[ Upstream commit 0c3e091319e4748cb36ac9a50848903dc6f54054 ]
This function contains multiple bugs after the following commits:
- ac551828993e ("modpost: i2c aliases need no trailing wildcard")
- 6543becf26ff ("mod/file2alias: make modalias generation safe for cross compiling")
Commit ac551828993e inserted the following code to do_eisa_entry():
else
strcat(alias, "*");
This is incorrect because 'alias' is uninitialized. If it is not
NULL-terminated, strcat() could cause a buffer overrun.
Even if 'alias' happens to be zero-filled, it would output:
MODULE_ALIAS("*");
This would match anything. As a result, the module could be loaded by
any unrelated uevent from an unrelated subsystem.
Commit ac551828993e introduced another bug.
Prior to that commit, the conditional check was:
if (eisa->sig[0])
This checked if the first character of eisa_device_id::sig was not '\0'.
However, commit ac551828993e changed it as follows:
if (sig[0])
sig[0] is NOT the first character of the eisa_device_id::sig. The
type of 'sig' is 'char (*)[8]', meaning that the type of 'sig[0]' is
'char [8]' instead of 'char'. 'sig[0]' and 'symval' refer to the same
address, which never becomes NULL.
The correct conversion would have been:
if ((*sig)[0])
However, this if-conditional was meaningless because the earlier change
in commit ac551828993e was incorrect.
This commit removes the entire incorrect code, which should never have
been executed.
Fixes: ac551828993e ("modpost: i2c aliases need no trailing wildcard")
Fixes: 6543becf26ff ("mod/file2alias: make modalias generation safe for cross compiling")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7f54e00e5842663c2cea501bbbdfa572c94348a3 ]
When MODULE_DEVICE_TABLE(tee, ) is built on a host with a different
endianness from the target architecture, it results in an incorrect
MODULE_ALIAS().
For example, see a case where drivers/char/hw_random/optee-rng.c
is built as a module for ARM little-endian.
If you build it on a little-endian host, you will get the correct
MODULE_ALIAS:
$ grep MODULE_ALIAS drivers/char/hw_random/optee-rng.mod.c
MODULE_ALIAS("tee:ab7a617c-b8e7-4d8f-8301-d09b61036b64*");
However, if you build it on a big-endian host, you will get a wrong
MODULE_ALIAS:
$ grep MODULE_ALIAS drivers/char/hw_random/optee-rng.mod.c
MODULE_ALIAS("tee:646b0361-9bd0-0183-8f4d-e7b87c617aab*");
The same problem also occurs when you enable CONFIG_CPU_BIG_ENDIAN,
and build it on a little-endian host.
This issue has been unnoticed because the ARM kernel is configured for
little-endian by default, and most likely built on a little-endian host
(cross-build on x86 or native-build on ARM).
The uuid field must not be reversed because uuid_t is an array of __u8.
Fixes: 0fc1db9d1059 ("tee: add bus driver framework for TEE based devices")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
