| Message ID | 20220614134952.156010-1-ajd@linux.ibm.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | powerpc/rtas: Allow ibm,platform-dump RTAS call with null buffer address | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/github-powerpc_ppctests | success | Successfully ran 10 jobs. |
| snowpatch_ozlabs/github-powerpc_selftests | success | Successfully ran 10 jobs. |
| snowpatch_ozlabs/github-powerpc_sparse | success | Successfully ran 4 jobs. |
| snowpatch_ozlabs/github-powerpc_clang | warning | kernel (mpc885_ads, ubuntu-21.10, ppc64) found 2 issues. |
| snowpatch_ozlabs/github-powerpc_kernel_qemu | warning | kernel (ppc64_defconfig, fedora-34) found 2 issues. |
Andrew Donnellan <ajd@linux.ibm.com> writes: > Add a special case to block_rtas_call() to allow the ibm,platform-dump RTAS > call through the RTAS filter if the buffer address is 0. > > According to PAPR, ibm,platform-dump is called with a null buffer address > to notify the platform firmware that processing of a particular dump is > finished. > > Without this, on a pseries machine with CONFIG_PPC_RTAS_FILTER enabled, an > application such as rtas_errd that is attempting to retrieve a dump will > encounter an error at the end of the retrieval process. > > Fixes: bd59380c5ba4 ("powerpc/rtas: Restrict RTAS requests from userspace") > Cc: stable@vger.kernel.org > Reported-by: Sathvika Vasireddy <sathvika@linux.ibm.com> > Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> I agree this allows ibm,platform-dump to work without weakening the filter for other calls. Thanks. Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
On 6/14/22 06:49, Andrew Donnellan wrote: > Add a special case to block_rtas_call() to allow the ibm,platform-dump RTAS > call through the RTAS filter if the buffer address is 0. > > According to PAPR, ibm,platform-dump is called with a null buffer address > to notify the platform firmware that processing of a particular dump is > finished. > > Without this, on a pseries machine with CONFIG_PPC_RTAS_FILTER enabled, an > application such as rtas_errd that is attempting to retrieve a dump will > encounter an error at the end of the retrieval process. > > Fixes: bd59380c5ba4 ("powerpc/rtas: Restrict RTAS requests from userspace") > Cc: stable@vger.kernel.org > Reported-by: Sathvika Vasireddy <sathvika@linux.ibm.com> > Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Similar to what is done for ibm,configure-connector with idx_buf2 and a NULL address. Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com> > --- > arch/powerpc/kernel/rtas.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c > index a6fce3106e02..693133972294 100644 > --- a/arch/powerpc/kernel/rtas.c > +++ b/arch/powerpc/kernel/rtas.c > @@ -1071,7 +1071,7 @@ static struct rtas_filter rtas_filters[] __ro_after_init = { > { "get-time-of-day", -1, -1, -1, -1, -1 }, > { "ibm,get-vpd", -1, 0, -1, 1, 2 }, > { "ibm,lpar-perftools", -1, 2, 3, -1, -1 }, > - { "ibm,platform-dump", -1, 4, 5, -1, -1 }, > + { "ibm,platform-dump", -1, 4, 5, -1, -1 }, /* Special cased */ > { "ibm,read-slot-reset-state", -1, -1, -1, -1, -1 }, > { "ibm,scan-log-dump", -1, 0, 1, -1, -1 }, > { "ibm,set-dynamic-indicator", -1, 2, -1, -1, -1 }, > @@ -1120,6 +1120,15 @@ static bool block_rtas_call(int token, int nargs, > size = 1; > > end = base + size - 1; > + > + /* > + * Special case for ibm,platform-dump - NULL buffer > + * address is used to indicate end of dump processing > + */ > + if (!strcmp(f->name, "ibm,platform-dump") && > + base == 0) > + return false; > + > if (!in_rmo_buf(base, end)) > goto err; > }
On Tue, 14 Jun 2022 23:49:52 +1000, Andrew Donnellan wrote: > Add a special case to block_rtas_call() to allow the ibm,platform-dump RTAS > call through the RTAS filter if the buffer address is 0. > > According to PAPR, ibm,platform-dump is called with a null buffer address > to notify the platform firmware that processing of a particular dump is > finished. > > [...] Applied to powerpc/fixes. [1/1] powerpc/rtas: Allow ibm,platform-dump RTAS call with null buffer address https://git.kernel.org/powerpc/c/7bc08056a6dabc3a1442216daf527edf61ac24b6 cheers
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c index a6fce3106e02..693133972294 100644 --- a/arch/powerpc/kernel/rtas.c +++ b/arch/powerpc/kernel/rtas.c @@ -1071,7 +1071,7 @@ static struct rtas_filter rtas_filters[] __ro_after_init = { { "get-time-of-day", -1, -1, -1, -1, -1 }, { "ibm,get-vpd", -1, 0, -1, 1, 2 }, { "ibm,lpar-perftools", -1, 2, 3, -1, -1 }, - { "ibm,platform-dump", -1, 4, 5, -1, -1 }, + { "ibm,platform-dump", -1, 4, 5, -1, -1 }, /* Special cased */ { "ibm,read-slot-reset-state", -1, -1, -1, -1, -1 }, { "ibm,scan-log-dump", -1, 0, 1, -1, -1 }, { "ibm,set-dynamic-indicator", -1, 2, -1, -1, -1 }, @@ -1120,6 +1120,15 @@ static bool block_rtas_call(int token, int nargs, size = 1; end = base + size - 1; + + /* + * Special case for ibm,platform-dump - NULL buffer + * address is used to indicate end of dump processing + */ + if (!strcmp(f->name, "ibm,platform-dump") && + base == 0) + return false; + if (!in_rmo_buf(base, end)) goto err; }
Add a special case to block_rtas_call() to allow the ibm,platform-dump RTAS call through the RTAS filter if the buffer address is 0. According to PAPR, ibm,platform-dump is called with a null buffer address to notify the platform firmware that processing of a particular dump is finished. Without this, on a pseries machine with CONFIG_PPC_RTAS_FILTER enabled, an application such as rtas_errd that is attempting to retrieve a dump will encounter an error at the end of the retrieval process. Fixes: bd59380c5ba4 ("powerpc/rtas: Restrict RTAS requests from userspace") Cc: stable@vger.kernel.org Reported-by: Sathvika Vasireddy <sathvika@linux.ibm.com> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> --- arch/powerpc/kernel/rtas.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)