kernel.git/drivers/char/tty_io.c, branch linux-2.6.23.y

tty: dont needlessly cast kmalloc() return value

2007-08-24T04:39:41Z

kmalloc() hands us a void pointer, we don't need to cast it. Signed-off-by: Jesper Juhl Signed-off-by: Linus Torvalds

fix serial buffer memory leak

2007-08-11T22:47:41Z

Patch c5c34d4862e18ef07c1276d233507f540fb5a532 (tty: flush flip buffer on ldisc input queue flush) introduces a race condition which can lead to memory leaks. The problem can be triggered when tcflush() is called when data are being pushed to the line discipline driver by flush_to_ldisc(). flush_to_ldisc() releases tty->buf.lock when calling the line discipline receive_buf function. At that poing tty_buffer_flush() kicks in and sets both tty->buf.head and tty->buf.tail to NULL. When flush_to_ldisc() finishes, it restores tty->buf.head but doesn't touch tty->buf.tail. This corrups the buffer queue, and the next call to tty_buffer_request_room() will allocate a new buffer and overwrite tty->buf.head. The previous buffer is then lost forever without being released. (Thanks to Laurent for the above text, for finding, disgnosing and reporting the bug) - Use tty->flags bits for the flush status. - Wait for the flag to clear again before returning - Fix the doc error noted - Fix flush of empty queue leaving stale flushpending [akpm@linux-foundation.org: cleanup] Signed-off-by: Alan Cox Acked-by: Paul Fulghum Cc: Laurent Pinchart Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Audit: add TTY input auditing

2007-07-16T16:05:47Z

Add TTY input auditing, used to audit system administrator's actions. This is required by various security standards such as DCID 6/3 and PCI to provide non-repudiation of administrator's actions and to allow a review of past actions if the administrator seems to overstep their duties or if the system becomes misconfigured for unknown reasons. These requirements do not make it necessary to audit TTY output as well. Compared to an user-space keylogger, this approach records TTY input using the audit subsystem, correlated with other audit events, and it is completely transparent to the user-space application (e.g. the console ioctls still work). TTY input auditing works on a higher level than auditing all system calls within the session, which would produce an overwhelming amount of mostly useless audit events. Add an "audit_tty" attribute, inherited across fork (). Data read from TTYs by process with the attribute is sent to the audit subsystem by the kernel. The audit netlink interface is extended to allow modifying the audit_tty attribute, and to allow sending explanatory audit events from user-space (for example, a shell might send an event containing the final command, after the interactive command-line editing and history expansion is performed, which might be difficult to decipher from the TTY input alone). Because the "audit_tty" attribute is inherited across fork (), it would be set e.g. for sshd restarted within an audited session. To prevent this, the audit_tty attribute is cleared when a process with no open TTY file descriptors (e.g. after daemon startup) opens a TTY. See https://www.redhat.com/archives/linux-audit/2007-June/msg00000.html for a more detailed rationale document for an older version of this patch. [akpm@linux-foundation.org: build fix] Signed-off-by: Miloslav Trmac Cc: Al Viro Cc: Alan Cox Cc: Paul Fulghum Cc: Casey Schaufler Cc: Steve Grubb Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

tty_io: Use kzalloc

2007-07-16T16:05:43Z

Also remove needless casts. Signed-off-by: Jean Delvare Acked-by: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Prevent an O_NDELAY writer from blocking when a tty write is blocked by the tty atomic writer mutex

2007-07-16T16:05:41Z

Without this a tty write could block if a previous blocking tty write was in progress on the same tty and blocked by a line discipline or hardware event. Originally found and reported by Dave Johnson. Signed-off-by: Alan Cox Acked-by: Dave Johnson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

tty: restore locked ioctl file op

2007-06-16T20:16:15Z

Restore tty locked ioctl handler which was replaced with an unlocked ioctl handler in hung_up_tty_fops by the patch: commit e10cc1df1d2014f68a4bdcf73f6dd122c4561f94 Author: Paul Fulghum Date: Thu May 10 22:22:50 2007 -0700 tty: add compat_ioctl This was reported in: [Bug 8473] New: Oops: 0010 [1] SMP The bug is caused by switching to hung_up_tty_fops in do_tty_hangup. An ioctl call can be waiting on BLK after testing for existence of the locked ioctl handler in the normal tty fops, but before calling the locked ioctl handler. If a hangup occurs at that point, the locked ioctl fop is NULL and an oops occurs. (akpm: we can remove my debugging code from do_ioctl() now, but it'll be OK to do that for 2.6.23) Signed-off-by: Paul Fulghum Cc: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

tty: fix leakage of -ERESTARTSYS to userland

2007-06-01T15:18:29Z

Spotted by Satoru Takeuchi. kill_pgrp(task_pgrp(current)) sends the signal to the current's thread group, but can choose any sub-thread as a target for signal_wake_up(). This means that job_control() and tty_check_change() may return -ERESTARTSYS without signal_pending(). Signed-off-by: Oleg Nesterov Cc: Satoru Takeuchi Cc: Roland McGrath Cc: Alan Cox Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

tty: flush flip buffer on ldisc input queue flush

2007-05-12T17:55:39Z

Flush the tty flip buffer when the line discipline input queue is flushed, including the user call tcflush(TCIFLUSH/TCIOFLUSH). This prevents unexpected stale data after a user application calls tcflush(). Signed-off-by: Alan Cox Cc: Antonino Ingargiola Signed-off-by: Paul Fulghum Cc: Theodore Ts'o Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[TTY]: Export proc_clear_tty() to modulea.

2007-05-12T04:39:23Z

A use was added to the solaris syscall module which can be built modular. Signed-off-by: David S. Miller

tty: add compat_ioctl

2007-05-11T15:29:35Z

Add compat_ioctl method for tty code to allow processing of 32 bit ioctl calls on 64 bit systems by tty core, tty drivers, and line disciplines. Based on patch by Arnd Bergmann: http://www.uwsg.iu.edu/hypermail/linux/kernel/0511.0/1732.html [akpm@linux-foundation.org: make things static] Signed-off-by: Paul Fulghum Acked-by: Arnd Bergmann Cc: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds