drivers/dma-buf/dma-buf.c | 49 ++++++++++++++++++++++++--------------- 1 file changed, 30 insertions(+), 19 deletions(-)
dma_buf_show_fdinfo functions into a single function
that prints size, count, flags, attachments, mappings, exp_name, and
name safely with proper spinlock protection for name access.
Signed-off-by: Biancaa Ramesh <biancaa2210329@ssn.edu.in>
---
drivers/dma-buf/dma-buf.c | 49 ++++++++++++++++++++++++---------------
1 file changed, 30 insertions(+), 19 deletions(-)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 2bcf9ceca997..1c0035601c4f 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -394,17 +394,21 @@ static __poll_t dma_buf_poll(struct file *file, poll_table *poll)
*/
static long dma_buf_set_name(struct dma_buf *dmabuf, const char __user *buf)
{
- char *name = strndup_user(buf, DMA_BUF_NAME_LEN);
+ char *name;
- if (IS_ERR(name))
- return PTR_ERR(name);
+ if (!buf)
+ return -EINVAL;
- spin_lock(&dmabuf->name_lock);
- kfree(dmabuf->name);
- dmabuf->name = name;
- spin_unlock(&dmabuf->name_lock);
+ name = strndup_user(buf, DMA_BUF_NAME_LEN);
+ if (IS_ERR(name))
+ return PTR_ERR(name);
- return 0;
+ spin_lock(&dmabuf->name_lock);
+ kfree(dmabuf->name);
+ dmabuf->name = name;
+ spin_unlock(&dmabuf->name_lock);
+
+ return 0;
}
#if IS_ENABLED(CONFIG_SYNC_FILE)
@@ -567,20 +571,27 @@ static long dma_buf_ioctl(struct file *file,
}
}
-static void dma_buf_show_fdinfo(struct seq_file *m, struct file *file)
+static void dma_buf_show_fdinfo(struct seq_file *s, struct file *f)
{
- struct dma_buf *dmabuf = file->private_data;
-
- seq_printf(m, "size:\t%zu\n", dmabuf->size);
- /* Don't count the temporary reference taken inside procfs seq_show */
- seq_printf(m, "count:\t%ld\n", file_count(dmabuf->file) - 1);
- seq_printf(m, "exp_name:\t%s\n", dmabuf->exp_name);
- spin_lock(&dmabuf->name_lock);
- if (dmabuf->name)
- seq_printf(m, "name:\t%s\n", dmabuf->name);
- spin_unlock(&dmabuf->name_lock);
+ struct dma_buf *dmabuf = f->private_data;
+
+ if (!dmabuf)
+ return;
+
+ seq_printf(s, "flags:\t%lu\n", f->f_flags);
+ seq_printf(s, "size:\t%llu\n", dmabuf->size);
+ seq_printf(s, "count:\t%ld\n", file_count(dmabuf->file) - 1);
+ seq_printf(s, "attachments:\t%d\n", atomic_read(&dmabuf->num_attachments));
+ seq_printf(s, "mappings:\t%d\n", atomic_read(&dmabuf->num_mappings));
+ seq_printf(s, "exp_name:\t%s\n", dmabuf->exp_name ? dmabuf->exp_name : "N/A");
+
+ spin_lock(&dmabuf->name_lock);
+ if (dmabuf->name)
+ seq_printf(s, "name:\t%s\n", dmabuf->name);
+ spin_unlock(&dmabuf->name_lock);
}
+
static const struct file_operations dma_buf_fops = {
.release = dma_buf_file_release,
.mmap = dma_buf_mmap_internal,
--
2.43.0
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ssn.edu.in <http://www.ssn.edu.in/>Hi Biancaa,
kernel test robot noticed the following build errors:
[auto build test ERROR on linus/master]
[also build test ERROR on v6.18-rc2 next-20251021]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Biancaa-Ramesh/dma-buf-improve-dma_buf_show_fdinfo-output/20251021-213541
base: linus/master
patch link: https://lore.kernel.org/r/20251021133132.29751-1-biancaa2210329%40ssn.edu.in
patch subject: [PATCH] dma-buf: improve dma_buf_show_fdinfo output
config: x86_64-buildonly-randconfig-002-20251022 (https://download.01.org/0day-ci/archive/20251022/202510221000.gUhf7ABH-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251022/202510221000.gUhf7ABH-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510221000.gUhf7ABH-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/dma-buf/dma-buf.c: In function 'dma_buf_show_fdinfo':
drivers/dma-buf/dma-buf.c:581:30: warning: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'unsigned int' [-Wformat=]
581 | seq_printf(s, "flags:\t%lu\n", f->f_flags);
| ~~^ ~~~~~~~~~~
| | |
| | unsigned int
| long unsigned int
| %u
drivers/dma-buf/dma-buf.c:582:30: warning: format '%llu' expects argument of type 'long long unsigned int', but argument 3 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
582 | seq_printf(s, "size:\t%llu\n", dmabuf->size);
| ~~~^ ~~~~~~~~~~~~
| | |
| | size_t {aka long unsigned int}
| long long unsigned int
| %lu
>> drivers/dma-buf/dma-buf.c:584:62: error: 'struct dma_buf' has no member named 'num_attachments'; did you mean 'attachments'?
584 | seq_printf(s, "attachments:\t%d\n", atomic_read(&dmabuf->num_attachments));
| ^~~~~~~~~~~~~~~
| attachments
>> drivers/dma-buf/dma-buf.c:585:57: error: 'struct dma_buf' has no member named 'num_mappings'
585 | seq_printf(s, "mappings:\t%d\n", atomic_read(&dmabuf->num_mappings));
| ^~
vim +584 drivers/dma-buf/dma-buf.c
573
574 static void dma_buf_show_fdinfo(struct seq_file *s, struct file *f)
575 {
576 struct dma_buf *dmabuf = f->private_data;
577
578 if (!dmabuf)
579 return;
580
581 seq_printf(s, "flags:\t%lu\n", f->f_flags);
> 582 seq_printf(s, "size:\t%llu\n", dmabuf->size);
583 seq_printf(s, "count:\t%ld\n", file_count(dmabuf->file) - 1);
> 584 seq_printf(s, "attachments:\t%d\n", atomic_read(&dmabuf->num_attachments));
> 585 seq_printf(s, "mappings:\t%d\n", atomic_read(&dmabuf->num_mappings));
586 seq_printf(s, "exp_name:\t%s\n", dmabuf->exp_name ? dmabuf->exp_name : "N/A");
587
588 spin_lock(&dmabuf->name_lock);
589 if (dmabuf->name)
590 seq_printf(s, "name:\t%s\n", dmabuf->name);
591 spin_unlock(&dmabuf->name_lock);
592 }
593
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Biancaa,
kernel test robot noticed the following build warnings:
[auto build test WARNING on linus/master]
[also build test WARNING on v6.18-rc2 next-20251021]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Biancaa-Ramesh/dma-buf-improve-dma_buf_show_fdinfo-output/20251021-213541
base: linus/master
patch link: https://lore.kernel.org/r/20251021133132.29751-1-biancaa2210329%40ssn.edu.in
patch subject: [PATCH] dma-buf: improve dma_buf_show_fdinfo output
config: x86_64-randconfig-002-20251022 (https://download.01.org/0day-ci/archive/20251022/202510220948.fae9xJYg-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251022/202510220948.fae9xJYg-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510220948.fae9xJYg-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/dma-buf/dma-buf.c:581:36: warning: format specifies type 'unsigned long' but the argument has type 'unsigned int' [-Wformat]
581 | seq_printf(s, "flags:\t%lu\n", f->f_flags);
| ~~~ ^~~~~~~~~~
| %u
>> drivers/dma-buf/dma-buf.c:582:36: warning: format specifies type 'unsigned long long' but the argument has type 'size_t' (aka 'unsigned long') [-Wformat]
582 | seq_printf(s, "size:\t%llu\n", dmabuf->size);
| ~~~~ ^~~~~~~~~~~~
| %zu
drivers/dma-buf/dma-buf.c:584:62: error: no member named 'num_attachments' in 'struct dma_buf'; did you mean 'attachments'?
584 | seq_printf(s, "attachments:\t%d\n", atomic_read(&dmabuf->num_attachments));
| ^~~~~~~~~~~~~~~
| attachments
include/linux/dma-buf.h:315:19: note: 'attachments' declared here
315 | struct list_head attachments;
| ^
drivers/dma-buf/dma-buf.c:585:59: error: no member named 'num_mappings' in 'struct dma_buf'
585 | seq_printf(s, "mappings:\t%d\n", atomic_read(&dmabuf->num_mappings));
| ~~~~~~ ^
2 warnings and 2 errors generated.
vim +581 drivers/dma-buf/dma-buf.c
573
574 static void dma_buf_show_fdinfo(struct seq_file *s, struct file *f)
575 {
576 struct dma_buf *dmabuf = f->private_data;
577
578 if (!dmabuf)
579 return;
580
> 581 seq_printf(s, "flags:\t%lu\n", f->f_flags);
> 582 seq_printf(s, "size:\t%llu\n", dmabuf->size);
583 seq_printf(s, "count:\t%ld\n", file_count(dmabuf->file) - 1);
584 seq_printf(s, "attachments:\t%d\n", atomic_read(&dmabuf->num_attachments));
585 seq_printf(s, "mappings:\t%d\n", atomic_read(&dmabuf->num_mappings));
586 seq_printf(s, "exp_name:\t%s\n", dmabuf->exp_name ? dmabuf->exp_name : "N/A");
587
588 spin_lock(&dmabuf->name_lock);
589 if (dmabuf->name)
590 seq_printf(s, "name:\t%s\n", dmabuf->name);
591 spin_unlock(&dmabuf->name_lock);
592 }
593
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Biancaa,
kernel test robot noticed the following build warnings:
[auto build test WARNING on linus/master]
[also build test WARNING on v6.18-rc2 next-20251021]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Biancaa-Ramesh/dma-buf-improve-dma_buf_show_fdinfo-output/20251021-213541
base: linus/master
patch link: https://lore.kernel.org/r/20251021133132.29751-1-biancaa2210329%40ssn.edu.in
patch subject: [PATCH] dma-buf: improve dma_buf_show_fdinfo output
config: x86_64-buildonly-randconfig-002-20251022 (https://download.01.org/0day-ci/archive/20251022/202510220802.svbgdYsJ-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251022/202510220802.svbgdYsJ-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510220802.svbgdYsJ-lkp@intel.com/
All warnings (new ones prefixed by >>):
drivers/dma-buf/dma-buf.c: In function 'dma_buf_show_fdinfo':
>> drivers/dma-buf/dma-buf.c:581:30: warning: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'unsigned int' [-Wformat=]
581 | seq_printf(s, "flags:\t%lu\n", f->f_flags);
| ~~^ ~~~~~~~~~~
| | |
| | unsigned int
| long unsigned int
| %u
>> drivers/dma-buf/dma-buf.c:582:30: warning: format '%llu' expects argument of type 'long long unsigned int', but argument 3 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
582 | seq_printf(s, "size:\t%llu\n", dmabuf->size);
| ~~~^ ~~~~~~~~~~~~
| | |
| | size_t {aka long unsigned int}
| long long unsigned int
| %lu
drivers/dma-buf/dma-buf.c:584:62: error: 'struct dma_buf' has no member named 'num_attachments'; did you mean 'attachments'?
584 | seq_printf(s, "attachments:\t%d\n", atomic_read(&dmabuf->num_attachments));
| ^~~~~~~~~~~~~~~
| attachments
drivers/dma-buf/dma-buf.c:585:57: error: 'struct dma_buf' has no member named 'num_mappings'
585 | seq_printf(s, "mappings:\t%d\n", atomic_read(&dmabuf->num_mappings));
| ^~
vim +581 drivers/dma-buf/dma-buf.c
573
574 static void dma_buf_show_fdinfo(struct seq_file *s, struct file *f)
575 {
576 struct dma_buf *dmabuf = f->private_data;
577
578 if (!dmabuf)
579 return;
580
> 581 seq_printf(s, "flags:\t%lu\n", f->f_flags);
> 582 seq_printf(s, "size:\t%llu\n", dmabuf->size);
583 seq_printf(s, "count:\t%ld\n", file_count(dmabuf->file) - 1);
584 seq_printf(s, "attachments:\t%d\n", atomic_read(&dmabuf->num_attachments));
585 seq_printf(s, "mappings:\t%d\n", atomic_read(&dmabuf->num_mappings));
586 seq_printf(s, "exp_name:\t%s\n", dmabuf->exp_name ? dmabuf->exp_name : "N/A");
587
588 spin_lock(&dmabuf->name_lock);
589 if (dmabuf->name)
590 seq_printf(s, "name:\t%s\n", dmabuf->name);
591 spin_unlock(&dmabuf->name_lock);
592 }
593
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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