nfp: validate rtsym accesses fall within the symbol
authorJakub Kicinski <jakub.kicinski@netronome.com>
Tue, 4 Sep 2018 14:37:33 +0000 (07:37 -0700)
committerDavid S. Miller <davem@davemloft.net>
Thu, 6 Sep 2018 05:17:07 +0000 (22:17 -0700)
With the accesses to rtsyms now all going via special helpers
we can easily make sure the driver is not reading past the
end of the symbol.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Francois H. Theron <francois.theron@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/netronome/nfp/nfpcore/nfp_rtsym.c

index 5e416e14e46ac5c94202697cce70ac150e0f67b0..1ad0a015572e557e9721c7764e14f25f0e233082 100644 (file)
@@ -39,6 +39,8 @@
  *          Espen Skoglund <espen.skoglund@netronome.com>
  *          Francois H. Theron <francois.theron@netronome.com>
  */
+
+#include <asm/unaligned.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/slab.h>
@@ -285,15 +287,23 @@ nfp_rtsym_to_dest(struct nfp_cpp *cpp, const struct nfp_rtsym *sym,
 int __nfp_rtsym_read(struct nfp_cpp *cpp, const struct nfp_rtsym *sym,
                     u8 action, u8 token, u64 off, void *buf, size_t len)
 {
+       u64 sym_size = nfp_rtsym_size(sym);
        u32 cpp_id;
        u64 addr;
        int err;
 
+       if (off > sym_size) {
+               nfp_err(cpp, "rtsym '%s': read out of bounds: off: %lld + len: %zd > size: %lld\n",
+                       sym->name, off, len, sym_size);
+               return -ENXIO;
+       }
+       len = min_t(size_t, len, sym_size - off);
+
        if (sym->type == NFP_RTSYM_TYPE_ABS) {
-               __le64 tmp = cpu_to_le64(sym->addr);
+               u8 tmp[8];
 
-               len = min(len, sizeof(tmp));
-               memcpy(buf, &tmp, len);
+               put_unaligned_le64(sym->addr, tmp);
+               memcpy(buf, &tmp[off], len);
 
                return len;
        }
@@ -318,6 +328,12 @@ int __nfp_rtsym_readl(struct nfp_cpp *cpp, const struct nfp_rtsym *sym,
        u64 addr;
        int err;
 
+       if (off + 4 > nfp_rtsym_size(sym)) {
+               nfp_err(cpp, "rtsym '%s': readl out of bounds: off: %lld + 4 > size: %lld\n",
+                       sym->name, off, nfp_rtsym_size(sym));
+               return -ENXIO;
+       }
+
        err = nfp_rtsym_to_dest(cpp, sym, action, token, off, &cpp_id, &addr);
        if (err)
                return err;
@@ -338,6 +354,12 @@ int __nfp_rtsym_readq(struct nfp_cpp *cpp, const struct nfp_rtsym *sym,
        u64 addr;
        int err;
 
+       if (off + 8 > nfp_rtsym_size(sym)) {
+               nfp_err(cpp, "rtsym '%s': readq out of bounds: off: %lld + 8 > size: %lld\n",
+                       sym->name, off, nfp_rtsym_size(sym));
+               return -ENXIO;
+       }
+
        if (sym->type == NFP_RTSYM_TYPE_ABS) {
                *value = sym->addr;
                return 0;
@@ -359,10 +381,18 @@ int nfp_rtsym_readq(struct nfp_cpp *cpp, const struct nfp_rtsym *sym, u64 off,
 int __nfp_rtsym_write(struct nfp_cpp *cpp, const struct nfp_rtsym *sym,
                      u8 action, u8 token, u64 off, void *buf, size_t len)
 {
+       u64 sym_size = nfp_rtsym_size(sym);
        u32 cpp_id;
        u64 addr;
        int err;
 
+       if (off > sym_size) {
+               nfp_err(cpp, "rtsym '%s': write out of bounds: off: %lld + len: %zd > size: %lld\n",
+                       sym->name, off, len, sym_size);
+               return -ENXIO;
+       }
+       len = min_t(size_t, len, sym_size - off);
+
        err = nfp_rtsym_to_dest(cpp, sym, action, token, off, &cpp_id, &addr);
        if (err)
                return err;
@@ -383,6 +413,12 @@ int __nfp_rtsym_writel(struct nfp_cpp *cpp, const struct nfp_rtsym *sym,
        u64 addr;
        int err;
 
+       if (off + 4 > nfp_rtsym_size(sym)) {
+               nfp_err(cpp, "rtsym '%s': writel out of bounds: off: %lld + 4 > size: %lld\n",
+                       sym->name, off, nfp_rtsym_size(sym));
+               return -ENXIO;
+       }
+
        err = nfp_rtsym_to_dest(cpp, sym, action, token, off, &cpp_id, &addr);
        if (err)
                return err;
@@ -403,6 +439,12 @@ int __nfp_rtsym_writeq(struct nfp_cpp *cpp, const struct nfp_rtsym *sym,
        u64 addr;
        int err;
 
+       if (off + 8 > nfp_rtsym_size(sym)) {
+               nfp_err(cpp, "rtsym '%s': writeq out of bounds: off: %lld + 8 > size: %lld\n",
+                       sym->name, off, nfp_rtsym_size(sym));
+               return -ENXIO;
+       }
+
        err = nfp_rtsym_to_dest(cpp, sym, action, token, off, &cpp_id, &addr);
        if (err)
                return err;