From: Alan Modra <amodra@gmail.com>
To: binutils@sourceware.org
Subject: asan : use of uninitialized value in buffer_and_nest
Date: Wed, 16 Feb 2022 22:01:32 +1030 [thread overview]
Message-ID: <YgzglDWZ6Pk9vpOj@squeak.grove.modra.org> (raw)
* macro.c (buffer_and_nest): Don't read past end of string buffer.
diff --git a/gas/macro.c b/gas/macro.c
index 9327a6dea76..cbb9574fd66 100644
--- a/gas/macro.c
+++ b/gas/macro.c
@@ -184,14 +184,24 @@ buffer_and_nest (const char *from, const char *to, sb *ptr,
{
if (! flag_m68k_mri && ptr->ptr[i] == '.')
i++;
- if (from == NULL
- && strncasecmp (ptr->ptr + i, "IRPC", from_len = 4) != 0
- && strncasecmp (ptr->ptr + i, "IRP", from_len = 3) != 0
- && strncasecmp (ptr->ptr + i, "IREPC", from_len = 5) != 0
- && strncasecmp (ptr->ptr + i, "IREP", from_len = 4) != 0
- && strncasecmp (ptr->ptr + i, "REPT", from_len = 4) != 0
- && strncasecmp (ptr->ptr + i, "REP", from_len = 3) != 0)
- from_len = 0;
+ if (from == NULL)
+ {
+ size_t len = ptr->len - i;
+ if (len >= 5 && strncasecmp (ptr->ptr + i, "IREPC", 5) == 0)
+ from_len = 5;
+ else if (len >= 4 && strncasecmp (ptr->ptr + i, "IREP", 4) == 0)
+ from_len = 4;
+ else if (len >= 4 && strncasecmp (ptr->ptr + i, "IRPC", 4) == 0)
+ from_len = 4;
+ else if (len >= 4 && strncasecmp (ptr->ptr + i, "REPT", 4) == 0)
+ from_len = 4;
+ else if (len >= 3 && strncasecmp (ptr->ptr + i, "IRP", 3) == 0)
+ from_len = 3;
+ else if (len >= 3 && strncasecmp (ptr->ptr + i, "REP", 3) == 0)
+ from_len = 3;
+ else
+ from_len = 0;
+ }
if ((from != NULL
? strncasecmp (ptr->ptr + i, from, from_len) == 0
: from_len > 0)
@@ -199,7 +209,8 @@ buffer_and_nest (const char *from, const char *to, sb *ptr,
|| ! (is_part_of_name (ptr->ptr[i + from_len])
|| is_name_ender (ptr->ptr[i + from_len]))))
depth++;
- if (strncasecmp (ptr->ptr + i, to, to_len) == 0
+ if (ptr->len - i >= to_len
+ && strncasecmp (ptr->ptr + i, to, to_len) == 0
&& (ptr->len == (i + to_len)
|| ! (is_part_of_name (ptr->ptr[i + to_len])
|| is_name_ender (ptr->ptr[i + to_len]))))
--
Alan Modra
Australia Development Lab, IBM
next reply other threads:[~2022-02-16 11:31 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-16 11:31 Alan Modra [this message]
2022-03-17 11:00 asan: " Alan Modra
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