Matt Vollrath fa5ba9867a e1000/e1000e: Fix leak in DMA error cleanup ...

[ Upstream commit e94eaef111 ]

If an error is encountered while mapping TX buffers, the driver should
unmap any buffers already mapped for that skb.

Because count is incremented after a successful mapping, it will always
match the correct number of unmappings needed when dma_error is reached.
Decrementing count before the while loop in dma_error causes an
off-by-one error. If any mapping was successful before an unsuccessful
mapping, exactly one DMA mapping would leak.

In these commits, a faulty while condition caused an infinite loop in
dma_error:
Commit 03b1320dfc ("e1000e: remove use of skb_dma_map from e1000e
driver")
Commit 602c0554d7 ("e1000: remove use of skb_dma_map from e1000 driver")

Commit c1fa347f20 ("e1000/e1000e/igb/igbvf/ixgb/ixgbe: Fix tests of
unsigned in *_tx_map()") fixed the infinite loop, but introduced the
off-by-one error.

This issue may still exist in the igbvf driver, but I did not address it
in this patch.

Fixes: c1fa347f20 ("e1000/e1000e/igb/igbvf/ixgb/ixgbe: Fix tests of unsigned in *_tx_map()")
Assisted-by: Claude:claude-4.6-opus
Signed-off-by: Matt Vollrath <tactii@gmail.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

2026-03-25 11:08:29 +01:00

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e1000_ethtool.c

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e1000_hw.c

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e1000_hw.h

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e1000_main.c

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e1000_osdep.h

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e1000_param.c

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e1000.h

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Makefile

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