linux.git/kernel/fail_function.c, branch v6.6.132

kernel/fail_function: fix memory leak with using debugfs_lookup()

2023-02-08T12:36:22+00:00

When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time.  To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.

Cc: Andrew Morton 
Reviewed-by: Yang Yingliang 
Link: https://lore.kernel.org/r/20230202151633.2310897-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

fail_function: fix wrong use of fei_attr_remove()

2022-09-12T04:55:11+00:00

If register_kprobe() fails, the new attr is not added to the list yet, so
it should call fei_attr_free() intstead.

Link: https://lkml.kernel.org/r/20220826073337.2085798-3-yangyingliang@huawei.com
Fixes: 4b1a29a7f542 ("error-injection: Support fault injection framework")
Signed-off-by: Yang Yingliang 
Reviewed-by: Andrew Morton 
Signed-off-by: Andrew Morton

fail_function: refactor code of checking return value of register_kprobe()

2022-09-12T04:55:11+00:00

Refactor the error handling of register_kprobe() to improve readability. 
No functional change.

Link: https://lkml.kernel.org/r/20220826073337.2085798-2-yangyingliang@huawei.com
Signed-off-by: Yang Yingliang 
Reviewed-by: Andrew Morton 
Signed-off-by: Andrew Morton

fail_function: switch to memdup_user_nul() helper

2022-09-12T04:55:10+00:00

Use memdup_user_nul() helper instead of open-coding to simplify the code.

Link: https://lkml.kernel.org/r/20220826073337.2085798-1-yangyingliang@huawei.com
Signed-off-by: Yang Yingliang 
Reviewed-by: Andrew Morton 
Signed-off-by: Andrew Morton

fault-injection: handle EI_ETYPE_TRUE

2020-12-16T06:46:19+00:00

Commit af3b854492f351d1 ("mm/page_alloc.c: allow error injection")
introduced EI_ETYPE_TRUE, but did not extend

 * lib/error-inject.c:error_type_string(), and
 * kernel/fail_function.c:adjust_error_retval()

to accommodate for this change.

Handle EI_ETYPE_TRUE in both functions appropriately by
 * returning "TRUE" in error_type_string(),
 * adjusting the return value to true (1) in adjust_error_retval().

Furthermore, simplify the logic of handling EI_ETYPE_NULL in
adjust_error_retval().

Link: https://lkml.kernel.org/r/njB1czX0ZgWPR9h61euHIBb5bEyePw9D4D2m3i5lc9Cl96P8Q1308dTcmsEZW7Vtz3Ifz4do-rOtSfuFTyGoEDYokkK2aUqBePVptzZEWfU=@protonmail.com
Signed-off-by: Barnabás Pőcze 
Acked-by: Masami Hiramatsu 
Reviewed-by: Akinobu Mita 
Cc: "Naveen N. Rao" 
Cc: Anil S Keshavamurthy 
Cc: "David S. Miller" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fail_function: Remove a redundant mutex unlock

2020-11-19T19:58:16+00:00

Fix a mutex_unlock() issue where before copy_from_user() is
not called mutex_locked.

Fixes: 4b1a29a7f542 ("error-injection: Support fault injection framework")
Reported-by: Hulk Robot 
Signed-off-by: Luo Meng 
Signed-off-by: Masami Hiramatsu 
Signed-off-by: Alexei Starovoitov 
Acked-by: Masami Hiramatsu 
Link: https://lore.kernel.org/bpf/160570737118.263807.8358435412898356284.stgit@devnote2

fail_function: no need to check return value of debugfs_create functions

2019-06-03T13:49:06+00:00

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Kees Cook 
Cc: Josef Bacik 
Cc: Thomas Gleixner 
Cc: "Naveen N. Rao" 
Cc: zhong jiang 
Acked-by: Masami Hiramatsu 
Signed-off-by: Greg Kroah-Hartman

treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively

2019-04-09T12:19:06+00:00

%pF and %pf are functionally equivalent to %pS and %ps conversion
specifiers. The former are deprecated, therefore switch the current users
to use the preferred variant.

The changes have been produced by the following command:

	git grep -l '%p[fF]' | grep -v '^\(tools\|Documentation\)/' | \
	while read i; do perl -i -pe 's/%pf/%ps/g; s/%pF/%pS/g;' $i; done

And verifying the result.

Link: http://lkml.kernel.org/r/20190325193229.23390-1-sakari.ailus@linux.intel.com
Cc: Andy Shevchenko 
Cc: linux-arm-kernel@lists.infradead.org
Cc: sparclinux@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: xen-devel@lists.xenproject.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-nvdimm@lists.01.org
Cc: linux-pci@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: linux-btrfs@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: linux-mm@kvack.org
Cc: ceph-devel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Sakari Ailus 
Acked-by: David Sterba  (for btrfs)
Acked-by: Mike Rapoport  (for mm/memblock.c)
Acked-by: Bjorn Helgaas  (for drivers/pci)
Acked-by: Rafael J. Wysocki 
Signed-off-by: Petr Mladek

kernel/fail_function.c: remove meaningless null pointer check before debugfs_remove_recursive

2018-10-31T15:54:12+00:00

debugfs_remove_recursive() has taken the null pointer into account.  just
remove the null check before debugfs_remove_recursive().

Link: http://lkml.kernel.org/r/1537494404-16473-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang 
Acked-by: Masami Hiramatsu 
Acked-by: Kees Cook 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

bpf/error-inject/kprobes: Clear current_kprobe and enable preempt in kprobe

2018-06-21T10:33:19+00:00

Clear current_kprobe and enable preemption in kprobe
even if pre_handler returns !0.

This simplifies function override using kprobes.

Jprobe used to require to keep the preemption disabled and
keep current_kprobe until it returned to original function
entry. For this reason kprobe_int3_handler() and similar
arch dependent kprobe handers checks pre_handler result
and exit without enabling preemption if the result is !0.

After removing the jprobe, Kprobes does not need to
keep preempt disabled even if user handler returns !0
anymore.

But since the function override handler in error-inject
and bpf is also returns !0 if it overrides a function,
to balancing the preempt count, it enables preemption
and reset current kprobe by itself.

That is a bad design that is very buggy. This fixes
such unbalanced preempt-count and current_kprobes setting
in kprobes, bpf and error-inject.

Note: for powerpc and x86, this removes all preempt_disable
from kprobe_ftrace_handler because ftrace callbacks are
called under preempt disabled.

Signed-off-by: Masami Hiramatsu 
Acked-by: Thomas Gleixner 
Acked-by: Naveen N. Rao 
Cc: Alexei Starovoitov 
Cc: Ananth N Mavinakayanahalli 
Cc: Andrew Morton 
Cc: Benjamin Herrenschmidt 
Cc: Catalin Marinas 
Cc: David S. Miller 
Cc: Fenghua Yu 
Cc: Heiko Carstens 
Cc: James Hogan 
Cc: Josef Bacik 
Cc: Linus Torvalds 
Cc: Martin Schwidefsky 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Ralf Baechle 
Cc: Rich Felker 
Cc: Russell King 
Cc: Steven Rostedt 
Cc: Tony Luck 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Link: https://lore.kernel.org/lkml/152942494574.15209.12323837825873032258.stgit@devbox
Signed-off-by: Ingo Molnar