kernel/git/stable/linux-stable.git/fs/ext4/acl.c, branch linux-3.16.y

ext4: Don't clear SGID when inheriting ACLs

2017-10-12T14:28:09+00:00

commit a3bb2d5587521eea6dab2d05326abb0afb460abd upstream. When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit set, DIR1 is expected to have SGID bit set (and owning group equal to the owning group of 'DIR0'). However when 'DIR0' also has some default ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on 'DIR1' to get cleared if user is not member of the owning group. Fix the problem by moving posix_acl_update_mode() out of __ext4_set_acl() into ext4_set_acl(). That way the function will not be called when inheriting ACLs which is what we want as it prevents SGID bit clearing and the mode has been properly set by posix_acl_create() anyway. Fixes: 073931017b49d9458aa351605b43a7e34598caef Signed-off-by: Theodore Ts'o Signed-off-by: Jan Kara Reviewed-by: Andreas Gruenbacher [bwh: Backported to 3.16: - Keep using ext4_current_time() - Adjust context] Signed-off-by: Ben Hutchings

ext4: preserve i_mode if __ext4_set_acl() fails

2017-10-12T14:28:09+00:00

commit 397e434176bb62bc6068d2210af1d876c6212a7e upstream. When changing a file's acl mask, __ext4_set_acl() will first set the group bits of i_mode to the value of the mask, and only then set the actual extended attribute representing the new acl. If the second part fails (due to lack of space, for example) and the file had no acl attribute to begin with, the system will from now on assume that the mask permission bits are actual group permission bits, potentially granting access to the wrong users. Prevent this by only changing the inode mode after the acl has been set. Signed-off-by: Ernesto A. Fernández Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara [bwh: Backported to 3.16: keep using ext4_current_time()] Signed-off-by: Ben Hutchings

posix_acl: Clear SGID bit when setting file permissions

2016-11-20T01:17:38+00:00

commit 073931017b49d9458aa351605b43a7e34598caef upstream. When file permissions are modified via chmod(2) and the user is not in the owning group or capable of CAP_FSETID, the setgid bit is cleared in inode_change_ok(). Setting a POSIX ACL via setxattr(2) sets the file permissions as well as the new ACL, but doesn't clear the setgid bit in a similar way; this allows to bypass the check in chmod(2). Fix that. References: CVE-2016-7097 Reviewed-by: Christoph Hellwig Reviewed-by: Jeff Layton Signed-off-by: Jan Kara Signed-off-by: Andreas Gruenbacher [bwh: Backported to 3.16: - Drop changes to orangefs - Adjust context - Update ext3 as well] Signed-off-by: Ben Hutchings

ext2/3/4: use generic posix ACL infrastructure

2014-01-26T04:58:19+00:00

Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Al Viro

fs: make posix_acl_create more useful

2014-01-26T04:58:18+00:00

Rename the current posix_acl_created to __posix_acl_create and add a fully featured helper to set up the ACLs on file creation that uses get_acl(). Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Al Viro

fs: make posix_acl_chmod more useful

2014-01-26T04:58:18+00:00

Rename the current posix_acl_chmod to __posix_acl_chmod and add a fully featured ACL chmod helper that uses the ->set_acl inode operation. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Al Viro

ext4: fix the number of credits needed for acl ops with inline data

2013-02-09T20:23:03+00:00

Operations which modify extended attributes may need extra journal credits if inline data is used, since there is a chance that some extended attributes may need to get pushed to an external attribute block. Changes to reflect this was made in xattr.c, but they were missed in fs/ext4/acl.c. To fix this, abstract the calculation of the number of credits needed for xattr operations to an inline function defined in ext4_jbd2.h, and use it in acl.c and xattr.c. Also move the function declarations used in inline.c from xattr.h (where they are non-obviously hidden, and caused problems since ext4_jbd2.h needs to use the function ext4_has_inline_data), and move them to ext4.h. Signed-off-by: "Theodore Ts'o" Reviewed-by: Tao Ma Reviewed-by: Jan Kara

ext4: pass context information to jbd2__journal_start()

2013-02-09T02:59:22+00:00

So we can better understand what bits of ext4 are responsible for long-running jbd2 handles, use jbd2__journal_start() so we can pass context information for logging purposes. The recommended way for finding the longer-running handles is: T=/sys/kernel/debug/tracing EVENT=$T/events/jbd2/jbd2_handle_stats echo "interval > 5" > $EVENT/filter echo 1 > $EVENT/enable ./run-my-fs-benchmark cat $T/trace > /tmp/problem-handles This will list handles that were active for longer than 20ms. Having longer-running handles is bad, because a commit started at the wrong time could stall for those 20+ milliseconds, which could delay an fsync() or an O_SYNC operation. Here is an example line from the trace file describing a handle which lived on for 311 jiffies, or over 1.2 seconds: postmark-2917 [000] .... 196.435786: jbd2_handle_stats: dev 254,32 tid 570 type 2 line_no 2541 interval 311 sync 0 requested_blocks 1 dirtied_blocks 0 Signed-off-by: "Theodore Ts'o"

ext4: fix memory leak in ext4_xattr_set_acl()'s error path

2012-11-08T20:11:11+00:00

In ext4_xattr_set_acl(), if ext4_journal_start() returns an error, posix_acl_release() will not be called for 'acl' which may result in a memory leak. This patch fixes that. Reviewed-by: Lukas Czerner Signed-off-by: Eugene Shatokhin Signed-off-by: "Theodore Ts'o" Cc: stable@vger.kernel.org

userns: Convert extN to support kuids and kgids in posix acls

2012-09-18T08:01:36+00:00

Convert ext2, ext3, and ext4 to fully support the posix acl changes, using e_uid e_gid instead e_id. Enabled building with posix acls enabled, all filesystems supporting user namespaces, now also support posix acls when user namespaces are enabled. Cc: Theodore Tso Cc: Andrew Morton Cc: Andreas Dilger Cc: Jan Kara Cc: Al Viro Signed-off-by: Eric W. Biederman