diff options
| author | Philippe Mathieu-Daudé <f4bug@amsat.org> | 2021-08-03 01:55:24 +0200 |
|---|---|---|
| committer | Philippe Mathieu-Daudé <f4bug@amsat.org> | 2021-08-03 19:34:51 +0200 |
| commit | 4ac0b72bae85cf94ae0e5153b9c2c288c71667d4 (patch) | |
| tree | 5e5d66138991d2e475f48c9114bdf3f9e2d8d962 /hw/sd | |
| parent | 2a0396285daa9483459ec1d3791951300b595e85 (diff) | |
hw/sd/sdcard: Fix assertion accessing out-of-range addresses with CMD30
OSS-Fuzz found sending illegal addresses when querying the write
protection bits triggers the assertion added in commit 84816fb63e5
("hw/sd/sdcard: Assert if accessing an illegal group"):
qemu-fuzz-i386-target-generic-fuzz-sdhci-v3: ../hw/sd/sd.c:824: uint32_t sd_wpbits(SDState *, uint64_t):
Assertion `wpnum < sd->wpgrps_size' failed.
#3 0x7f62a8b22c91 in __assert_fail
#4 0x5569adcec405 in sd_wpbits hw/sd/sd.c:824:9
#5 0x5569adce5f6d in sd_normal_command hw/sd/sd.c:1389:38
#6 0x5569adce3870 in sd_do_command hw/sd/sd.c:1737:17
#7 0x5569adcf1566 in sdbus_do_command hw/sd/core.c:100:16
#8 0x5569adcfc192 in sdhci_send_command hw/sd/sdhci.c:337:12
#9 0x5569adcfa3a3 in sdhci_write hw/sd/sdhci.c:1186:9
#10 0x5569adfb3447 in memory_region_write_accessor softmmu/memory.c:492:5
It is legal for the CMD30 to query for out-of-range addresses.
Such invalid addresses are simply ignored in the response (write
protection bits set to 0).
In commit 84816fb63e5 ("hw/sd/sdcard: Assert if accessing an illegal
group") we misplaced the assertion *before* we test the address is
in range. Move it *after*.
Include the qtest reproducer provided by Alexander Bulekov:
$ make check-qtest-i386
...
Running test qtest-i386/fuzz-sdcard-test
qemu-system-i386: ../hw/sd/sd.c:824: sd_wpbits: Assertion `wpnum < sd->wpgrps_size' failed.
Cc: qemu-stable@nongnu.org
Reported-by: OSS-Fuzz (Issue 29225)
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Fixes: 84816fb63e5 ("hw/sd/sdcard: Assert if accessing an illegal group")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/495
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210802235524.3417739-3-f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Diffstat (limited to 'hw/sd')
| -rw-r--r-- | hw/sd/sd.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/hw/sd/sd.c b/hw/sd/sd.c index 707dcc12a1..bb5dbff68c 100644 --- a/hw/sd/sd.c +++ b/hw/sd/sd.c @@ -821,7 +821,6 @@ static uint32_t sd_wpbits(SDState *sd, uint64_t addr) wpnum = sd_addr_to_wpnum(addr); for (i = 0; i < 32; i++, wpnum++, addr += WPGROUP_SIZE) { - assert(wpnum < sd->wpgrps_size); if (addr >= sd->size) { /* * If the addresses of the last groups are outside the valid range, @@ -829,6 +828,7 @@ static uint32_t sd_wpbits(SDState *sd, uint64_t addr) */ continue; } + assert(wpnum < sd->wpgrps_size); if (test_bit(wpnum, sd->wp_groups)) { ret |= (1 << i); } |