在 2020年12月23日 10:31, crash-utility-request(a)redhat.com 写道:
Date: Wed, 23 Dec 2020 02:31:24 +0000
From: ??? <zhaoqianli(a)xiaomi.com>
To: =?gb2312?B?SEFHSU8gS0FaVUhJVE8oyGPOsqGh0rvIyik=?=
<k-hagio-ab(a)nec.com>, "Discussion list for crash utility usage,
maintenance and development" <crash-utility(a)redhat.com>
Subject: Re: [Crash-utility] [External Mail]RE: [PATCH V2] netdump:
fix regression for tiny kdump files
Message-ID: <e4cc6f753b2c428d9f0f0c0362567de5(a)xiaomi.com>
Content-Type: text/plain; charset="gb2312"
Hi, Lianbo
> For the checking condition, I would recommend using the following methods, what do
you think?
>
> + if (size != SAFE_NETDUMP_ELF_HEADER_SIZE &&
> + size != MIN_NETDUMP_ELF_HEADER_SIZE) {
I agrre with Kazu, if use "size !=
MIN_NETDUMP_ELF_HEADER_SIZE/SAFE_NETDUMP_ELF_HEADER_SIZE" this issue can not be
fixed, size is equal to or more than MIN_NETDUMP_ELF_HEADER_SIZE is valid.
That's true, I just knew what it happened. Thanks for the explanation.
> In addition, would you mind updating another error output in the
is_netdump()? For example:
>
> size = SAFE_NETDUMP_ELF_HEADER_SIZE;
> if ((eheader = (char *)malloc(size)) == NULL) {
> - fprintf(stderr, "cannot malloc minimum ELF header
buffer\n");
> + fprintf(stderr, "cannot malloc ELF header buffer\n");
> clean_exit(1);
> }
Ok.
How about below patch set?
Looks good to me.
Acked by: Lianbo Jiang <lijian(a)redhat.>
>From 5ec6ac06ba7fd32e96463a54ebc3f733f1054a90 Mon Sep 17 00:00:00
2001
From: Qianli Zhao <zhaoqianli(a)xiaomi.com>
Date: Mon, 30 Nov 2020 17:17:32 +0800
Subject: [PATCH] netdump: fix regression for tiny kdump files
Commit f42db6a33f0e ("Support core files with "unusual" layout")
increased the minimal file size from MIN_NETDUMP_ELF_HEADER_SIZE to
SAFE_NETDUMP_ELF_HEADER_SIZE which can lead to crash rejecting
raw RAM dumpfiles
Fix that by erroring out only if we get less than
MIN_NETDUMP_ELF_HEADER_SIZE bytes.
Signed-off-by: Qianli Zhao <zhaoqianli(a)xiaomi.com>
---
netdump.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/netdump.c b/netdump.c
index c76d9dd..ca9b459 100644
--- a/netdump.c
+++ b/netdump.c
@@ -119,7 +119,8 @@ is_netdump(char *file, ulong source_query)
Elf64_Phdr *load64;
char *eheader, *sect0;
char buf[BUFSIZE];
- size_t size, len, tot;
+ ssize_t size;
+ size_t len, tot;
Elf32_Off offset32;
Elf64_Off offset64;
ulong format;
@@ -134,7 +135,7 @@ is_netdump(char *file, ulong source_query)
size = SAFE_NETDUMP_ELF_HEADER_SIZE;
if ((eheader = (char *)malloc(size)) == NULL) {
- fprintf(stderr, "cannot malloc minimum ELF header buffer\n");
+ fprintf(stderr, "cannot malloc ELF header buffer\n");
clean_exit(1);
}
@@ -142,10 +143,14 @@ is_netdump(char *file, ulong source_query)
if (!read_flattened_format(fd, 0, eheader, size))
goto bailout;
} else {
- if (read(fd, eheader, size) != size) {
+ size = read(fd, eheader, size);
+ if (size < 0) {
sprintf(buf, "%s: ELF header read", file);
perror(buf);
goto bailout;
+ } else if (size < MIN_NETDUMP_ELF_HEADER_SIZE) {
+ fprintf(stderr, "%s: file too small!\n", file);
+ goto bailout;
}
}
--
2.7.4