| Message ID | 20230615025312.48712-1-jiasheng@iscas.ac.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] pstore/platform: Add check for kstrdup | expand |
On Thu, Jun 15, 2023 at 10:53:12AM +0800, Jiasheng Jiang wrote: > Add check for the return value of kstrdup() and return the error > if it fails in order to avoid NULL pointer dereference. > > Fixes: 563ca40ddf40 ("pstore/platform: Switch pstore_info::name to const") > Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn> Thanks, this is looking better! > --- > Changelog: > > v1 -> v2: > > 1. Allocate a copy earlier. > --- > fs/pstore/platform.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c > index cbc0b468c1ab..727f8ce71062 100644 > --- a/fs/pstore/platform.c > +++ b/fs/pstore/platform.c > @@ -573,6 +573,8 @@ static int pstore_write_user_compat(struct pstore_record *record, > */ > int pstore_register(struct pstore_info *psi) > { > + char *new_backend; > + > if (backend && strcmp(backend, psi->name)) { > pr_warn("backend '%s' already in use: ignoring '%s'\n", > backend, psi->name); > @@ -593,6 +595,10 @@ int pstore_register(struct pstore_info *psi) > return -EINVAL; > } > > + new_backend = kstrdup(psi->name, GFP_KERNEL); > + if (!new_backend) > + return -ENOMEM; > + > mutex_lock(&psinfo_lock); > if (psinfo) { > pr_warn("backend '%s' already loaded: ignoring '%s'\n", In my suggestion I had included a kfree() for new_backend in this above error path, which is missing here. Can you respin it with that added? > @@ -630,7 +636,7 @@ int pstore_register(struct pstore_info *psi) > * Update the module parameter backend, so it is visible > * through /sys/module/pstore/parameters/backend > */ > - backend = kstrdup(psi->name, GFP_KERNEL); > + backend = new_backend; > > pr_info("Registered %s as persistent store backend\n", psi->name); > > -- > 2.25.1 > But otherwise, yeah, looks good. Thanks!
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index cbc0b468c1ab..727f8ce71062 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -573,6 +573,8 @@ static int pstore_write_user_compat(struct pstore_record *record, */ int pstore_register(struct pstore_info *psi) { + char *new_backend; + if (backend && strcmp(backend, psi->name)) { pr_warn("backend '%s' already in use: ignoring '%s'\n", backend, psi->name); @@ -593,6 +595,10 @@ int pstore_register(struct pstore_info *psi) return -EINVAL; } + new_backend = kstrdup(psi->name, GFP_KERNEL); + if (!new_backend) + return -ENOMEM; + mutex_lock(&psinfo_lock); if (psinfo) { pr_warn("backend '%s' already loaded: ignoring '%s'\n", @@ -630,7 +636,7 @@ int pstore_register(struct pstore_info *psi) * Update the module parameter backend, so it is visible * through /sys/module/pstore/parameters/backend */ - backend = kstrdup(psi->name, GFP_KERNEL); + backend = new_backend; pr_info("Registered %s as persistent store backend\n", psi->name);
Add check for the return value of kstrdup() and return the error if it fails in order to avoid NULL pointer dereference. Fixes: 563ca40ddf40 ("pstore/platform: Switch pstore_info::name to const") Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn> --- Changelog: v1 -> v2: 1. Allocate a copy earlier. --- fs/pstore/platform.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)