diff options
| author | AKASHI Takahiro | 2021-01-22 10:42:48 +0900 |
|---|---|---|
| committer | Heinrich Schuchardt | 2021-01-23 07:56:53 +0100 |
| commit | 30f8222bb0016eef29afdd997bd1b3cdc486fdf9 (patch) | |
| tree | d1c0e1fab126f3b6598853ed14ecae9cd9cd4ce7 /cmd/efidebug.c | |
| parent | 6e8c28cf523257acba5d6ccb4328253595640931 (diff) | |
cmd: efidebug: always check return code from get_variable()
CID 316364 says:
> Null pointer dereferences (FORWARD_NULL)
> printf("Result total size: 0x%x\n", result->variable_total_size);
at do_efi_capsule_res().
The code is basically safe because a buffer for "result" is allocated
by malloc() and filled up by the second get_variable(), which fails any way
if the allocation has failed.
But the first (and second) get_variable() possibly returns an error other
than EFI_SUCCESS. We always need to check the return code from
get_variable() before accessing the data in "result".
While this change won't suppress CID 316364, the resulting code is much
safer.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Diffstat (limited to 'cmd/efidebug.c')
| -rw-r--r-- | cmd/efidebug.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/cmd/efidebug.c b/cmd/efidebug.c index 9a2d4ddd5ef..83bc2196a5a 100644 --- a/cmd/efidebug.c +++ b/cmd/efidebug.c @@ -189,14 +189,16 @@ static int do_efi_capsule_res(struct cmd_tbl *cmdtp, int flag, ret = EFI_CALL(RT->get_variable(var_name16, &guid, NULL, &size, NULL)); if (ret == EFI_BUFFER_TOO_SMALL) { result = malloc(size); + if (!result) + return CMD_RET_FAILURE; ret = EFI_CALL(RT->get_variable(var_name16, &guid, NULL, &size, result)); - if (ret != EFI_SUCCESS) { - free(result); - printf("Failed to get %ls\n", var_name16); + } + if (ret != EFI_SUCCESS) { + free(result); + printf("Failed to get %ls\n", var_name16); - return CMD_RET_FAILURE; - } + return CMD_RET_FAILURE; } printf("Result total size: 0x%x\n", result->variable_total_size); |