Patch "PM / sleep: declare __tracedata symbols as char[] rather than char" has been added to the 4.4-stable tree
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This is a note to let you know that I've just added the patch titled
PM / sleep: declare __tracedata symbols as char[] rather than char
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pm-sleep-declare-__tracedata-symbols-as-char-rather-than-char.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
Quoted 1 line
From
f97238373b8662a6d580e204df2e7bcbfa43e27aMon Sep 17 00:00:00 2001
From: Eric Biggers <[email protected]>
Date: Sun, 24 Jan 2016 20:08:52 -0600
Subject: PM / sleep: declare __tracedata symbols as char[] rather than char
From: Eric Biggers <[email protected]>
commit f97238373b8662a6d580e204df2e7bcbfa43e27a upstream.
Accessing more than one byte from a symbol declared simply 'char' is undefined behavior, as reported by UBSAN:
UBSAN: Undefined behaviour in drivers/base/power/trace.c:178:18 load of address ffffffff8203fc78 with insufficient space for an object of type 'char'
Avoid this by declaring the symbols as arrays.
--- drivers/base/power/trace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
drivers/base/power/trace.c +2 -2
@@ -166,14 +166,14 @@ void generate_pm_trace(const void *trace }EXPORT_SYMBOL (generate_pm_trace); -extern char __tracedata_start, __tracedata_end; +extern char __tracedata_start[], __tracedata_end[];static int show_file_hash (unsigned int value) {int match;char *tracedata; match =0 ; -for (tracedata = &__tracedata_start ; tracedata < &__tracedata_end ; +for (tracedata = __tracedata_start ; tracedata < __tracedata_end ; tracedata +=2 +sizeof (unsigned long )) {unsigned short lineno = *(unsigned short *)tracedata;const char *file = *(const char **)(tracedata +2 );
Patches currently in stable-queue which might be from [email protected] are
queue-4.4/pm-sleep-declare-__tracedata-symbols-as-char-rather-than-char.patch