There are 2 scenarios which would trigger infinite loop:
1. None log is recorded, then dumplog with "-n", for example:
debugfs -R "logdump -O -n 10" /dev/xxx
while /dev/xxx has no valid log recorded.
2. The log area is full and cycle write is triggered, then dumplog with
debugfs -R "logdump -aOS" /dev/xxx
This patch add a new flag "reverse_flag" to mark if logdump has reached
to tail of logarea, it is default false, and set in macro WRAP().
If reverse_flag is true, and we comes to first_transaction_blocknr
again, just break the logdump loop.
Signed-off-by: Wenchao Hao <[email protected]>
---
debugfs/logdump.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/debugfs/logdump.c b/debugfs/logdump.c
index b600228e..05ea839a 100644
--- a/debugfs/logdump.c
+++ b/debugfs/logdump.c
@@ -52,6 +52,7 @@ static int64_t dump_counts;
static blk64_t block_to_dump, bitmap_to_dump, inode_block_to_dump;
static unsigned int group_to_dump, inode_offset_to_dump;
static ext2_ino_t inode_to_dump;
+static bool reverse_flag;
struct journal_source
{
@@ -80,8 +81,10 @@ static void dump_fc_block(FILE *out_file, char *buf, int blocksize,
static void do_hexdump (FILE *, char *, int);
#define WRAP(jsb, blocknr, maxlen) \
- if (blocknr >= (maxlen)) \
- blocknr -= (maxlen - be32_to_cpu((jsb)->s_first));
+ if (blocknr >= (maxlen)) { \
+ blocknr -= (maxlen - be32_to_cpu((jsb)->s_first)); \
+ reverse_flag = true; \
+ }
void do_logdump(int argc, char **argv, int sci_idx EXT2FS_ATTR((unused)),
void *infop EXT2FS_ATTR((unused)))
@@ -115,6 +118,7 @@ void do_logdump(int argc, char **argv, int sci_idx EXT2FS_ATTR((unused)),
inode_block_to_dump = ANY_BLOCK;
inode_to_dump = -1;
dump_counts = -1;
+ reverse_flag = false;
reset_getopt();
while ((c = getopt (argc, argv, "ab:ci:f:OsSn:")) != EOF) {
@@ -477,8 +481,7 @@ static void dump_journal(char *cmdname, FILE *out_file,
if (dump_old && (dump_counts != -1) && (cur_counts >= dump_counts))
break;
- if ((blocknr == first_transaction_blocknr) &&
- (cur_counts != 0) && dump_old && (dump_counts != -1)) {
+ if ((blocknr == first_transaction_blocknr) && dump_old && reverse_flag) {
fprintf(out_file, "Dump all %lld journal records.\n",
(long long) cur_counts);
break;
--
2.32.0
On 2023/11/17 18:23, Wenchao Hao wrote:
> There are 2 scenarios which would trigger infinite loop:
>
> 1. None log is recorded, then dumplog with "-n", for example:
> debugfs -R "logdump -O -n 10" /dev/xxx
> while /dev/xxx has no valid log recorded.
> 2. The log area is full and cycle write is triggered, then dumplog with
> debugfs -R "logdump -aOS" /dev/xxx
>
> This patch add a new flag "reverse_flag" to mark if logdump has reached
> to tail of logarea, it is default false, and set in macro WRAP().
>
> If reverse_flag is true, and we comes to first_transaction_blocknr
> again, just break the logdump loop.
Friendly ping...
>
> Signed-off-by: Wenchao Hao <[email protected]>
> ---
> debugfs/logdump.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/debugfs/logdump.c b/debugfs/logdump.c
> index b600228e..05ea839a 100644
> --- a/debugfs/logdump.c
> +++ b/debugfs/logdump.c
> @@ -52,6 +52,7 @@ static int64_t dump_counts;
> static blk64_t block_to_dump, bitmap_to_dump, inode_block_to_dump;
> static unsigned int group_to_dump, inode_offset_to_dump;
> static ext2_ino_t inode_to_dump;
> +static bool reverse_flag;
>
> struct journal_source
> {
> @@ -80,8 +81,10 @@ static void dump_fc_block(FILE *out_file, char *buf, int blocksize,
> static void do_hexdump (FILE *, char *, int);
>
> #define WRAP(jsb, blocknr, maxlen) \
> - if (blocknr >= (maxlen)) \
> - blocknr -= (maxlen - be32_to_cpu((jsb)->s_first));
> + if (blocknr >= (maxlen)) { \
> + blocknr -= (maxlen - be32_to_cpu((jsb)->s_first)); \
> + reverse_flag = true; \
> + }
>
> void do_logdump(int argc, char **argv, int sci_idx EXT2FS_ATTR((unused)),
> void *infop EXT2FS_ATTR((unused)))
> @@ -115,6 +118,7 @@ void do_logdump(int argc, char **argv, int sci_idx EXT2FS_ATTR((unused)),
> inode_block_to_dump = ANY_BLOCK;
> inode_to_dump = -1;
> dump_counts = -1;
> + reverse_flag = false;
>
> reset_getopt();
> while ((c = getopt (argc, argv, "ab:ci:f:OsSn:")) != EOF) {
> @@ -477,8 +481,7 @@ static void dump_journal(char *cmdname, FILE *out_file,
> if (dump_old && (dump_counts != -1) && (cur_counts >= dump_counts))
> break;
>
> - if ((blocknr == first_transaction_blocknr) &&
> - (cur_counts != 0) && dump_old && (dump_counts != -1)) {
> + if ((blocknr == first_transaction_blocknr) && dump_old && reverse_flag) {
> fprintf(out_file, "Dump all %lld journal records.\n",
> (long long) cur_counts);
> break;
On Fri, 17 Nov 2023 18:23:15 +0800, Wenchao Hao wrote:
> There are 2 scenarios which would trigger infinite loop:
>
> 1. None log is recorded, then dumplog with "-n", for example:
> debugfs -R "logdump -O -n 10" /dev/xxx
> while /dev/xxx has no valid log recorded.
> 2. The log area is full and cycle write is triggered, then dumplog with
> debugfs -R "logdump -aOS" /dev/xxx
>
> [...]
Applied, thanks!
[1/1] debugfs: Fix infinite loop when dump log
commit: 272173a300822b5cfe19bef597609523baab0c66
(I renamed reverse_flag to wrapped_flag to make things clearer.)
Best regards,
--
Theodore Ts'o <[email protected]>