| Message ID | 20240529113643.3638618-1-oleg.sviridov@red-soft.ru (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | hw/s390x: prevent potential NULL dereference | expand |
Hi Oleg, On 29/5/24 13:36, Oleg Sviridov wrote: > Pointer, returned from function 's390_ipl_get_iplb_pv', may be NULL and is dereferenced immediately after. > > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Signed-off-by: Oleg Sviridov <oleg.sviridov@red-soft.ru> > --- > hw/s390x/ipl.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > index e934bf89d1..2fa6a340a1 100644 > --- a/hw/s390x/ipl.c > +++ b/hw/s390x/ipl.c > @@ -706,9 +706,14 @@ int s390_ipl_prepare_pv_header(Error **errp) > { > IplParameterBlock *ipib = s390_ipl_get_iplb_pv(); > IPLBlockPV *ipib_pv = &ipib->pv; I suppose ipib_pv being NULL here is a bug elsewhere. You should add here: assert(ipib_pv); and look at the backtrace or audit the code. > - void *hdr = g_malloc(ipib_pv->pv_header_len); > + void *hdr; > int rc; > > + if (!ipib_pv) { (If this is a legit error you have to set errp here before returning). > + return -1; > + } > + > + hdr = g_malloc(ipib_pv->pv_header_len); > cpu_physical_memory_read(ipib_pv->pv_header_addr, hdr, > ipib_pv->pv_header_len); > rc = s390_pv_set_sec_parms((uintptr_t)hdr, ipib_pv->pv_header_len, errp); > @@ -722,6 +727,10 @@ int s390_ipl_pv_unpack(void) > IPLBlockPV *ipib_pv = &ipib->pv; > int i, rc = 0; > Ditto assert. > + if (!ipib_pv) { > + return -1; > + } > + > for (i = 0; i < ipib_pv->num_comp; i++) { > rc = s390_pv_unpack(ipib_pv->components[i].addr, > TARGET_PAGE_ALIGN(ipib_pv->components[i].size),
diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c index e934bf89d1..2fa6a340a1 100644 --- a/hw/s390x/ipl.c +++ b/hw/s390x/ipl.c @@ -706,9 +706,14 @@ int s390_ipl_prepare_pv_header(Error **errp) { IplParameterBlock *ipib = s390_ipl_get_iplb_pv(); IPLBlockPV *ipib_pv = &ipib->pv; - void *hdr = g_malloc(ipib_pv->pv_header_len); + void *hdr; int rc; + if (!ipib_pv) { + return -1; + } + + hdr = g_malloc(ipib_pv->pv_header_len); cpu_physical_memory_read(ipib_pv->pv_header_addr, hdr, ipib_pv->pv_header_len); rc = s390_pv_set_sec_parms((uintptr_t)hdr, ipib_pv->pv_header_len, errp); @@ -722,6 +727,10 @@ int s390_ipl_pv_unpack(void) IPLBlockPV *ipib_pv = &ipib->pv; int i, rc = 0; + if (!ipib_pv) { + return -1; + } + for (i = 0; i < ipib_pv->num_comp; i++) { rc = s390_pv_unpack(ipib_pv->components[i].addr, TARGET_PAGE_ALIGN(ipib_pv->components[i].size),
Pointer, returned from function 's390_ipl_get_iplb_pv', may be NULL and is dereferenced immediately after. Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Oleg Sviridov <oleg.sviridov@red-soft.ru> --- hw/s390x/ipl.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)