lkml.org 
[lkml]   [2021]   [Jun]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] arm64: ftrace: don't dereference a probably invalid address
Date
Address in __mcount_loc may be invalid if somthing goes wrong.
On our arm64 platform, the bug in recordmcount make kernel
crash in ftrace_init().

https://lore.kernel.org/lkml/20210607023839.26387-1-mark-pk.tsai@mediatek.com/

Return -EFAULT if we are dealing with out-of-range condition
to prevent dereference the invalid address in ftrace_bug(),
then the kernel can disable ftrace safely for problematic
__mcount_loc.

Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
---
arch/arm64/kernel/ftrace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
index b5d3ddaf69d9..98bec8445a58 100644
--- a/arch/arm64/kernel/ftrace.c
+++ b/arch/arm64/kernel/ftrace.c
@@ -201,7 +201,7 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
preempt_enable();

if (WARN_ON(!mod))
- return -EINVAL;
+ return -EFAULT;
}

/*
--
2.18.0
\
 
 \ /
  Last update: 2021-06-07 05:24    [W:0.061 / U:0.220 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site