| Message ID | 20220520165922.2140450-1-keescook@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fs/coda: Do not use partially allocated struct | expand |
Looks good to me. The old code was trying to be too smart for its own good and the type gets lost by the uc_data = (void *) cast anyway. Jan On Fri, May 20, 2022 at 09:59:22AM -0700, Kees Cook wrote: > GCC 12 does not like seeing a partially allocated structure being used, > especially when a pointer is being passed out of function scope. Since > only the struct coda_in_hdr member of union inputArgs is being allocated > and used, just replace union inputArgs with struct coda_in_hdr. > > ../fs/coda/upcall.c: In function 'coda_upcall': > ../fs/coda/upcall.c:801:22: warning: array subscript 'union inputArgs[0]' is partly outside array bounds of 'unsigned char[20]' [-Warray-bounds] > 801 | sig_inputArgs->ih.opcode = CODA_SIGNAL; > | ^~ > In file included from ../include/linux/fs.h:45, > from ../include/linux/huge_mm.h:8, > from ../include/linux/mm.h:700, > from ../fs/coda/upcall.c:22: > In function 'kvmalloc', > inlined from 'kvzalloc' at ../include/linux/slab.h:758:9, > inlined from 'coda_upcall' at ../fs/coda/upcall.c:794:18: > ../include/linux/slab.h:750:16: note: object of size 20 allocated by 'kvmalloc_node' > 750 | return kvmalloc_node(size, flags, NUMA_NO_NODE); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > ../fs/coda/upcall.c: In function 'coda_upcall': > ../fs/coda/upcall.c:802:22: warning: array subscript 'union inputArgs[0]' is partly outside array bounds of 'unsigned char[20]' [-Warray-bounds] > 802 | sig_inputArgs->ih.unique = req->uc_unique; > | ^~ > In function 'kvmalloc', > inlined from 'kvzalloc' at ../include/linux/slab.h:758:9, > inlined from 'coda_upcall' at ../fs/coda/upcall.c:794:18: > ../include/linux/slab.h:750:16: note: object of size 20 allocated by 'kvmalloc_node' > 750 | return kvmalloc_node(size, flags, NUMA_NO_NODE); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Cc: Jan Harkes <jaharkes@cs.cmu.edu> > Cc: coda@cs.cmu.edu > Cc: codalist@coda.cs.cmu.edu > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > fs/coda/upcall.c | 20 ++++++++++---------- > 1 file changed, 10 insertions(+), 10 deletions(-) > > diff --git a/fs/coda/upcall.c b/fs/coda/upcall.c > index 59f6cfd06f96..21e4f5f446b2 100644 > --- a/fs/coda/upcall.c > +++ b/fs/coda/upcall.c > @@ -711,7 +711,7 @@ static int coda_upcall(struct venus_comm *vcp, > union inputArgs *buffer) > { > union outputArgs *out; > - union inputArgs *sig_inputArgs; > + struct coda_in_hdr *ih; > struct upc_req *req = NULL, *sig_req; > int error; > > @@ -791,22 +791,22 @@ static int coda_upcall(struct venus_comm *vcp, > sig_req = kmalloc(sizeof(struct upc_req), GFP_KERNEL); > if (!sig_req) goto exit; > > - sig_inputArgs = kvzalloc(sizeof(struct coda_in_hdr), GFP_KERNEL); > - if (!sig_inputArgs) { > + ih = kvzalloc(sizeof(*ih), GFP_KERNEL); > + if (!ih) { > kfree(sig_req); > goto exit; > } > > error = -EINTR; > - sig_inputArgs->ih.opcode = CODA_SIGNAL; > - sig_inputArgs->ih.unique = req->uc_unique; > + ih->opcode = CODA_SIGNAL; > + ih->unique = req->uc_unique; > > sig_req->uc_flags = CODA_REQ_ASYNC; > - sig_req->uc_opcode = sig_inputArgs->ih.opcode; > - sig_req->uc_unique = sig_inputArgs->ih.unique; > - sig_req->uc_data = (void *)sig_inputArgs; > - sig_req->uc_inSize = sizeof(struct coda_in_hdr); > - sig_req->uc_outSize = sizeof(struct coda_in_hdr); > + sig_req->uc_opcode = ih->opcode; > + sig_req->uc_unique = ih->unique; > + sig_req->uc_data = (void *)ih; > + sig_req->uc_inSize = sizeof(*ih); > + sig_req->uc_outSize = sizeof(*ih); > > /* insert at head of queue! */ > list_add(&(sig_req->uc_chain), &vcp->vc_pending); > -- > 2.32.0 > >
diff --git a/fs/coda/upcall.c b/fs/coda/upcall.c index 59f6cfd06f96..21e4f5f446b2 100644 --- a/fs/coda/upcall.c +++ b/fs/coda/upcall.c @@ -711,7 +711,7 @@ static int coda_upcall(struct venus_comm *vcp, union inputArgs *buffer) { union outputArgs *out; - union inputArgs *sig_inputArgs; + struct coda_in_hdr *ih; struct upc_req *req = NULL, *sig_req; int error; @@ -791,22 +791,22 @@ static int coda_upcall(struct venus_comm *vcp, sig_req = kmalloc(sizeof(struct upc_req), GFP_KERNEL); if (!sig_req) goto exit; - sig_inputArgs = kvzalloc(sizeof(struct coda_in_hdr), GFP_KERNEL); - if (!sig_inputArgs) { + ih = kvzalloc(sizeof(*ih), GFP_KERNEL); + if (!ih) { kfree(sig_req); goto exit; } error = -EINTR; - sig_inputArgs->ih.opcode = CODA_SIGNAL; - sig_inputArgs->ih.unique = req->uc_unique; + ih->opcode = CODA_SIGNAL; + ih->unique = req->uc_unique; sig_req->uc_flags = CODA_REQ_ASYNC; - sig_req->uc_opcode = sig_inputArgs->ih.opcode; - sig_req->uc_unique = sig_inputArgs->ih.unique; - sig_req->uc_data = (void *)sig_inputArgs; - sig_req->uc_inSize = sizeof(struct coda_in_hdr); - sig_req->uc_outSize = sizeof(struct coda_in_hdr); + sig_req->uc_opcode = ih->opcode; + sig_req->uc_unique = ih->unique; + sig_req->uc_data = (void *)ih; + sig_req->uc_inSize = sizeof(*ih); + sig_req->uc_outSize = sizeof(*ih); /* insert at head of queue! */ list_add(&(sig_req->uc_chain), &vcp->vc_pending);
GCC 12 does not like seeing a partially allocated structure being used, especially when a pointer is being passed out of function scope. Since only the struct coda_in_hdr member of union inputArgs is being allocated and used, just replace union inputArgs with struct coda_in_hdr. ../fs/coda/upcall.c: In function 'coda_upcall': ../fs/coda/upcall.c:801:22: warning: array subscript 'union inputArgs[0]' is partly outside array bounds of 'unsigned char[20]' [-Warray-bounds] 801 | sig_inputArgs->ih.opcode = CODA_SIGNAL; | ^~ In file included from ../include/linux/fs.h:45, from ../include/linux/huge_mm.h:8, from ../include/linux/mm.h:700, from ../fs/coda/upcall.c:22: In function 'kvmalloc', inlined from 'kvzalloc' at ../include/linux/slab.h:758:9, inlined from 'coda_upcall' at ../fs/coda/upcall.c:794:18: ../include/linux/slab.h:750:16: note: object of size 20 allocated by 'kvmalloc_node' 750 | return kvmalloc_node(size, flags, NUMA_NO_NODE); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ../fs/coda/upcall.c: In function 'coda_upcall': ../fs/coda/upcall.c:802:22: warning: array subscript 'union inputArgs[0]' is partly outside array bounds of 'unsigned char[20]' [-Warray-bounds] 802 | sig_inputArgs->ih.unique = req->uc_unique; | ^~ In function 'kvmalloc', inlined from 'kvzalloc' at ../include/linux/slab.h:758:9, inlined from 'coda_upcall' at ../fs/coda/upcall.c:794:18: ../include/linux/slab.h:750:16: note: object of size 20 allocated by 'kvmalloc_node' 750 | return kvmalloc_node(size, flags, NUMA_NO_NODE); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Cc: Jan Harkes <jaharkes@cs.cmu.edu> Cc: coda@cs.cmu.edu Cc: codalist@coda.cs.cmu.edu Signed-off-by: Kees Cook <keescook@chromium.org> --- fs/coda/upcall.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-)