On 3/11/21 9:18 AM, Lukasz Majewski wrote:
Hi Heinrich,
Hello Lukasz,
Jose and I have observed segmentation violations when
dfu_free_entities() is called.
Thanks for finding them.
In our scenario we have:
dfu_alt_info=
sf 0:0=u-boot-bin raw 0x100000 0x50000;u-boot-env raw 0x150000
0x200000
dfu_free_entities() is called with these entries in dfu:
u-boot-env:
dfu->data.sf.dev 0000000015baf420 m25p16
dfu->data.sf.dev->dev 0000000015888410 spi.bin@0
u-boot-bin:
dfu->data.sf.dev 0000000015baf420 m25p16
dfu->data.sf.dev->dev 0000000015888410 spi.bin@0
The same device is released twice which eventually leads to the
segmentation fault in device_chld_remove().
If I remember correctly that was fixed some time ago... Maybe something
has changed with recent patches.
Was it working before? Or is the above scenario a new one?
Jose and Takahiro have provided patches that exercise DFU by repeatedly
calling dfu_init_env_entities() and dfu_free_entities(). See function
efi_get_dfu_info().
Furthermore for testing we use a dfu_alt_info with multiple images on
the same device.
No change was done in this part of DFU since 2014. So this is a
longstanding problem that we now uncovered.
[PATCH 1/1] mtd: spi_flash_free()
https://lists.denx.de/pipermail/u-boot/2021-March/443915.html
fixes the issue for the case of DM_SPI_FLASH.
But we should also address the DFU system itself.
Best regards
Heinrich
Program received signal SIGSEGV, Segmentation fault.
device_chld_remove (
dev=dev@entry=0x5555557f6750 <av_+1936>, drv=drv@entry=0x0,
flags=flags@entry=1)
at drivers/core/device-remove.c:55
55 list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
We must ensure that dfu_free_entities() removes each device only once.
Another bug in dfu_free_entities() is that only the first list member
is freed. free() should be called for all list members.
Yes. Correct.
Best regards
Heinrich
Best regards,
Lukasz Majewski
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