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Groups > linux.kernel > #1491552
| From | Paul Bolle <pebolle@tiscali.nl> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH 4/5] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure |
| Date | 2016-09-26 23:20 +0200 |
| Message-ID | <slLtE-wZ-9@gated-at.bofh.it> (permalink) |
| References | <qEuGl-43C-5@gated-at.bofh.it> <slGaB-5yk-1@gated-at.bofh.it> <slGki-5BO-17@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
Markus,
On Mon, 2016-09-26 at 17:43 +0200, SF Markus Elfring wrote:
> Memory was not released (as it would be expected) when one call
> of further resource reservations failed.
This was the only thing in this series that triggered more than a, very
uninspired, "meh" on first read.
> * Split a condition check for memory allocation failures so that
> each pointer from these function calls will be checked immediately.
>
> See also background information:
> Topic "CWE-754: Improper check for unusual or exceptional conditions"
> Link: https://cwe.mitre.org/data/definitions/754.html
A quick scan of that link suggests we can do without the above
"background information" in the commit explanation.
> * Adjust jump targets according to the Linux coding style convention.
Another "meh".
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
> drivers/isdn/gigaset/common.c | 20 ++++++++++++--------
> 1 file changed, 12 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/isdn/gigaset/common.c
> b/drivers/isdn/gigaset/common.c
> index c05a2a4..2e9382f 100644
> --- a/drivers/isdn/gigaset/common.c
> +++ b/drivers/isdn/gigaset/common.c
> @@ -710,10 +710,13 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
> cs->mode = M_UNKNOWN;
> cs->mstate = MS_UNINITIALIZED;
> cs->bcs = kmalloc_array(channels, sizeof(*cs->bcs), GFP_KERNEL);
> + if (!cs->bcs)
> + goto report_failure;
> +
> cs->inbuf = kmalloc(sizeof(*cs->inbuf), GFP_KERNEL);
> - if (!cs->bcs || !cs->inbuf) {
> - goto error;
> - }
> + if (!cs->inbuf)
> + goto free_bcs;
> +
> ++cs->cs_init;
>
> gig_dbg(DEBUG_INIT, "setting up at_state");
> @@ -737,14 +740,14 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
> gig_dbg(DEBUG_INIT, "setting up iif");
> if (gigaset_isdn_regdev(cs, modulename) < 0) {
> pr_err("error registering ISDN device\n");
> - goto error;
> + goto free_bcs;
> }
>
> make_valid(cs, VALID_ID);
> ++cs->cs_init;
> gig_dbg(DEBUG_INIT, "setting up hw");
> if (cs->ops->initcshw(cs) < 0)
> - goto error;
> + goto free_bcs;
>
> ++cs->cs_init;
>
> @@ -759,7 +762,7 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
> gig_dbg(DEBUG_INIT, "setting up bcs[%d]", i);
> if (gigaset_initbcs(cs->bcs + i, cs, i) < 0) {
> pr_err("could not allocate channel %d data\n", i);
> - goto error;
> + goto free_bcs;
> }
> }
>
> @@ -772,8 +775,9 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
>
> gig_dbg(DEBUG_INIT, "cs initialized");
> return cs;
> -
> -error:
> +free_bcs:
> + kfree(cs->bcs);
> +report_failure:
> gig_dbg(DEBUG_INIT, "failed");
> gigaset_freecs(cs);
gigaset_freecs() is not a function I look at for the fun of it. But
still, in it we find:
case 0: /* error in basic setup */
[...]
kfree(cs->inbuf);
kfree(cs->bcs);
As far as I can tell we will call those two kfree()'s if we jump to
"error". So, contrary to your analysis, I don't think we leak cs->bcs.
> return NULL;
Paul Bolle
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[PATCH 0/5] ISDN-Gigaset: Fine-tuning for three function implementations SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 17:40 +0200
[PATCH 1/5] ISDN-Gigaset: Use kmalloc_array() in two functions SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 17:40 +0200
Re: [PATCH 1/5] ISDN-Gigaset: Use kmalloc_array() in two functions Paul Bolle <pebolle@tiscali.nl> - 2016-09-28 13:40 +0200
Re: [PATCH 1/5] ISDN-Gigaset: Use kmalloc_array() in two functions SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-28 18:50 +0200
Re: [PATCH 1/5] ISDN-Gigaset: Use kmalloc_array() in two functions Paul Bolle <pebolle@tiscali.nl> - 2016-09-28 19:50 +0200
[PATCH 2/5] ISDN-Gigaset: Improve another size determination in gigaset_initcs() SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 17:50 +0200
[PATCH 4/5] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 17:50 +0200
Re: [PATCH 4/5] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure Paul Bolle <pebolle@tiscali.nl> - 2016-09-26 23:20 +0200
Re: ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-27 07:30 +0200
Re: ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure Paul Bolle <pebolle@tiscali.nl> - 2016-09-27 10:50 +0200
Re: ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-27 11:40 +0200
Re: ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure Paul Bolle <pebolle@tiscali.nl> - 2016-09-27 11:50 +0200
Re: [Gigaset307x-common] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure Tilman Schmidt <tilman@imap.cc> - 2016-09-27 12:30 +0200
Re: [Gigaset307x-common] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-27 13:40 +0200
Re: [Gigaset307x-common] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure Tilman Schmidt <tilman@imap.cc> - 2016-09-27 14:10 +0200
Re: [Gigaset307x-common] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure isdn@linux-pingi.de - 2016-09-27 14:20 +0200
Re: [Gigaset307x-common] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-27 15:00 +0200
Re: [Gigaset307x-common] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure Tilman Schmidt <tilman@imap.cc> - 2016-09-27 16:40 +0200
Re: [PATCH 4/5] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure Dan Carpenter <dan.carpenter@oracle.com> - 2016-09-27 09:40 +0200
Re: [PATCH 4/5] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-27 17:20 +0200
Re: [PATCH 4/5] ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure Dan Carpenter <dan.carpenter@oracle.com> - 2016-09-27 09:20 +0200
Re: ISDN-Gigaset: Release memory in gigaset_initcs() after an allocation failure SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-27 09:30 +0200
[PATCH 3/5] ISDN-Gigaset: Delete an error message for a failed memory allocation SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 17:50 +0200
Re: [PATCH 3/5] ISDN-Gigaset: Delete an error message for a failed memory allocation Tilman Schmidt <tilman@imap.cc> - 2016-09-27 13:00 +0200
Re: [PATCH 3/5] ISDN-Gigaset: Delete an error message for a failed memory allocation Paul Bolle <pebolle@tiscali.nl> - 2016-09-28 13:50 +0200
[PATCH 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 17:50 +0200
RE: [PATCH 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses David Laight <David.Laight@ACULAB.COM> - 2016-09-26 18:10 +0200
Re: [PATCH 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses Joe Perches <joe@perches.com> - 2016-09-26 18:30 +0200
Re: [PATCH 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 18:50 +0200
Re: [PATCH 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses Julia Lawall <julia.lawall@lip6.fr> - 2016-09-26 19:00 +0200
[PATCH v2 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 19:50 +0200
Re: [PATCH v2 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses Paul Bolle <pebolle@tiscali.nl> - 2016-09-26 20:40 +0200
Re: [PATCH v2 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 20:50 +0200
Re: [PATCH v2 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses David Miller <davem@davemloft.net> - 2016-09-27 02:20 +0200
Re: [PATCH v2 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-27 07:40 +0200
Re: [PATCH 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> - 2016-09-26 19:40 +0200
Re: ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-26 20:10 +0200
Re: ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses Paul Bolle <pebolle@tiscali.nl> - 2016-09-26 20:40 +0200
Re: [PATCH 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses Dan Carpenter <dan.carpenter@oracle.com> - 2016-09-27 09:10 +0200
Re: [PATCH 5/5] ISDN-Gigaset: Enclose two expressions for the sizeof operator by parentheses Dan Carpenter <dan.carpenter@oracle.com> - 2016-09-27 09:30 +0200
Re: [PATCH 0/5] ISDN-Gigaset: Fine-tuning for three function implementations Paul Bolle <pebolle@tiscali.nl> - 2016-09-26 22:40 +0200
Re: ISDN-Gigaset: Fine-tuning for three function implementations SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-27 07:20 +0200
Re: [PATCH 0/5] ISDN-Gigaset: Fine-tuning for three function implementations Paul Bolle <pebolle@tiscali.nl> - 2016-09-28 14:00 +0200
Re: ISDN-Gigaset: Fine-tuning for three function implementations SF Markus Elfring <elfring@users.sourceforge.net> - 2016-09-28 19:00 +0200
Re: ISDN-Gigaset: Fine-tuning for three function implementations Paul Bolle <pebolle@tiscali.nl> - 2016-09-28 20:00 +0200
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