| Message ID | 20230524164210.20567-1-osmtendev@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | smsdvb-debugfs.c: Fix error checking for debugfs_create_file | expand |
Em Wed, 24 May 2023 21:42:10 +0500 Osama Muhammad <osmtendev@gmail.com> escreveu: > This patch fixes the error checking in smsdvb-debugfs.c in > debugfs_create_file. The correct way to check if an error occurred > is using 'IS_ERR_OR_NULL' inline function. > > Signed-off-by: Osama Muhammad <osmtendev@gmail.com> > --- > drivers/media/common/siano/smsdvb-debugfs.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/media/common/siano/smsdvb-debugfs.c b/drivers/media/common/siano/smsdvb-debugfs.c > index 8916bb644756..0f8750d7993c 100644 > --- a/drivers/media/common/siano/smsdvb-debugfs.c > +++ b/drivers/media/common/siano/smsdvb-debugfs.c > @@ -469,7 +469,7 @@ int smsdvb_debugfs_create(struct smsdvb_client_t *client) > > d = debugfs_create_file("stats", S_IRUGO | S_IWUSR, client->debugfs, > client, &debugfs_stats_ops); > - if (!d) { > + if (IS_ERR_OR_NULL(d)) { > debugfs_remove(client->debugfs); > return -ENOMEM; if IS_ERR, it is probably better to return PTR_ERR(d). So, please change it accordingly, returning -ENOMEM only on NULL, e. g. something like (untested): if (IS_ERR_OR_NULL(d)) { debugfs_remove(client->debugfs); if (!d) return -ENOMEM; return PTR_ERR(d); } Regards, Mauro
Hi, After researching more into it I have come to know that the debugfs API will not return null on error but an ERR_PTR. The modern wisdom about it is to ignore the errors returned by the function as stated in the comment above the function debugfs_create_file. > * NOTE: it's expected that most callers should _ignore_ the errors returned >* by this function. Other debugfs functions handle the fact that the "dentry" >* passed to them could be an error and they don't crash in that case. > * Drivers should generally work fine even if debugfs fails to init anyway. Here is the link to comment :- https://elixir.bootlin.com/linux/latest/source/fs/debugfs/inode.c#L451 Considering this, I will send the revision of the patch by removing error checks. Please correct me if there are any concerns with this. Thanks, Osmten On Fri, 26 May 2023 at 15:53, Mauro Carvalho Chehab <mchehab@kernel.org> wrote: > > Em Wed, 24 May 2023 21:42:10 +0500 > Osama Muhammad <osmtendev@gmail.com> escreveu: > > > This patch fixes the error checking in smsdvb-debugfs.c in > > debugfs_create_file. The correct way to check if an error occurred > > is using 'IS_ERR_OR_NULL' inline function. > > > > Signed-off-by: Osama Muhammad <osmtendev@gmail.com> > > --- > > drivers/media/common/siano/smsdvb-debugfs.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/media/common/siano/smsdvb-debugfs.c b/drivers/media/common/siano/smsdvb-debugfs.c > > index 8916bb644756..0f8750d7993c 100644 > > --- a/drivers/media/common/siano/smsdvb-debugfs.c > > +++ b/drivers/media/common/siano/smsdvb-debugfs.c > > @@ -469,7 +469,7 @@ int smsdvb_debugfs_create(struct smsdvb_client_t *client) > > > > d = debugfs_create_file("stats", S_IRUGO | S_IWUSR, client->debugfs, > > client, &debugfs_stats_ops); > > - if (!d) { > > + if (IS_ERR_OR_NULL(d)) { > > debugfs_remove(client->debugfs); > > return -ENOMEM; > > if IS_ERR, it is probably better to return PTR_ERR(d). > > So, please change it accordingly, returning -ENOMEM only on NULL, e. g. > something like (untested): > > if (IS_ERR_OR_NULL(d)) { > debugfs_remove(client->debugfs); > if (!d) > return -ENOMEM; > return PTR_ERR(d); > } > > Regards, > Mauro
diff --git a/drivers/media/common/siano/smsdvb-debugfs.c b/drivers/media/common/siano/smsdvb-debugfs.c index 8916bb644756..0f8750d7993c 100644 --- a/drivers/media/common/siano/smsdvb-debugfs.c +++ b/drivers/media/common/siano/smsdvb-debugfs.c @@ -469,7 +469,7 @@ int smsdvb_debugfs_create(struct smsdvb_client_t *client) d = debugfs_create_file("stats", S_IRUGO | S_IWUSR, client->debugfs, client, &debugfs_stats_ops); - if (!d) { + if (IS_ERR_OR_NULL(d)) { debugfs_remove(client->debugfs); return -ENOMEM; }
This patch fixes the error checking in smsdvb-debugfs.c in debugfs_create_file. The correct way to check if an error occurred is using 'IS_ERR_OR_NULL' inline function. Signed-off-by: Osama Muhammad <osmtendev@gmail.com> --- drivers/media/common/siano/smsdvb-debugfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)