user/sven/linux.git/kernel, branch v4.1.6

signal: fix information leak in copy_siginfo_from_user32

2015-08-17T03:52:26Z

commit 3c00cb5e68dc719f2fc73a33b1b230aadfcb1309 upstream. This function can leak kernel stack data when the user siginfo_t has a positive si_code value. The top 16 bits of si_code descibe which fields in the siginfo_t union are active, but they are treated inconsistently between copy_siginfo_from_user32, copy_siginfo_to_user32 and copy_siginfo_to_user. copy_siginfo_from_user32 is called from rt_sigqueueinfo and rt_tgsigqueueinfo in which the user has full control overthe top 16 bits of si_code. This fixes the following information leaks: x86: 8 bytes leaked when sending a signal from a 32-bit process to itself. This leak grows to 16 bytes if the process uses x32. (si_code = __SI_CHLD) x86: 100 bytes leaked when sending a signal from a 32-bit process to a 64-bit process. (si_code = -1) sparc: 4 bytes leaked when sending a signal from a 32-bit process to a 64-bit process. (si_code = any) parsic and s390 have similar bugs, but they are not vulnerable because rt_[tg]sigqueueinfo have checks that prevent sending a positive si_code to a different process. These bugs are also fixed for consistency. Signed-off-by: Amanieu d'Antras Cc: Oleg Nesterov Cc: Ingo Molnar Cc: Russell King Cc: Ralf Baechle Cc: Benjamin Herrenschmidt Cc: Chris Metcalf Cc: Paul Mackerras Cc: Michael Ellerman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

signal: fix information leak in copy_siginfo_to_user

2015-08-17T03:52:26Z

commit 26135022f85105ad725cda103fa069e29e83bd16 upstream. This function may copy the si_addr_lsb, si_lower and si_upper fields to user mode when they haven't been initialized, which can leak kernel stack data to user mode. Just checking the value of si_code is insufficient because the same si_code value is shared between multiple signals. This is solved by checking the value of si_signo in addition to si_code. Signed-off-by: Amanieu d'Antras Cc: Oleg Nesterov Cc: Ingo Molnar Cc: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

ftrace: Fix breakage of set_ftrace_pid

2015-08-10T19:21:55Z

commit e3eea1404f5ff7a2ceb7b5e7ba412a6fd94f2935 upstream. Commit 4104d326b670 ("ftrace: Remove global function list and call function directly") simplified the ftrace code by removing the global_ops list with a new design. But this cleanup also broke the filtering of PIDs that are added to the set_ftrace_pid file. Add back the proper hooks to have pid filtering working once again. Reported-by: Matt Fleming Reported-by: Richard Weinberger Tested-by: Matt Fleming Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

genirq: Prevent resend to interrupts marked IRQ_NESTED_THREAD

2015-08-10T19:21:53Z

commit 75a06189fc508a2acf470b0b12710362ffb2c4b1 upstream. The resend mechanism happily calls the interrupt handler of interrupts which are marked IRQ_NESTED_THREAD from softirq context. This can result in crashes because the interrupt handler is not the proper way to invoke the device handlers. They must be invoked via handle_nested_irq. Prevent the resend even if the interrupt has no valid parent irq set. Its better to have a lost interrupt than a crashing machine. Reported-by: Uwe Kleine-König Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

security_syslog() should be called once only

2015-08-03T16:29:15Z

commit d194e5d666225b04c7754471df0948f645b6ab3a upstream. The final version of commit 637241a900cb ("kmsg: honor dmesg_restrict sysctl on /dev/kmsg") lost few hooks, as result security_syslog() are processed incorrectly: - open of /dev/kmsg checks syslog access permissions by using check_syslog_permissions() where security_syslog() is not called if dmesg_restrict is set. - syslog syscall and /proc/kmsg calls do_syslog() where security_syslog can be executed twice (inside check_syslog_permissions() and then directly in do_syslog()) With this patch security_syslog() is called once only in all syslog-related operations regardless of dmesg_restrict value. Fixes: 637241a900cb ("kmsg: honor dmesg_restrict sysctl on /dev/kmsg") Signed-off-by: Vasily Averin Cc: Kees Cook Cc: Josh Boyer Cc: Eric Paris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

PM / sleep: Increase default DPM watchdog timeout to 60

2015-08-03T16:29:15Z

commit fff3b16d2754a061a3549c4307a186423a0128fd upstream. Many harddisks (mostly WD ones) have firmware problems and take too long, more than 10 seconds, to resume from suspend. And this often exceeds the default DPM watchdog timeout (12 seconds), resulting in a kernel panic out of sudden. Since most distros just take the default as is, we should give a bit more safer value. This patch increases the default value from 12 seconds to one minute, which has been confirmed to be long enough for such problematic disks. Link: https://bugzilla.kernel.org/show_bug.cgi?id=91921 Fixes: 70fea60d888d (PM / Sleep: Detect device suspend/resume lockup and log event) Signed-off-by: Takashi Iwai Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

tracing: Have branch tracer use recursive field of task struct

2015-08-03T16:29:12Z

commit 6224beb12e190ff11f3c7d4bf50cb2922878f600 upstream. Fengguang Wu's tests triggered a bug in the branch tracer's start up test when CONFIG_DEBUG_PREEMPT set. This was because that config adds some debug logic in the per cpu field, which calls back into the branch tracer. The branch tracer has its own recursive checks, but uses a per cpu variable to implement it. If retrieving the per cpu variable calls back into the branch tracer, you can see how things will break. Instead of using a per cpu variable, use the trace_recursion field of the current task struct. Simply set a bit when entering the branch tracing and clear it when leaving. If the bit is set on entry, just don't do the tracing. There's also the case with lockdep, as the local_irq_save() called before the recursion can also trigger code that can call back into the function. Changing that to a raw_local_irq_save() will protect that as well. This prevents the recursion and the inevitable crash that follows. Link: http://lkml.kernel.org/r/20150630141803.GA28071@wfg-t540p.sh.intel.com Reported-by: Fengguang Wu Tested-by: Fengguang Wu Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing: Fix typo from "static inlin" to "static inline"

2015-08-03T16:29:12Z

commit cc9e4bde03f2b4cfba52406c021364cbd2a4a0f3 upstream. The trace.h header when called without CONFIG_EVENT_TRACING enabled (seldom done), will not compile because of a typo in the protocol of trace_event_enum_update(). Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing/filter: Do not allow infix to exceed end of string

2015-08-03T16:29:12Z

commit 6b88f44e161b9ee2a803e5b2b1fbcf4e20e8b980 upstream. While debugging a WARN_ON() for filtering, I found that it is possible for the filter string to be referenced after its end. With the filter: # echo '>' > /sys/kernel/debug/events/ext4/ext4_truncate_exit/filter The filter_parse() function can call infix_get_op() which calls infix_advance() that updates the infix filter pointers for the cnt and tail without checking if the filter is already at the end, which will put the cnt to zero and the tail beyond the end. The loop then calls infix_next() that has ps->infix.cnt--; return ps->infix.string[ps->infix.tail++]; The cnt will now be below zero, and the tail that is returned is already passed the end of the filter string. So far the allocation of the filter string usually has some buffer that is zeroed out, but if the filter string is of the exact size of the allocated buffer there's no guarantee that the charater after the nul terminating character will be zero. Luckily, only root can write to the filter. Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing/filter: Do not WARN on operand count going below zero

2015-08-03T16:29:12Z

commit b4875bbe7e68f139bd3383828ae8e994a0df6d28 upstream. When testing the fix for the trace filter, I could not come up with a scenario where the operand count goes below zero, so I added a WARN_ON_ONCE(cnt < 0) to the logic. But there is legitimate case that it can happen (although the filter would be wrong). # echo '>' > /sys/kernel/debug/events/ext4/ext4_truncate_exit/filter That is, a single operation without any operands will hit the path where the WARN_ON_ONCE() can trigger. Although this is harmless, and the filter is reported as a error. But instead of spitting out a warning to the kernel dmesg, just fail nicely and report it via the proper channels. Link: http://lkml.kernel.org/r/558C6082.90608@oracle.com Reported-by: Vince Weaver Reported-by: Sasha Levin Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman