From: Greg Kroah-Hartman gregkh@linuxfoundation.org
From: Edwin Peer edwin.peer@broadcom.com
commit 20d7d1c5c9b11e9f538ed4a2289be106de970d3e upstream.
The following trace excerpt corresponds with a NULL pointer dereference of 'bp->irq_tbl' in bnxt_setup_inta() on an Aarch64 system after many device resets:
Unable to handle kernel NULL pointer dereference at ... 000000d ... pc : string+0x3c/0x80 lr : vsnprintf+0x294/0x7e0 sp : ffff00000f61ba70 pstate : 20000145 x29: ffff00000f61ba70 x28: 000000000000000d x27: ffff0000009c8b5a x26: ffff00000f61bb80 x25: ffff0000009c8b5a x24: 0000000000000012 x23: 00000000ffffffe0 x22: ffff000008990428 x21: ffff00000f61bb80 x20: 000000000000000d x19: 000000000000001f x18: 0000000000000000 x17: 0000000000000000 x16: ffff800b6d0fb400 x15: 0000000000000000 x14: ffff800b7fe31ae8 x13: 00001ed16472c920 x12: ffff000008c6b1c9 x11: ffff000008cf0580 x10: ffff00000f61bb80 x9 : 00000000ffffffd8 x8 : 000000000000000c x7 : ffff800b684b8000 x6 : 0000000000000000 x5 : 0000000000000065 x4 : 0000000000000001 x3 : ffff0a00ffffff04 x2 : 000000000000001f x1 : 0000000000000000 x0 : 000000000000000d Call trace: string+0x3c/0x80 vsnprintf+0x294/0x7e0 snprintf+0x44/0x50 __bnxt_open_nic+0x34c/0x928 [bnxt_en] bnxt_open+0xe8/0x238 [bnxt_en] __dev_open+0xbc/0x130 __dev_change_flags+0x12c/0x168 dev_change_flags+0x20/0x60 ...
Ordinarily, a call to bnxt_setup_inta() (not in trace due to inlining) would not be expected on a system supporting MSIX at all. However, if bnxt_init_int_mode() does not end up being called after the call to bnxt_clear_int_mode() in bnxt_fw_reset_close(), then the driver will think that only INTA is supported and bp->irq_tbl will be NULL, causing the above crash.
In the error recovery scenario, we call bnxt_clear_int_mode() in bnxt_fw_reset_close() early in the sequence. Ordinarily, we will call bnxt_init_int_mode() in bnxt_hwrm_if_change() after we reestablish communication with the firmware after reset. However, if the sequence has to abort before we call bnxt_init_int_mode() and if the user later attempts to re-open the device, then it will cause the crash above.
We fix it in 2 ways:
1. Check for bp->irq_tbl in bnxt_setup_int_mode(). If it is NULL, call bnxt_init_init_mode().
2. If we need to abort in bnxt_hwrm_if_change() and cannot complete the error recovery sequence, set the BNXT_STATE_ABORT_ERR flag. This will cause more drastic recovery at the next attempt to re-open the device, including a call to bnxt_init_int_mode().
Fixes: 3bc7d4a352ef ("bnxt_en: Add BNXT_STATE_IN_FW_RESET state.") Reviewed-by: Scott Branden scott.branden@broadcom.com Signed-off-by: Edwin Peer edwin.peer@broadcom.com Signed-off-by: Michael Chan michael.chan@broadcom.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -7925,10 +7925,18 @@ static void bnxt_setup_inta(struct bnxt bp->irq_tbl[0].handler = bnxt_inta; }
+static int bnxt_init_int_mode(struct bnxt *bp); + static int bnxt_setup_int_mode(struct bnxt *bp) { int rc;
+ if (!bp->irq_tbl) { + rc = bnxt_init_int_mode(bp); + if (rc || !bp->irq_tbl) + return rc ?: -ENODEV; + } + if (bp->flags & BNXT_FLAG_USING_MSIX) bnxt_setup_msix(bp); else @@ -8113,7 +8121,7 @@ static int bnxt_init_inta(struct bnxt *b
static int bnxt_init_int_mode(struct bnxt *bp) { - int rc = 0; + int rc = -ENODEV;
if (bp->flags & BNXT_FLAG_MSIX_CAP) rc = bnxt_init_msix(bp); @@ -8748,7 +8756,8 @@ static int bnxt_hwrm_if_change(struct bn { struct hwrm_func_drv_if_change_output *resp = bp->hwrm_cmd_resp_addr; struct hwrm_func_drv_if_change_input req = {0}; - bool resc_reinit = false, fw_reset = false; + bool fw_reset = !bp->irq_tbl; + bool resc_reinit = false; u32 flags = 0; int rc;
@@ -8776,6 +8785,7 @@ static int bnxt_hwrm_if_change(struct bn
if (test_bit(BNXT_STATE_IN_FW_RESET, &bp->state) && !fw_reset) { netdev_err(bp->dev, "RESET_DONE not set during FW reset.\n"); + set_bit(BNXT_STATE_ABORT_ERR, &bp->state); return -ENODEV; } if (resc_reinit || fw_reset) {