eb77006..d5ba5248e 100644 --- a/tests/expected/libmount/tabfiles-py-parse-mountinfo +++ b/tests/expected/libmount/tabfiles-py-parse-mountinfo @@ -351,17 +351,6 @@ id: 47 parent: 20 devno: 0:38 ------ fs: -source: /fooooo -target: /mnt/foo -fstype: bar -optstr: rw,relatime -VFS-optstr: rw,relatime -FS-opstr: rw -root: / -id: 48 -parent: 20 -devno: 0:39 ------- fs: source: tmpfs target: /mnt/test/foo bar fstype: tmpfs diff --git a/tests/ts/findmnt/files/mountinfo b/tests/ts/findmnt/files/mountinfo index 475ea1a33..ff1e664a8 100644 --- a/tests/ts/findmnt/files/mountinfo +++ b/tests/ts/findmnt/files/mountinfo @@ -30,4 +30,3 @@ 44 41 0:36 / /home/kzak/.gvfs rw,nosuid,nodev,relatime - fuse.gvfs-fuse-daemon gvfs-fuse-daemon rw,user_id=500,group_id=500 45 20 0:37 / /var/lib/nfs/rpc_pipefs rw,relatime - rpc_pipefs sunrpc rw 47 20 0:38 / /mnt/sounds rw,relatime - cifs //foo.home/bar/ rw,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -48 20 0:39 / /mnt/foo\040(deleted) rw,relatime - bar /fooooo rw diff --git a/tests/ts/findmnt/files/mountinfo-nonroot b/tests/ts/findmnt/files/mountinfo-nonroot index e15b46701..87b421d2e 100644 --- a/tests/ts/findmnt/files/mountinfo-nonroot +++ b/tests/ts/findmnt/files/mountinfo-nonroot @@ -29,4 +29,3 @@ 44 41 0:36 / /home/kzak/.gvfs rw,nosuid,nodev,relatime - fuse.gvfs-fuse-daemon gvfs-fuse-daemon rw,user_id=500,group_id=500 45 20 0:37 / /var/lib/nfs/rpc_pipefs rw,relatime - rpc_pipefs sunrpc rw 47 20 0:38 / /mnt/sounds rw,relatime - cifs //foo.home/bar/ rw,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -48 20 0:39 / /mnt/foo\040(deleted) rw,relatime - bar /fooooo rw diff --git a/tests/ts/libmount/files/mountinfo b/tests/ts/libmount/files/mountinfo index c06307183..2b0174048 100644 --- a/tests/ts/libmount/files/mountinfo +++ b/tests/ts/libmount/files/mountinfo @@ -30,5 +30,4 @@ 44 41 0:36 / /home/kzak/.gvfs rw,nosuid,nodev,relatime - fuse.gvfs-fuse-daemon gvfs-fuse-daemon rw,user_id=500,group_id=500 45 20 0:37 / /var/lib/nfs/rpc_pipefs rw,relatime - rpc_pipefs sunrpc rw 47 20 0:38 / /mnt/sounds rw,relatime - cifs //foo.home/bar/ rw,unc=\\foo.home\bar,username=kzak,domain=SRGROUP,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.111.1,posixpaths,serverino,acl,rsize=16384,wsize=57344 -48 20 0:39 / /mnt/foo\040(deleted) rw,relatime - bar /fooooo rw 49 20 0:56 / /mnt/test/foo bar rw,relatime shared:323 - tmpfs tmpfs rw -- 2.34.0