pstore/ram: Set freed addresses to NULL

For good measure, set all the freed addresses to NULL when managing
przs.

Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-and-tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Link: https://lore.kernel.org/r/20221011200112.731334-5-keescook@chromium.org
This commit is contained in:
Kees Cook 2022-10-11 13:01:11 -07:00
parent 8bd4da0f06
commit 06b4e09aab
3 changed files with 18 additions and 8 deletions

View File

@ -453,25 +453,27 @@ static void ramoops_free_przs(struct ramoops_context *cxt)
int i;
/* Free pmsg PRZ */
persistent_ram_free(cxt->mprz);
persistent_ram_free(&cxt->mprz);
/* Free console PRZ */
persistent_ram_free(cxt->cprz);
persistent_ram_free(&cxt->cprz);
/* Free dump PRZs */
if (cxt->dprzs) {
for (i = 0; i < cxt->max_dump_cnt; i++)
persistent_ram_free(cxt->dprzs[i]);
persistent_ram_free(&cxt->dprzs[i]);
kfree(cxt->dprzs);
cxt->dprzs = NULL;
cxt->max_dump_cnt = 0;
}
/* Free ftrace PRZs */
if (cxt->fprzs) {
for (i = 0; i < cxt->max_ftrace_cnt; i++)
persistent_ram_free(cxt->fprzs[i]);
persistent_ram_free(&cxt->fprzs[i]);
kfree(cxt->fprzs);
cxt->fprzs = NULL;
cxt->max_ftrace_cnt = 0;
}
}
@ -555,9 +557,10 @@ static int ramoops_init_przs(const char *name,
while (i > 0) {
i--;
persistent_ram_free(prz_ar[i]);
persistent_ram_free(&prz_ar[i]);
}
kfree(prz_ar);
prz_ar = NULL;
goto fail;
}
*paddr += zone_sz;

View File

@ -544,8 +544,14 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig,
return 0;
}
void persistent_ram_free(struct persistent_ram_zone *prz)
void persistent_ram_free(struct persistent_ram_zone **_prz)
{
struct persistent_ram_zone *prz;
if (!_prz)
return;
prz = *_prz;
if (!prz)
return;
@ -569,6 +575,7 @@ void persistent_ram_free(struct persistent_ram_zone *prz)
persistent_ram_free_old(prz);
kfree(prz->label);
kfree(prz);
*_prz = NULL;
}
struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size,
@ -605,6 +612,6 @@ struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size,
return prz;
err:
persistent_ram_free(prz);
persistent_ram_free(&prz);
return ERR_PTR(ret);
}

View File

@ -82,7 +82,7 @@ struct persistent_ram_zone {
struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size,
u32 sig, struct persistent_ram_ecc_info *ecc_info,
unsigned int memtype, u32 flags, char *label);
void persistent_ram_free(struct persistent_ram_zone *prz);
void persistent_ram_free(struct persistent_ram_zone **_prz);
void persistent_ram_zap(struct persistent_ram_zone *prz);
int persistent_ram_write(struct persistent_ram_zone *prz, const void *s,