diff mbox series

[1/2] block/file-posix: fix g_file_get_contents return path

Message ID 20230604061658.49004-1-faithilikerun@gmail.com (mailing list archive)
State New, archived
Headers show
Series [1/2] block/file-posix: fix g_file_get_contents return path | expand

Commit Message

Sam Li June 4, 2023, 6:16 a.m. UTC
The g_file_get_contents() function returns a g_boolean. If it fails, the
returned value will be 0 instead of -1. Solve the issue by skipping
assigning ret value.

This issue was found by Matthew Rosato using virtio-blk-{pci,ccw} backed
by an NVMe partition e.g. /dev/nvme0n1p1 on s390x.

Signed-off-by: Sam Li <faithilikerun@gmail.com>
---
 block/file-posix.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Comments

Matthew Rosato June 7, 2023, 1:51 p.m. UTC | #1
On 6/4/23 2:16 AM, Sam Li wrote:
> The g_file_get_contents() function returns a g_boolean. If it fails, the
> returned value will be 0 instead of -1. Solve the issue by skipping
> assigning ret value.
> 
> This issue was found by Matthew Rosato using virtio-blk-{pci,ccw} backed
> by an NVMe partition e.g. /dev/nvme0n1p1 on s390x.
> 
> Signed-off-by: Sam Li <faithilikerun@gmail.com>

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>

Also tested to verify that this fix resolves the reported issue.  Thanks!
Stefan Hajnoczi June 7, 2023, 4:04 p.m. UTC | #2
On Sun, Jun 04, 2023 at 02:16:57PM +0800, Sam Li wrote:
> The g_file_get_contents() function returns a g_boolean. If it fails, the
> returned value will be 0 instead of -1. Solve the issue by skipping
> assigning ret value.
> 
> This issue was found by Matthew Rosato using virtio-blk-{pci,ccw} backed
> by an NVMe partition e.g. /dev/nvme0n1p1 on s390x.
> 
> Signed-off-by: Sam Li <faithilikerun@gmail.com>
> ---
>  block/file-posix.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)

The number of bytes returned was never used, so changing the return
value to 0 or -errno is fine:

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Matthew Rosato July 5, 2023, 2:54 p.m. UTC | #3
On 6/4/23 2:16 AM, Sam Li wrote:
> The g_file_get_contents() function returns a g_boolean. If it fails, the
> returned value will be 0 instead of -1. Solve the issue by skipping
> assigning ret value.
> 
> This issue was found by Matthew Rosato using virtio-blk-{pci,ccw} backed
> by an NVMe partition e.g. /dev/nvme0n1p1 on s390x.
> 
> Signed-off-by: Sam Li <faithilikerun@gmail.com>

Polite ping on this patch -- this issue still exists in master as of today and this patch resolves it for me.  Just want to make sure it gets into 8.1

Thanks,
Matt

> ---
>  block/file-posix.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/block/file-posix.c b/block/file-posix.c
> index ac1ed54811..0d9d179a35 100644
> --- a/block/file-posix.c
> +++ b/block/file-posix.c
> @@ -1232,7 +1232,6 @@ static int hdev_get_max_hw_transfer(int fd, struct stat *st)
>  static int get_sysfs_str_val(struct stat *st, const char *attribute,
>                               char **val) {
>      g_autofree char *sysfspath = NULL;
> -    int ret;
>      size_t len;
>  
>      if (!S_ISBLK(st->st_mode)) {
> @@ -1242,8 +1241,7 @@ static int get_sysfs_str_val(struct stat *st, const char *attribute,
>      sysfspath = g_strdup_printf("/sys/dev/block/%u:%u/queue/%s",
>                                  major(st->st_rdev), minor(st->st_rdev),
>                                  attribute);
> -    ret = g_file_get_contents(sysfspath, val, &len, NULL);
> -    if (ret == -1) {
> +    if (!g_file_get_contents(sysfspath, val, &len, NULL)) {
>          return -ENOENT;
>      }
>  
> @@ -1253,7 +1251,7 @@ static int get_sysfs_str_val(struct stat *st, const char *attribute,
>      if (*(p + len - 1) == '\n') {
>          *(p + len - 1) = '\0';
>      }
> -    return ret;
> +    return 0;
>  }
>  #endif
>
Matthew Rosato July 27, 2023, 11:46 a.m. UTC | #4
On 7/5/23 10:54 AM, Matthew Rosato wrote:
> On 6/4/23 2:16 AM, Sam Li wrote:
>> The g_file_get_contents() function returns a g_boolean. If it fails, the
>> returned value will be 0 instead of -1. Solve the issue by skipping
>> assigning ret value.
>>
>> This issue was found by Matthew Rosato using virtio-blk-{pci,ccw} backed
>> by an NVMe partition e.g. /dev/nvme0n1p1 on s390x.
>>
>> Signed-off-by: Sam Li <faithilikerun@gmail.com>
> 
> Polite ping on this patch -- this issue still exists in master as of today and this patch resolves it for me.  Just want to make sure it gets into 8.1
> 

Ping -- I can still reproduce this crash on -rc1.  Any chance this patch can get picked up for the 8.1 release?

@Sam I see you sent a v2 of only patch #2 in this series ('block/file-posix: fix wps checking in raw_co_prw')..  I wonder if this one just got forgotten since it wasn't sent as part of v2.  Maybe try a resend of this patch by itself (plus the review tags added)?

Thanks,
Matt

> 
>> ---
>>  block/file-posix.c | 6 ++----
>>  1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/block/file-posix.c b/block/file-posix.c
>> index ac1ed54811..0d9d179a35 100644
>> --- a/block/file-posix.c
>> +++ b/block/file-posix.c
>> @@ -1232,7 +1232,6 @@ static int hdev_get_max_hw_transfer(int fd, struct stat *st)
>>  static int get_sysfs_str_val(struct stat *st, const char *attribute,
>>                               char **val) {
>>      g_autofree char *sysfspath = NULL;
>> -    int ret;
>>      size_t len;
>>  
>>      if (!S_ISBLK(st->st_mode)) {
>> @@ -1242,8 +1241,7 @@ static int get_sysfs_str_val(struct stat *st, const char *attribute,
>>      sysfspath = g_strdup_printf("/sys/dev/block/%u:%u/queue/%s",
>>                                  major(st->st_rdev), minor(st->st_rdev),
>>                                  attribute);
>> -    ret = g_file_get_contents(sysfspath, val, &len, NULL);
>> -    if (ret == -1) {
>> +    if (!g_file_get_contents(sysfspath, val, &len, NULL)) {
>>          return -ENOENT;
>>      }
>>  
>> @@ -1253,7 +1251,7 @@ static int get_sysfs_str_val(struct stat *st, const char *attribute,
>>      if (*(p + len - 1) == '\n') {
>>          *(p + len - 1) = '\0';
>>      }
>> -    return ret;
>> +    return 0;
>>  }
>>  #endif
>>  
> 
>
Sam Li July 27, 2023, 11:51 a.m. UTC | #5
Matthew Rosato <mjrosato@linux.ibm.com> 于2023年7月27日周四 19:46写道:
>
> On 7/5/23 10:54 AM, Matthew Rosato wrote:
> > On 6/4/23 2:16 AM, Sam Li wrote:
> >> The g_file_get_contents() function returns a g_boolean. If it fails, the
> >> returned value will be 0 instead of -1. Solve the issue by skipping
> >> assigning ret value.
> >>
> >> This issue was found by Matthew Rosato using virtio-blk-{pci,ccw} backed
> >> by an NVMe partition e.g. /dev/nvme0n1p1 on s390x.
> >>
> >> Signed-off-by: Sam Li <faithilikerun@gmail.com>
> >
> > Polite ping on this patch -- this issue still exists in master as of today and this patch resolves it for me.  Just want to make sure it gets into 8.1
> >
>
> Ping -- I can still reproduce this crash on -rc1.  Any chance this patch can get picked up for the 8.1 release?
>
> @Sam I see you sent a v2 of only patch #2 in this series ('block/file-posix: fix wps checking in raw_co_prw')..  I wonder if this one just got forgotten since it wasn't sent as part of v2.  Maybe try a resend of this patch by itself (plus the review tags added)?

Ok, I will resend it as a separate patch.

>
> Thanks,
> Matt
>
> >
> >> ---
> >>  block/file-posix.c | 6 ++----
> >>  1 file changed, 2 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/block/file-posix.c b/block/file-posix.c
> >> index ac1ed54811..0d9d179a35 100644
> >> --- a/block/file-posix.c
> >> +++ b/block/file-posix.c
> >> @@ -1232,7 +1232,6 @@ static int hdev_get_max_hw_transfer(int fd, struct stat *st)
> >>  static int get_sysfs_str_val(struct stat *st, const char *attribute,
> >>                               char **val) {
> >>      g_autofree char *sysfspath = NULL;
> >> -    int ret;
> >>      size_t len;
> >>
> >>      if (!S_ISBLK(st->st_mode)) {
> >> @@ -1242,8 +1241,7 @@ static int get_sysfs_str_val(struct stat *st, const char *attribute,
> >>      sysfspath = g_strdup_printf("/sys/dev/block/%u:%u/queue/%s",
> >>                                  major(st->st_rdev), minor(st->st_rdev),
> >>                                  attribute);
> >> -    ret = g_file_get_contents(sysfspath, val, &len, NULL);
> >> -    if (ret == -1) {
> >> +    if (!g_file_get_contents(sysfspath, val, &len, NULL)) {
> >>          return -ENOENT;
> >>      }
> >>
> >> @@ -1253,7 +1251,7 @@ static int get_sysfs_str_val(struct stat *st, const char *attribute,
> >>      if (*(p + len - 1) == '\n') {
> >>          *(p + len - 1) = '\0';
> >>      }
> >> -    return ret;
> >> +    return 0;
> >>  }
> >>  #endif
> >>
> >
> >
>
diff mbox series

Patch

diff --git a/block/file-posix.c b/block/file-posix.c
index ac1ed54811..0d9d179a35 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1232,7 +1232,6 @@  static int hdev_get_max_hw_transfer(int fd, struct stat *st)
 static int get_sysfs_str_val(struct stat *st, const char *attribute,
                              char **val) {
     g_autofree char *sysfspath = NULL;
-    int ret;
     size_t len;
 
     if (!S_ISBLK(st->st_mode)) {
@@ -1242,8 +1241,7 @@  static int get_sysfs_str_val(struct stat *st, const char *attribute,
     sysfspath = g_strdup_printf("/sys/dev/block/%u:%u/queue/%s",
                                 major(st->st_rdev), minor(st->st_rdev),
                                 attribute);
-    ret = g_file_get_contents(sysfspath, val, &len, NULL);
-    if (ret == -1) {
+    if (!g_file_get_contents(sysfspath, val, &len, NULL)) {
         return -ENOENT;
     }
 
@@ -1253,7 +1251,7 @@  static int get_sysfs_str_val(struct stat *st, const char *attribute,
     if (*(p + len - 1) == '\n') {
         *(p + len - 1) = '\0';
     }
-    return ret;
+    return 0;
 }
 #endif