From: Alok Tiwari alok.a.tiwari@oracle.com
[ Upstream commit edb888d29748cee674006a52e544925dacc7728e ]
Logic here always sets hdr->version to 2 if it is not a BE3 or Lancer chip, even if it is BE2. Use 'else if' to prevent multiple assignments, setting version 0 for BE2, version 1 for BE3 and Lancer, and version 2 for others. Fixes potential incorrect version setting when BE2_chip and BE3_chip/lancer_chip checks could both be true.
Signed-off-by: Alok Tiwari alok.a.tiwari@oracle.com Link: https://patch.msgid.link/20250519141731.691136-1-alok.a.tiwari@oracle.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org ---
Based on my analysis, let me provide my determination: **YES** This commit should be backported to stable kernel trees. ## Detailed Analysis: ### 1. **Nature of the Bug:** The commit fixes a logical error in command version selection for the `be_cmd_get_stats()` function in the Emulex be2net driver. The original code had this problematic logic: ```c if (BE2_chip(adapter)) hdr->version = 0; if (BE3_chip(adapter) || lancer_chip(adapter)) // <- Missing "else" hdr->version = 1; else hdr->version = 2; ``` The bug is that the second `if` should be `else if`. Without the `else if`, if a chip satisfies both `BE2_chip(adapter)` AND `(BE3_chip(adapter) || lancer_chip(adapter))` conditions, the version would be incorrectly set multiple times, with the final value being either 1 or 2 depending on subsequent conditions. ### 2. **Impact Assessment:** - **User-facing impact:** This bug could cause incorrect command versions to be sent to the hardware, potentially leading to statistics retrieval failures or unexpected behavior - **Scope:** Affects all users of Emulex be2net network adapters where the chip detection logic could overlap - **Severity:** While not a critical security issue, it affects driver functionality and could lead to network statistics reporting failures ### 3. **Code Change Analysis:** The fix is minimal and surgical: - **Single line change:** Only changes `if` to `else if` on line 1612 - **No functional additions:** Does not introduce new features or change APIs - **Low regression risk:** The change makes the logic more explicit and prevents multiple assignments - **Clear intent:** The fix aligns with the comment stating "version 1 of the cmd is not supported only by BE2" ### 4. **Backport Suitability Criteria:** ✅ **Fixes important bug:** Corrects incorrect hardware command version selection ✅ **Small and contained:** Single line change with no side effects ✅ **Low regression risk:** Makes existing logic more explicit and correct ✅ **No architectural changes:** Pure bug fix without design modifications ✅ **Subsystem confined:** Only affects be2net driver statistics functionality ### 5. **Comparison with Historical Commits:** The provided historical commits were all marked "NO" for backporting because they were: - Version string updates (cosmetic changes) - Code simplifications (non-critical improvements) - Driver version removals (cleanup) In contrast, this commit fixes actual functional logic that could cause incorrect behavior. ### 6. **Stable Tree Compliance:** This commit perfectly fits the stable tree criteria: - Fixes a clear bug in existing code - Has minimal risk of introducing regressions - Affects a specific driver subsystem - Does not change user-visible APIs or behavior (except fixing incorrect behavior) The commit message clearly explains the problem and solution, and the change is straightforward to verify and test.
drivers/net/ethernet/emulex/benet/be_cmds.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/emulex/benet/be_cmds.c b/drivers/net/ethernet/emulex/benet/be_cmds.c index 88f69c486ed09..1cdb7ca019f57 100644 --- a/drivers/net/ethernet/emulex/benet/be_cmds.c +++ b/drivers/net/ethernet/emulex/benet/be_cmds.c @@ -1608,7 +1608,7 @@ int be_cmd_get_stats(struct be_adapter *adapter, struct be_dma_mem *nonemb_cmd) /* version 1 of the cmd is not supported only by BE2 */ if (BE2_chip(adapter)) hdr->version = 0; - if (BE3_chip(adapter) || lancer_chip(adapter)) + else if (BE3_chip(adapter) || lancer_chip(adapter)) hdr->version = 1; else hdr->version = 2;